SSM框架下载文件到数据库

有人知道如何使用 SSM框架,上传文件时不是上传到服务器,而是转换成数据流的格式存入数据库,数据库存储的类型是Blob,当下载时从数据库取出来再进行下载。

有大神有完整的解说和代码?求教。。。。。

1个回答

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SSM框架Tomcat跑一段时间后抛异常
用的是Spring + SpringMVC+ Mybatis 项目部署后跑一段时间后会跑异常 但是可以正常访问 下面是抛出的异常: 2017-08-10 03:20:46 [Prototyper] ERROR org.logicalcobwebs.proxool.lvseu - Prototype com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to database server. Attempted reconnect 3 times. Giving up. at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) at java.lang.reflect.Constructor.newInstance(Constructor.java:526) at com.mysql.jdbc.Util.handleNewInstance(Util.java:406) at com.mysql.jdbc.Util.getInstance(Util.java:381) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:984) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:956) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:926) at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2270) at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:723) at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:46) at sun.reflect.GeneratedConstructorAccessor57.newInstance(Unknown Source) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) at java.lang.reflect.Constructor.newInstance(Constructor.java:526) at com.mysql.jdbc.Util.handleNewInstance(Util.java:406) at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:302) at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:282) at java.sql.DriverManager.getConnection(DriverManager.java:571) at java.sql.DriverManager.getConnection(DriverManager.java:187) at org.logicalcobwebs.proxool.DefaultConnectionBuilder.buildConnection(DefaultConnectionBuilder.java:39) at org.logicalcobwebs.proxool.Prototyper.buildConnection(Prototyper.java:159) at org.logicalcobwebs.proxool.Prototyper.sweep(Prototyper.java:102) at org.logicalcobwebs.proxool.PrototyperThread.run(PrototyperThread.java:44) Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure Last packet sent to the server was 0 ms ago. at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) at java.lang.reflect.Constructor.newInstance(Constructor.java:526) at com.mysql.jdbc.Util.handleNewInstance(Util.java:406) at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1074) at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:335) at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2194) ... 14 more Caused by: java.net.ConnectException: Connection timed out: connect at java.net.DualStackPlainSocketImpl.connect0(Native Method) at java.net.DualStackPlainSocketImpl.socketConnect(DualStackPlainSocketImpl.java:79) at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:339) at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:200) at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:182) at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:172) at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392) at java.net.Socket.connect(Socket.java:579) at java.net.Socket.connect(Socket.java:528) at java.net.Socket.<init>(Socket.java:425) at java.net.Socket.<init>(Socket.java:241) at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:253) at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:284) ... 15 more 我的配置文件 proxool.prototypeCount=5 proxool.maximumActiveTime=300000 proxool.maximumConnectionLifetime=18000000 proxool.minimumConnectionCount=5 proxool.maximumConnectionCount=40 proxool.alias=lvseu proxool.simultaneous-build-throttle=20 proxool.prototype-count=2 proxool.houseKeepingTestSql=select CURRENT_DATE proxool.hourseKeepingSleepTime=30000 <property name="driver" value="${connection.driver_class}" /> <property name="driverUrl" value="${connection.url}" /> <property name="user" value="${connection.username}" /> <property name="password" value="${connection.password}" /> <!-- 测试的SQL执行语句 --> <property name="houseKeepingTestSql" value="${proxool.houseKeepingTestSql}"/> <!-- 最少保持的空闲连接数 (默认2个) --> <property name="prototypeCount" value="${proxool.prototypeCount}" /> <!-- 最大活动时间(超过此时间线程将被kill,默认为5分钟) --> <property name="maximumActiveTime" value="${proxool.maximumActiveTime}" /> <!-- 最小连接数 (默认2个) --> <property name="minimumConnectionCount" value="${proxool.minimumConnectionCount}" /> <!-- 最大连接数 (默认10个) --> <property name="maximumConnectionCount" value="${proxool.maximumConnectionCount}" /> <!-- 连接最长时间(默认为4个小时) --> <property name="maximumConnectionLifetime" value="${proxool.maximumConnectionLifetime}" /> <!-- 数据库别名 --> <property name="alias" value="${proxool.alias}" /> <!-- proxool自动侦察各个连接状态的时间间隔(毫秒),侦察到空闲的连接就马上回收,超时的销毁 默认30秒) --> <property name="houseKeepingSleepTime" value="${proxool.hourseKeepingSleepTime}" /> 求大神给看一下 自己找了很久 曾百度说是数据库8个小时断开连接 按这个结果也试了 还是报
数据库配置文件的问题
ssm框架下数据库配置文件jdbc.properties,其中做修改后使用无变动,删除文件后,依然能够使用,求大神告知原因
xmemcached和整合SSM框架 单元测试没问提 项目启动后造成mybatis连接不到数据库?
路径是没问提的 本来一切正常 我在原来的基础上整合了memcached。 memcached测试链接对数据进行操作没问题 但是项目运行起来以后 mybatis无法链接数据库; 注释掉memcached配置 就会回复正常 ## memcached.xml <!-- properties config --> <bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer"> <property name="order" value="1" /> <property name="ignoreUnresolvablePlaceholders" value="true" /> <property name="locations"> <list> <value>classpath:config/memcached.properties</value> </list> </property> </bean> <!-- Memcached配置 --> <!-- p:connectionPoolSize="${memcached.connectionPoolSize}" p:failureMode="${memcached.failureMode}" --> <bean id="memcachedClientBuilder" class="net.rubyeye.xmemcached.XMemcachedClientBuilder"> <constructor-arg> <list> <bean class="java.net.InetSocketAddress"> <constructor-arg> <value>${memcached.server1.host}</value> </constructor-arg> <constructor-arg> <value>${memcached.server1.port}</value> </constructor-arg> </bean> </list> </constructor-arg> <constructor-arg> <list> <value>${memcached.server1.weight}</value> </list> </constructor-arg> <property name="commandFactory"> <bean class="net.rubyeye.xmemcached.command.TextCommandFactory" /> </property> <property name="sessionLocator"> <bean class="net.rubyeye.xmemcached.impl.KetamaMemcachedSessionLocator" /> </property> <property name="transcoder"> <bean class="net.rubyeye.xmemcached.transcoders.SerializingTranscoder" /> </property> <property name="connectionPoolSize" value="${memcached.connectionPoolSize}" /> <property name="failureMode" value="${memcached.failureMode}" /> </bean> <!-- Use factory bean to build memcached client --> <bean id="memcachedClient" factory-bean="memcachedClientBuilder" factory-method="build" destroy-method="shutdown" /> ## mybatis <!-- 引入配置文件 --> <bean id="propertyConfigurer" class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer"> <property name="location" value="classpath:config/jdbc.properties" /> </bean> <bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close"> <property name="driverClassName" value="${driver}" /> <property name="url" value="${url}" /> <property name="username" value="${username}" /> <property name="password" value="${password}" /> <!-- 初始化连接大小 --> <property name="initialSize" value="${initialSize}"></property> <!-- 连接池最大数量 --> <property name="maxActive" value="${maxActive}"></property> <!-- 连接池最大空闲 --> <property name="maxIdle" value="${maxIdle}"></property> <!-- 连接池最小空闲 --> <property name="minIdle" value="${minIdle}"></property> <!-- 获取连接最大等待时间 --> <property name="maxWait" value="${maxWait}"></property> </bean> <!--spring与mybatis整合 --> <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean"> <property name="dataSource" ref="dataSource" /> <!-- 自动扫描mapping.xml文件 --> <property name="mapperLocations" value="classpath:mapping/**/*.xml"> </property> <!-- 全局配置 --> <!-- 若不保留mybatis配置文件用上面那条替换这一条 --> <!-- <property name="configLocation" value="classpath:mybatis/sqlMapConfig.xml"/> --> <!-- mybatis配置文件路径 --> <property name="configLocation" value="classpath:/config/spring/mybatis.xml" /> </bean> <!-- DAO接口所在包名,Spring会自动查找其下的类 --> <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer"> <!-- 扫描包路径,需要扫描多个包中间用逗号隔开 --> <property name="basePackage" value="com.ysjian.bud.app.dao,com.ysjian.bud.backstage.dao" /> <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"></property> </bean> ## 运行错误信息 org.mybatis.spring.MyBatisSystemException: nested exception is org.apache.ibatis.exceptions.PersistenceException: Error updating database. Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is org.apache.commons.dbcp.SQLNestedException: Cannot create PoolableConnectionFactory (Could not create connection to database server. Attempted reconnect 3 times. Giving up.) Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is org.apache.commons.dbcp.SQLNestedException: Cannot create PoolableConnectionFactory (Could not create connection to database server. Attempted reconnect 3 times. Giving up.) at org.mybatis.spring.MyBatisExceptionTranslator.translateExceptionIfPossible(MyBatisExceptionTranslator.java:75) at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:371) at com.sun.proxy.$Proxy16.delete(Unknown Source) at org.mybatis.spring.SqlSessionTemplate.delete(SqlSessionTemplate.java:268) at org.apache.ibatis.binding.MapperMethod.execute(MapperMethod.java:57) at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:52) at com.sun.proxy.$Proxy34.deleteSayHi(Unknown Source) at appLoginTest.BUDTest.Test1(BUDTest.java:46) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) at java.lang.reflect.Method.invoke(Unknown Source) at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:47) at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12) at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:44) at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17) at org.springframework.test.context.junit4.statements.RunBeforeTestMethodCallbacks.evaluate(RunBeforeTestMethodCallbacks.java:74) at org.springframework.test.context.junit4.statements.RunAfterTestMethodCallbacks.evaluate(RunAfterTestMethodCallbacks.java:83) at org.springframework.test.context.junit4.statements.SpringRepeat.evaluate(SpringRepeat.java:72) at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:232) at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:89) at org.junit.runners.ParentRunner$3.run(ParentRunner.java:238) at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:63) at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:236) at org.junit.runners.ParentRunner.access$000(ParentRunner.java:53) at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:229) at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61) at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:71) at org.junit.runners.ParentRunner.run(ParentRunner.java:309) at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:175) at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:86) at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:539) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:761) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:461) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:207) Caused by: org.apache.ibatis.exceptions.PersistenceException: ### Error updating database. Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is org.apache.commons.dbcp.SQLNestedException: Cannot create PoolableConnectionFactory (Could not create connection to database server. Attempted reconnect 3 times. Giving up.) Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is org.apache.commons.dbcp.SQLNestedException: Cannot create PoolableConnectionFactory (Could not create connection to database server. Attempted reconnect 3 times. Giving up.) at org.apache.ibatis.exceptions.ExceptionFactory.wrapException(ExceptionFactory.java:26) at org.apache.ibatis.session.defaults.DefaultSqlSession.update(DefaultSqlSession.java:154) at org.apache.ibatis.session.defaults.DefaultSqlSession.delete(DefaultSqlSession.java:165) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) at java.lang.reflect.Method.invoke(Unknown Source) at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:358) ... 34 more Caused by: org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is org.apache.commons.dbcp.SQLNestedException: Cannot create PoolableConnectionFactory (Could not create connection to database server. Attempted reconnect 3 times. Giving up.) at org.springframework.jdbc.datasource.DataSourceUtils.getConnection(DataSourceUtils.java:80) at org.mybatis.spring.transaction.SpringManagedTransaction.openConnection(SpringManagedTransaction.java:81) at org.mybatis.spring.transaction.SpringManagedTransaction.getConnection(SpringManagedTransaction.java:67) at org.apache.ibatis.executor.BaseExecutor.getConnection(BaseExecutor.java:279) at org.apache.ibatis.executor.SimpleExecutor.prepareStatement(SimpleExecutor.java:72) at org.apache.ibatis.executor.SimpleExecutor.doUpdate(SimpleExecutor.java:47) at org.apache.ibatis.executor.BaseExecutor.update(BaseExecutor.java:105) at org.apache.ibatis.executor.CachingExecutor.update(CachingExecutor.java:71) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) at java.lang.reflect.Method.invoke(Unknown Source) at org.apache.ibatis.plugin.Plugin.invoke(Plugin.java:62) at com.sun.proxy.$Proxy54.update(Unknown Source) at org.apache.ibatis.session.defaults.DefaultSqlSession.update(DefaultSqlSession.java:152) ... 40 more Caused by: org.apache.commons.dbcp.SQLNestedException: Cannot create PoolableConnectionFactory (Could not create connection to database server. Attempted reconnect 3 times. Giving up.) at org.apache.commons.dbcp.BasicDataSource.createDataSource(BasicDataSource.java:1225) at org.apache.commons.dbcp.BasicDataSource.getConnection(BasicDataSource.java:880) at org.springframework.jdbc.datasource.DataSourceUtils.doGetConnection(DataSourceUtils.java:111) at org.springframework.jdbc.datasource.DataSourceUtils.getConnection(DataSourceUtils.java:77) ... 54 more Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to database server. Attempted reconnect 3 times. Giving up. at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source) at java.lang.reflect.Constructor.newInstance(Unknown Source) at com.mysql.jdbc.Util.handleNewInstance(Util.java:409) at com.mysql.jdbc.Util.getInstance(Util.java:384) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1013) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:987) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:973) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:918) at com.mysql.jdbc.ConnectionImpl.connectWithRetries(ConnectionImpl.java:2405) at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2326) at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:832) at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:46) at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source) at java.lang.reflect.Constructor.newInstance(Unknown Source) at com.mysql.jdbc.Util.handleNewInstance(Util.java:409) at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:417) at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:344) at org.apache.commons.dbcp.DriverConnectionFactory.createConnection(DriverConnectionFactory.java:38) at org.apache.commons.dbcp.PoolableConnectionFactory.makeObject(PoolableConnectionFactory.java:294) at org.apache.commons.dbcp.BasicDataSource.validateConnectionFactory(BasicDataSource.java:1247) at org.apache.commons.dbcp.BasicDataSource.createDataSource(BasicDataSource.java:1221) ... 57 more Caused by: java.sql.SQLException: Access denied for user 'DELL'@'localhost' (using password: YES) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1084) at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4232) at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4164) at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:926) at com.mysql.jdbc.MysqlIO.proceedHandshakeWithPluggableAuthentication(MysqlIO.java:1748) at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1288) at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2506) at com.mysql.jdbc.ConnectionImpl.connectWithRetries(ConnectionImpl.java:2344) ... 71 more
ssm框架demo遇到的问题
各位老哥们大家好,我是一名大二学生,自学Java一年半了,进步很慢,在ssm框架上遇到了问题,认识的人少,这个问题没人指点我,我很难再往后学习。 下面描述一下我遇到的问题吧:我比较抵触写jsp,所以从javaweb开始就尝试前后端分离,在学习ssm框架时,讲师用的都是jsp,我以为只要把springmvc的视图解析器中suffix配置成.html就行了,事情却没那么简单,项目一运行就报404,按理应该默认去找index.html,但是却直接报错,希望老哥们给我分析一下我哪里有错误。希望前辈能指导一下,谢谢了 ## 1:创建项目,我用的是IDEA,创建时选择的是Maven的webapp骨架。 ## 2:导入pom依赖 ``` <?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd"> <modelVersion>4.0.0</modelVersion> <packaging>war</packaging> <name>register</name> <groupId>xyz.peterparker</groupId> <artifactId>register</artifactId> <version>1.0-SNAPSHOT</version> <build> <plugins> <plugin> <groupId>org.mortbay.jetty</groupId> <artifactId>maven-jetty-plugin</artifactId> <version>6.1.7</version> <configuration> <connectors> <connector implementation="org.mortbay.jetty.nio.SelectChannelConnector"> <port>8888</port> <maxIdleTime>30000</maxIdleTime> </connector> </connectors> <webAppSourceDirectory>${project.build.directory}/${pom.artifactId}-${pom.version} </webAppSourceDirectory> <contextPath>/</contextPath> </configuration> </plugin> </plugins> </build> <properties> <spring.version>5.2.1.RELEASE</spring.version> <slf4j.version>1.6.6</slf4j.version> <log4j.version>1.2.12</log4j.version> <mybatis.version>3.4.5</mybatis.version> </properties> <dependencies> <!--dependency> <groupId>xyz.peterparker</groupId> <artifactId>[the artifact id of the block to be mounted]</artifactId> <version>1.0-SNAPSHOT</version> </dependency--> <dependency> <groupId>org.aspectj</groupId> <artifactId>aspectjweaver</artifactId> <version>1.6.8</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-aop</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-context</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-context-support</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-web</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-orm</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-beans</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-core</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-webmvc</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-tx</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>junit</groupId> <artifactId>junit</artifactId> <version>4.12</version> <scope>test</scope> </dependency> <dependency> <groupId>javax.servlet</groupId> <artifactId>javax.servlet-api</artifactId> <version>3.1.0</version> <scope>provided</scope> </dependency> <dependency> <groupId>javax.servlet.jsp</groupId> <artifactId>jsp-api</artifactId> <version>2.0</version> <scope>provided</scope> </dependency> <dependency> <groupId>jstl</groupId> <artifactId>jstl</artifactId> <version>1.2</version> </dependency> <!-- log start --> <dependency> <groupId>log4j</groupId> <artifactId>log4j</artifactId> <version>${log4j.version}</version> </dependency> <dependency> <groupId>org.slf4j</groupId> <artifactId>slf4j-api</artifactId> <version>${slf4j.version}</version> </dependency> <dependency> <groupId>org.slf4j</groupId> <artifactId>slf4j-log4j12</artifactId> <version>${slf4j.version}</version> </dependency> <!-- log end --> <dependency> <groupId>org.mybatis</groupId> <artifactId>mybatis-spring</artifactId> <version>1.3.0</version> </dependency> <dependency> <groupId>org.mybatis</groupId> <artifactId>mybatis</artifactId> <version>${mybatis.version}</version> </dependency> <dependency> <groupId>c3p0</groupId> <artifactId>c3p0</artifactId> <version>0.9.1.2</version> <type>jar</type> <scope>compile</scope> </dependency> <dependency> <groupId>javax.annotation</groupId> <artifactId>jsr250-api</artifactId> <version>1.0</version> </dependency> <!-- https://mvnrepository.com/artifact/mysql/mysql-connector-java --> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>8.0.16</version> </dependency> </dependencies> </project> ``` ## 3:创建包结构 ![图片说明](https://img-ask.csdn.net/upload/202002/19/1582083667_469404.png) ## 4:编写web.xml ``` <?xml version="1.0" encoding="UTF-8"?> <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd" version="3.1"> <!-- 更改applicationContext的默认位置 --> <context-param> <param-name>contextConfigLocation</param-name> <param-value>classpath:applicationContext.xml</param-value> </context-param> <!-- 配置监听器 --> <listener> <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class> </listener> <listener> <listener-class>org.springframework.web.context.request.RequestContextListener</listener-class> </listener> <!-- 配置前端控制器 --> <servlet> <servlet-name>dispatcherServlet</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <init-param> <param-name>contextConfigLocation</param-name> <param-value>classpath:springmvc.xml</param-value> </init-param> <load-on-startup>1</load-on-startup> </servlet> <servlet-mapping> <servlet-name>dispatcherServlet</servlet-name> <url-pattern>/*</url-pattern> </servlet-mapping> <!-- 配置解决中文乱码的过滤器 --> <filter> <filter-name>characterEncodingFilter</filter-name> <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class> <init-param> <param-name>encoding</param-name> <param-value>UTF-8</param-value> </init-param> </filter> <filter-mapping> <filter-name>characterEncodingFilter</filter-name> <url-pattern>/*</url-pattern> </filter-mapping> <welcome-file-list> <welcome-file>index.html</welcome-file> <welcome-file>index.htm</welcome-file> <welcome-file>index.jsp</welcome-file> <welcome-file>default.html</welcome-file> <welcome-file>default.htm</welcome-file> <welcome-file>default.jsp</welcome-file> </welcome-file-list> </web-app> ``` ## 5:编写applicationContext.xml ``` <?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context" xmlns:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd"> <!-- 扫描service和dao --> <context:component-scan base-package="dao" /> <context:component-scan base-package="service" /> <!-- 引入dataSource.properties --> <context:property-placeholder location="classpath:dataSource.properties" /> <!-- 配置数据库连接池 --> <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource"> <property name="driverClass" value="${driverClass}" /> <property name="jdbcUrl" value="${jdbcUrl}" /> <property name="user" value="${user}" /> <property name="password" value="${password}" /> </bean> <!-- 配置SqlSessionFactoryBean --> <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean"> <property name="dataSource" ref="dataSource" /> </bean> <!-- 配置扫描dao --> <bean id="mapperScannerConfigurer" class="org.mybatis.spring.mapper.MapperScannerConfigurer"> <property name="basePackage" value="dao" /> </bean> <!-- 配置声明式事务管理 --> <bean id="dataSourceTransactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager"> <property name="dataSource" ref="dataSource" /> </bean> <tx:annotation-driven transaction-manager="dataSourceTransactionManager" /> </beans> ``` ## 6:编写dataSource.properties ``` driverClass=com.mysql.cj.jdbc.Driver jdbcUrl=jdbc:mysql://localhost/user?useSSL=false&serverTimezone=Asia/Shanghai user=root password=rhw19990625 ``` ## 7:编写springmvc.xml ``` <?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:context="http://www.springframework.org/schema/context" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:aop="http://www.springframework.org/schema/aop" xsi:schemaLocation=" http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd"> <!-- 配置扫描controller --> <context:component-scan base-package="controller" /> <!-- 配置视图解析器 --> <bean id="internalResourceViewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver"> <property name="prefix" value="pages" /> <property name="suffix" value=".html" /> <property name="contentType" value="text/html" /> </bean> <mvc:annotation-driven /> <mvc:default-servlet-handler /> <aop:aspectj-autoproxy proxy-target-class="true"/> </beans> ``` ## 8:编写User实体类 ``` package domain; import java.io.Serializable; public class User implements Serializable { private String username; private Integer tel; private String password; public User() { } public User(String username, Integer tel, String password) { this.username = username; this.tel = tel; this.password = password; } public String getUsername() { return username; } public void setUsername(String username) { this.username = username; } public Integer getTel() { return tel; } public void setTel(Integer tel) { this.tel = tel; } public String getPassword() { return password; } public void setPassword(String password) { this.password = password; } } ``` ## 9:编写dao层接口UserDao ``` package dao; import domain.User; import org.apache.ibatis.annotations.Insert; import org.springframework.stereotype.Repository; @Repository public interface UserDao { @Insert("insert into user values(#{username},#{tel},#{password})") void insert(User user); } ``` ## 10:编写service层接口UserService ``` package service; import domain.User; public interface UserService { void insert(User user); } ``` ## 11:编写service层实现类UserServiceImpl ``` package service.impl; import dao.UserDao; import domain.User; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Service; import service.UserService; @Service public class UserServiceImpl implements UserService { @Autowired private UserDao userDao; public void insert(User user) { userDao.insert(user); } } ``` ## 12:编写Controller类UserController ``` package controller; import com.sun.codemodel.internal.JMethod; import domain.User; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Controller; import org.springframework.web.bind.annotation.*; import service.UserService; @Controller @RequestMapping("user") public class UserController { @Autowired private UserService userService; @ResponseBody @RequestMapping(value = "register" ,method = RequestMethod.POST) public String insert(User user){ userService.insert(user); return "success"; } } ``` ## 13:编写index.html ``` <!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Register</title> </head> <body> <form action="/user/register" method="post"> <input type="text" name="username"> <input type="text" name="tel"> <input type="password" name="password"> <input type="submit"> </form> </body> </html> ``` ## 14:编写pages文件夹下的success.html ``` <!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Success</title> </head> <body> <h3>Success!...</h3> </body> </html> ```
搭建SSM框架中,controller无法实现页面跳转?
今天接触SSM框架的第三天,终于通过篇博客成功的搭建好了SSM框架, 后台Mybatis生成dao、entity和mapper后,测试成功,能够正常读写数据库了, 但是,在加入页面之后,通过controller不能实现页面的跳转,特求助~~ 访问情况: ![图片说明](https://img-ask.csdn.net/upload/201811/26/1543226209_197712.png) 点击跳转后, ![图片说明](https://img-ask.csdn.net/upload/201811/26/1543226267_945695.png) 出现404的错误,个人认为,可能市没有找到controller 代码: messageController.java ``` @Controller @RequestMapping("/message") public class messageController { @RequestMapping("/rea.md") public String gotest(){ System.out.println("执行到这里了"); return "reach"; } @Resource private MessageMapper mapper; @RequestMapping("showUser.md") public void selectUser(HttpServletRequest request, HttpServletResponse response) throws IOException { request.setCharacterEncoding("UTF-8"); response.setCharacterEncoding("UTF-8"); int userID = Integer.parseInt(request.getParameter("id")); Message message = mapper.selectByPrimaryKey(userID); System.out.println(message.getCommand()+message.getContent()+message.getDescription()); } } ``` index.jsp ``` <%@page contentType="text/html; charset=UTF-8" language="java" %> <html> <head> <title>首页</title> </head> <body> <h2>Hello World!</h2> <a href="/message/rea.md">点击跳转</a> <p id="test">Hello World!</p> <button type="button" onclick="selectUser()">onclick test</button> </body> </html> ``` reach.jsp ``` <%@ page contentType="text/html;charset=UTF-8" language="java" %> <html> <head> <title>跳到这里了</title> </head> <body> 跳转成功!!! </body> </html> ``` 文件路径: ![图片说明](https://img-ask.csdn.net/upload/201811/26/1543226677_526125.png)
ssm框架使用注解注入失败
![图片说明](https://img-ask.csdn.net/upload/201605/27/1464332870_733703.png) <!-- 加载db.properties文件中的内容,db.properties文件中的key要有一定的特殊规则 --> <context:property-placeholder location="classpath:jdbc.properties"/> <!-- 扫描标注@Repository注解的service --> <context:component-scan base-package="cn.bdqn.ssm.service.impl.*"/> <!--数据源配置 --> <bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource" > <property name="url" value="${jdbc.url}"></property> <property name="username" value="${jdbc.username}"></property> <property name="password" value="${jdbc.password}"></property> <property name="driverClassName" value="${jdbc.driverClass}"></property> </bean> <!-- SessionFactory配置 --> <!-- 配置SqlSessionFactory ,整合spring和MyBatis,使其完美结合--> <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean"> <!-- 数据源 --> <property name="dataSource" ref="dataSource"/> <!-- 自动扫描entity目录,省掉手动配置映射文件--> <property name="mapperLocations" value="classpath:cn/bdqn/ssm/mapping/*.xml" /> </bean> <!-- 配置Mapper扫描器 --> <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer"> <!-- 扫描包路径,如果需要扫描多个包中间用半角逗号隔开 --> <property name="basePackage" value="cn.bdqn.ssm.dao"/> <!-- 这边不能使用ref="sqlSessionFactory"原因是因为上面加载配置文件导致这边引用会报错 --> <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory" /> </bean> <!-- 事务管理器 对mybatis操作数据库事务控制,spring使用jdbc的事务控制类 --> <bean id="txManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager"> <!-- <property name="sqlSessionFactoryBeanName" ref="sqlSessionFactory"></property> --> <!-- 数据源 dataSource在applicationContext-dao.xml中配置了 --> <property name="dataSource" ref="dataSource" /> </bean> <!-- 配置事务增强 --> <tx:advice id="txAdvice" transaction-manager="txManager"> <tx:attributes> <tx:method name="registe*" propagation="REQUIRED"/> <tx:method name="insert*" propagation="REQUIRED"/> <tx:method name="update*" propagation="REQUIRED"/> <tx:method name="del*" propagation="REQUIRED"/> <tx:method name="delete*" propagation="REQUIRED"/> <tx:method name="remove*" propagation="REQUIRED"/> <tx:method name="add*" propagation="REQUIRED"/> <tx:method name="save*" propagation="REQUIRED"/> <tx:method name="modify*" propagation="REQUIRED"/> <tx:method name="find*" read-only="true"/> <tx:method name="get*" read-only="true"/> <tx:method name="load*" read-only="true"/> <tx:method name="login*" read-only="true"/> </tx:attributes> </tx:advice> <aop:config> <aop:pointcut expression="execution(* cn.bdqn.ssm.service.impl.*.*(..))" id="pointCut"/> <aop:advisor advice-ref="txAdvice" pointcut-ref="pointCut"/> </aop:config> </beans>
JAVA 如何连接JanusGraph
例如SSM框架一样,通过配置文件连接到数据库。那么如何连接到JanusGraph呢, 用janusgraph-hbase这个包
SSM框架——使用MyBatis Generator自动创建代码不成功
看的这个教程:http://blog.csdn.net/zhshulin/article/details/23912615 照着做配置也不成功,有些疑问 1,我看楼主的cmd命令,貌似他并没有把那几个jar包导入项目里啊,还是一个下载文件夹的路径,我也把他提供下载的这个文件夹,随便放在了D盘里,并按他说的,把generatorConfig.xml和这几个jar包放一起,我都不知道我在做什么( ╯□╰ ) 2,他的配置文件的第七行: <classPathEntry location="mysql-connector-java-5.1.25-bin.jar"/> ,引入了mysql数据库连接的jar包,这个jar包我在我的maven项目里下载过了,于是照猫画虎的写<classPathEntry location="mysql-connector-java-5.1.34.jar" />,然后命令行输入楼主指定的那段命令后报错,找不到我这个数据库连接: ![图片说明](https://img-ask.csdn.net/upload/201606/15/1466004330_112612.jpg) 这个数据库连接到底该怎么配啊?他光配了个jar文件名字也没说清楚
在ssm框架中自定义日志切面logAspect拦截控制器加入cglib识别项目很卡?
![通过模仿 http://www.cnblogs.com/leifei/p/6094673.html 里的做法,在项目中实现日志记录存储到数据库,项目启动后对java文件等其他文件点击或修改里面的方法都卡一顿卡一顿的,求高手解析,](https://img-ask.csdn.net/upload/201709/07/1504755777_426866.png)
IDEA做SSM框架整合时,出现无法加载mapper,导致无法注入。
今日学习SSM框架整合,整合以后,单独用测试类可以连接成功连接数据库,可是一加入MVC用TOMCAT启动,项目就会报错,错误内容为:Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)} 以下为项目各部分截图,有没有大佬帮我分析下,问题到底出在哪? ========================================================================================================================================== ![项目报错详细情况](https://img-ask.csdn.net/upload/201908/15/1565880941_652575.png) ## 项目报错详细情况 ![spring配置文件已经配置了mapper.xml路径和齐对应的接口扫描包](https://img-ask.csdn.net/upload/201908/15/1565880955_958792.png) ## spring配置文件已经配置了mapper.xml路径和齐对应的接口扫描包 ![编译文件夹target里已经编译出了mapper相关配置文件及接口类](https://img-ask.csdn.net/upload/201908/15/1565881099_526884.png) ## 编译文件夹target里已经编译出了mapper相关配置文件及接口类 ![mapper.xml里的namespace已经指明了接口路径](https://img-ask.csdn.net/upload/201908/15/1565881139_161198.png) ## mapper.xml里的namespace已经指明了接口路径 ![pom文件里也配置了resource源](https://img-ask.csdn.net/upload/201908/15/1565881159_416309.png) ## pom文件里也配置了resource源 ========================================================================================================================================== # 详细代码已经贴在下方,只选了几个配置文件及mapper接口类,service及controller应该没关系就没传! ============================================= # mybatis-config.xml ``` <?xml version="1.0" encoding="UTF-8" ?> <!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN" "http://mybatis.org/dtd/mybatis-3-config.dtd"> <configuration> <!--添加缓存 引入第三方二级缓存 --> <settings> <setting name="mapUnderscoreToCamelCase" value="true"/> <setting name="cacheEnabled" value="false"/> </settings> <!-- 配置数据源 default默认使用的数据源 --> <environments default="mysql"> <environment id="mysql"> <transactionManager type="JDBC" /> <dataSource type="POOLED"> <property name="driverClassName" value="com.mysql.jdbc.Driver"/> <property name="url" value="jdbc:mysql:///orderuser"/> <property name="username" value="zhijia3278"/> <property name="password" value="0528"/> </dataSource> </environment> </environments> <!-- 映射文件 --> <mappers> <mapper resource="OrderUserMapper.xml"/> </mappers> </configuration> ``` # OrderUserMapper.java ``` package cn.tedu.mapper; import cn.tedu.domain.Order; import cn.tedu.domain.User; public interface OrderUserMapper { public User queryUser(String userId); public Order queryOrder(String orderId); public void updateUserPoints(User user); } ``` # OrderUserMapper.xml ``` <?xml version="1.0" encoding="UTF-8" ?> <!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd"> <mapper namespace="cn.tedu.mapper.OrderUserMapper"> <select id="queryUser" parameterType="String" resultType="User"> select * from t_user where user_id=#{userId} </select> <select id="queryOrder" parameterType="String" resultType="Order"> select * from t_order where order_id=#{orderId} </select> <update id="updateUserPoints" parameterType="User"> update t_user set points=#{points} where user_id=#{userId} </update> </mapper> ``` # spring.xml ``` <?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:aop="http://www.springframework.org/schema/aop" xmlns:p="http://www.springframework.org/schema/p" xmlns:util="http://www.springframework.org/schema/util" xmlns:context="http://www.springframework.org/schema/context" xmlns:mvc="http://www.springframework.org/schema/mvc" xsi:schemaLocation=" http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd"> <!-- 配置内容 --> <context:component-scan base-package="cn.tedu"> </context:component-scan> <context:annotation-config></context:annotation-config> <!-- 持久层数据源 --> <bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource"> <!-- 4个属性 --> <property name="driverClassName" value="com.mysql.jdbc.Driver"/> <property name="url" value="jdbc:mysql:///orderuser"/> <property name="username" value="zhijia3278"/> <property name="password" value="0528"/> </bean> <!-- sqlSession --> <bean id="sqlSession" class="org.mybatis.spring.SqlSessionFactoryBean"> <!-- 数据源注入 --> <property name="dataSource" ref="dataSource"/> <!-- 扫描mybatis的独立配置文件 关闭二级缓存,驼峰命名 --> <property name="configLocation" value="classpath:mybatis/mybatis-config.xml"/> <!-- 映射文件扫描 --> <property name="mapperLocations" value="classpath:mapper/OrderUserMapper.xml" /> <!-- 别名包 --> <property name="typeAliasesPackage" value="cn.tedu.domain"></property> </bean> <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer"> <!-- 扫描的接口包 cn.tedu.mapper --> <property name="basePackage" value="cn.tedu.mapper"/> </bean> <!-- 注解驱动开启,@RequestMapping @RequestParam等 --> <mvc:annotation-driven/> <!-- 防止静态文件js css html访问被dispacherServlet拦截 --> <!-- localhost静态文件根目录 /static /js /css --> <!-- mapping 满足什么样子的访问地址 http://localhost:8080/js//1.js --> <mvc:resources location="/" mapping="/**"></mvc:resources> </beans> ``` # springmvc-servlet ``` <?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:aop="http://www.springframework.org/schema/aop" xmlns:p="http://www.springframework.org/schema/p" xmlns:util="http://www.springframework.org/schema/util" xmlns:context="http://www.springframework.org/schema/context" xmlns:mvc="http://www.springframework.org/schema/mvc" xsi:schemaLocation=" http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd"> <!-- 配置内容 --> <context:component-scan base-package="cn.tedu"/> <!-- 注解驱动开启,@RequestMapping @RequestParam等 --> <mvc:annotation-driven/> <!-- 防止静态文件js css html访问被dispacherServlet拦截 --> <!-- localhost静态文件根目录 /static /js /css --> <!-- mapping 满足什么样子的访问地址 http://localhost:8080/js//1.js --> <mvc:resources location="/" mapping="/**"></mvc:resources> </beans> ``` # web.xml ``` <!DOCTYPE web-app PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN" "http://java.sun.com/dtd/web-app_2_3.dtd" > <web-app> <display-name>Archetype Created Web Application</display-name> <servlet> <servlet-name>springmvc</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <!-- tomcat启动加载spring.xml --> <!-- <init-param>--> <!-- <param-name>contextConfigLocation</param-name>--> <!-- <param-value>classpath:springmvc/springmvc-servlet.xml</param-value>--> <!-- </init-param>--> </servlet> <servlet-mapping> <servlet-name>springmvc</servlet-name> <url-pattern>/</url-pattern> </servlet-mapping> </web-app> ``` # pom.xml ``` <?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>cn.tedu</groupId> <artifactId>SSMDemo</artifactId> <version>1.0-SNAPSHOT</version> <packaging>war</packaging> <name>SSM-DEMO01 Maven Webapp</name> <url>http://maven.apache.org</url> <dependencies> <!-- <dependency>--> <!-- <groupId>junit</groupId>--> <!-- <artifactId>junit</artifactId>--> <!-- <version>4.12</version>--> <!-- <scope>compile</scope>--> <!-- </dependency>--> <dependency> <groupId>junit</groupId> <artifactId>junit</artifactId> <version>4.12</version> <scope>test</scope> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-context</artifactId> <version>4.3.13.RELEASE</version> </dependency> <!-- datasource --> <dependency> <groupId>com.alibaba</groupId> <artifactId>druid</artifactId> <version>1.0.14</version> </dependency> <!-- spring mysql --> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-jdbc</artifactId> <version>4.3.13.RELEASE</version> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>5.0.8</version> </dependency> <!-- mybatis --> <dependency> <groupId>org.mybatis</groupId> <artifactId>mybatis</artifactId> <version>3.4.5</version> </dependency> <!-- spring mybatis --> <dependency> <groupId>org.mybatis</groupId> <artifactId>mybatis-spring</artifactId> <version>1.3.1</version> </dependency> <!-- springmvc --> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-web</artifactId> <version>4.3.13.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-webmvc</artifactId> <version>4.3.13.RELEASE</version> </dependency> <!-- jackson --> <dependency> <groupId>com.fasterxml.jackson.core</groupId> <artifactId>jackson-core</artifactId> <version>2.8.8</version> </dependency> <dependency> <groupId>com.fasterxml.jackson.core</groupId> <artifactId>jackson-core</artifactId> <version>2.8.8</version> </dependency> <dependency> <groupId>com.fasterxml.jackson.core</groupId> <artifactId>jackson-databind</artifactId> <version>2.8.8</version> </dependency> <dependency> <groupId>javax.servlet</groupId> <artifactId>javax.servlet-api</artifactId> <version>3.1.0</version> <scope>provided</scope> </dependency> </dependencies> <build> <finalName>SSM-DEMO01</finalName> <plugins> <plugin> <groupId>org.apache.tomcat.maven</groupId> <artifactId>tomcat7-maven-plugin</artifactId> <version>2.2</version> <!-- 插件属性配置 --> <configuration> <!-- 端口 --> <port>8080</port> <!-- 项目访问路径 --> <path>/</path> <!-- 编解码 --> <uriEncoding>utf-8</uriEncoding> <useBodyEncodingForURI>true</useBodyEncodingForURI> </configuration> </plugin> </plugins> <resources> <resource> <directory>resource</directory> <includes> <include>**/*.xml</include> <include>mapper/*.xml</include> <include>mybatis/*.xml</include> <include>spring/*.xml</include> </includes> <!-- <filtering>true</filtering>--> </resource> </resources> </build> </project> ```
SSM框架中,怎么通过controller实现页面的跳转?
今天接触SSM框架的第四天,后台Mybatis生成dao、entity和mapper后,测试成功,能够正常读写数据库了,但是,在加入页面之后,通过controller不能实现页面的跳转,特求助~~ 访问情况: ![图片说明](https://img-ask.csdn.net/upload/201811/27/1543304296_872148.png) 点击跳转后, ![图片说明](https://img-ask.csdn.net/upload/201811/27/1543304328_484707.png) 出现404的错误,个人认为,可能是没有找到controller 代码: messageController.java ``` @Controller public class messageController { @RequestMapping("/message/go") public String gotest(){ return "second"; } } ``` index.jsp ``` <%@page contentType="text/html; charset=UTF-8" language="java" %> <html> <head> <title>首页</title> </head> <body> <h2>Hello World!</h2> <a href="/message/go">点击跳转</a> <p id="test">Hello World!</p> <button type="button" onclick="selectUser()">onclick test</button> </body> </html> ``` reach.jsp ``` <%@ page contentType="text/html;charset=UTF-8" language="java" %> <html> <head> <title>跳到这里了</title> </head> <body> 跳转成功!!! </body> </html> ``` 文件路径: ![图片说明](https://img-ask.csdn.net/upload/201811/27/1543304458_62372.png) SpringMVC的配置 ``` <?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context" xmlns:beans="http://www.springframework.org/schema/beans" xmlns:mvc="http://www.springframework.org/schema/mvc" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.3.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.3.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.3.xsd"> <!-- ①:top.xiaofeng包中的所有类进行扫描,以完成Bean创建和自动依赖注入的功能 --> <context:component-scan base-package="top.xiaofeng"/> <mvc:annotation-driven/> <!-- 静态资源访问 --> <!--如果webapp下你新建了文件夹,想访问里面的静态资源,那么就要在这配置一下--> <mvc:resources location="/img/" mapping="/img/**"/> <mvc:resources location="/css/" mapping="/css/**"/> <mvc:resources location="/js/" mapping="/js/**"/> <!-- ②:启动Spring MVC的注解功能,完成请求和注解POJO的映射 --> <bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter"> <property name="messageConverters"> <list> <ref bean="mappingJacksonHttpMessageConverter"/> </list> </property> </bean> <bean id="mappingJacksonHttpMessageConverter" class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter"> <property name="supportedMediaTypes"> <list> <value>application/json;charset=UTF-8</value> </list> </property> </bean> <!-- 配置视图解析器,把控制器的逻辑视频映射为真正的视图 --> <!-- /WEB-INF/views/second.jsp --> <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver"> <property name="viewClass" value="org.springframework.web.servlet.view.JstlView"/> <property name="prefix" value="/views/"/> <property name="suffix" value=".jsp"/> </bean> <!-- 拦截器 --> <mvc:interceptors> <!-- 国际化操作拦截器 如果采用基于(请求/Session/Cookie)则必需配置 --> <bean class="org.springframework.web.servlet.i18n.LocaleChangeInterceptor"/> </mvc:interceptors> <!-- 定义无Controller的path<->view直接映射 --> <!-- <mvc:view-controller path="/" view-name="redirect:/" /> --> </beans> ``` web.xml配置 ``` <?xml version="1.0" encoding="UTF-8"?> <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" version="3.0"> <display-name>mydemo</display-name> <!-- 配置编码方式--> <filter> <filter-name>encodingFilter</filter-name> <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class> <init-param> <param-name>encoding</param-name> <param-value>UTF-8</param-value> </init-param> <init-param> <param-name>forceEncoding</param-name> <param-value>true</param-value> </init-param> </filter> <filter-mapping> <filter-name>encodingFilter</filter-name> <url-pattern>/*</url-pattern> </filter-mapping> <!-- 配置springmvc的前端控制器 指向spring-mvc.xml 程序在启动的时候就加载springmvc 可以接受所有请求 load-on-startup:表示启动容器时初始化该Servlet; --> <servlet> <servlet-name>springServlet</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <!-- 可以自定义servlet.xml配置文件的位置和名称, 默认为WEB-INF目录下,名称为[<servlet-name>]-servlet.xml,如spring-servlet.xml --> <init-param> <param-name>contextConfigLocation</param-name> <param-value>classpath:spring/spring-mvc.xml</param-value> </init-param> <load-on-startup>1</load-on-startup> </servlet> <!-- 将前端URL请求和后台处理方法controller建立对应关系--> <servlet-mapping> <servlet-name>springServlet</servlet-name> <url-pattern>/</url-pattern> </servlet-mapping> <!-- 取消对某一类文件的拦截--> <servlet-mapping> <servlet-name>default</servlet-name> <url-pattern>*.md</url-pattern> </servlet-mapping> <!-- Spring配置 --> <listener> <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class> </listener> <context-param> <param-name>contextConfigLocation</param-name> <param-value>classpath:spring/applicationContext.xml</param-value> </context-param> <!-- 欢迎页面--> <welcome-file-list> <welcome-file>/index.jsp</welcome-file> </welcome-file-list> <!--&lt;!&ndash;404错误展示页面&ndash;&gt;--> <!--<error-page>--> <!--<error-code>404</error-code>--> <!--<location>/404.jsp</location>--> <!--</error-page>--> <!--设置session失效时间为30分钟 --> <session-config> <session-timeout>600</session-timeout> </session-config> </web-app> ```
java 怎么实现收发json数据并保存到数据库里,还有超时条件?
1. 1. 具体思路:服务器设置端口→连接客户端→收发json数据→数据保存到数据库→关闭连接→关闭服务器 1. 2. 超时条件:服务端开始等候客户端连接的同时计时,在10秒内连接成功就继续进行下一步的收发数据,超时了就关闭连接;开始第一次的收发数据的同时计时20秒,超时就断开连接,在20秒内收发数据成功,就继续循环第一次的收发数据的流程 1. 3. json数据是从客户端发过来的,不是什么json文件 1. 4. 已经写好的代码看网址https://blog.csdn.net/m0_37690540/article/details/86533744 1. 5. 弄完了 换到SSM框架下,需要修改什么?
mybatis如何在xml文件创建视图啊
mybatis如何在xml文件创建视图啊 , 用的mysql数据库,还是说ssm框架无法在xml 配置视图,表啊。。。必须要在数据库里面创建啊,我以前用的ofbiz框架就可以啊~
基于ssm框架开发的项目,在service层测试时发生错误,求指点?
基于ssm框架开发的项目,在做service层测试时发生错误,如下: ``` 五月 11, 2018 3:19:54 下午 org.springframework.test.context.support.DefaultTestContextBootstrapper getDefaultTestExecutionListenerClassNames 信息: Loaded default TestExecutionListener class names from location [META-INF/spring.factories]: [org.springframework.test.context.web.ServletTestExecutionListener, org.springframework.test.context.support.DirtiesContextBeforeModesTestExecutionListener, org.springframework.test.context.support.DependencyInjectionTestExecutionListener, org.springframework.test.context.support.DirtiesContextTestExecutionListener, org.springframework.test.context.transaction.TransactionalTestExecutionListener, org.springframework.test.context.jdbc.SqlScriptsTestExecutionListener] 五月 11, 2018 3:19:54 下午 org.springframework.test.context.support.DefaultTestContextBootstrapper getTestExecutionListeners 信息: Using TestExecutionListeners: [org.springframework.test.context.web.ServletTestExecutionListener@4cb2c100, org.springframework.test.context.support.DirtiesContextBeforeModesTestExecutionListener@6fb554cc, org.springframework.test.context.support.DependencyInjectionTestExecutionListener@614c5515, org.springframework.test.context.support.DirtiesContextTestExecutionListener@77b52d12, org.springframework.test.context.transaction.TransactionalTestExecutionListener@2d554825, org.springframework.test.context.jdbc.SqlScriptsTestExecutionListener@68837a77] 五月 11, 2018 3:19:55 下午 org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions 信息: Loading XML bean definitions from class path resource [spring/spring-dao.xml] 五月 11, 2018 3:19:55 下午 org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions 信息: Loading XML bean definitions from class path resource [spring/spring-service.xml] 五月 11, 2018 3:19:55 下午 org.springframework.test.context.TestContextManager prepareTestInstance 严重: Caught exception while allowing TestExecutionListener [org.springframework.test.context.support.DependencyInjectionTestExecutionListener@614c5515] to prepare test instance [com.imooc.o2o.service.AreaServiceTest@2353b3e6] java.lang.IllegalStateException: Failed to load ApplicationContext at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContext(DefaultCacheAwareContextLoaderDelegate.java:124) at org.springframework.test.context.support.DefaultTestContext.getApplicationContext(DefaultTestContext.java:83) at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.injectDependencies(DependencyInjectionTestExecutionListener.java:117) at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.prepareTestInstance(DependencyInjectionTestExecutionListener.java:83) at org.springframework.test.context.TestContextManager.prepareTestInstance(TestContextManager.java:230) at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.createTest(SpringJUnit4ClassRunner.java:228) at org.springframework.test.context.junit4.SpringJUnit4ClassRunner$1.runReflectiveCall(SpringJUnit4ClassRunner.java:287) at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12) at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.methodBlock(SpringJUnit4ClassRunner.java:289) at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:247) at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:94) at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290) at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71) at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288) at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58) at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268) at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61) at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:70) at org.junit.runners.ParentRunner.run(ParentRunner.java:363) at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:191) at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:86) at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:459) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:678) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:382) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:192) Caused by: org.springframework.beans.factory.BeanDefinitionStoreException: IOException parsing XML document from class path resource [spring/spring-service.xml]; nested exception is java.io.FileNotFoundException: class path resource [spring/spring-service.xml] cannot be opened because it does not exist at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions(XmlBeanDefinitionReader.java:344) at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions(XmlBeanDefinitionReader.java:304) at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:181) at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:217) at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:188) at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:252) at org.springframework.test.context.support.AbstractGenericContextLoader.loadBeanDefinitions(AbstractGenericContextLoader.java:257) at org.springframework.test.context.support.AbstractGenericContextLoader.loadContext(AbstractGenericContextLoader.java:124) at org.springframework.test.context.support.AbstractGenericContextLoader.loadContext(AbstractGenericContextLoader.java:60) at org.springframework.test.context.support.AbstractDelegatingSmartContextLoader.delegateLoading(AbstractDelegatingSmartContextLoader.java:108) at org.springframework.test.context.support.AbstractDelegatingSmartContextLoader.loadContext(AbstractDelegatingSmartContextLoader.java:251) at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContextInternal(DefaultCacheAwareContextLoaderDelegate.java:98) at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContext(DefaultCacheAwareContextLoaderDelegate.java:116) ... 25 more Caused by: java.io.FileNotFoundException: class path resource [spring/spring-service.xml] cannot be opened because it does not exist at org.springframework.core.io.ClassPathResource.getInputStream(ClassPathResource.java:172) at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions(XmlBeanDefinitionReader.java:330) ... 37 more ``` service实现类代码如下: package com.imooc.o2o.service.impl; import java.util.List; import javax.annotation.Resource; import org.springframework.stereotype.Service; import com.imooc.o2o.dao.AreaDao; import com.imooc.o2o.entity.Area; import com.imooc.o2o.service.AreaService; @Service public class AreaServiceImpl implements AreaService { @Resource private AreaDao areaDao; public List<Area> getAreaList() { return areaDao.queryArea(); } } service 配置文件代码如下: ``` <?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context" xmlns:tx="http://www.springframework.org/schema/tx" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd"> <!-- 扫描service包下所有使用注解的类型 --> <context:component-scan base-package="com.imooc.o2o.service"/> <!-- 配置事务管理器 --> <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager"> <!-- 注入数据库连接池 --> <property name="dataSource" ref="dataSource"/> </bean> <!-- 配置基于注解的声明式事务 --> <tx:annotation-driven transaction-manager="transactionManager"/> </beans> ```
ssm框架连接配置applicationContext.xml运行时报错
**严重: Exception sending context initialized event to listener instance of class org.springframework.web.context.ContextLoaderListener org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.mybatis.spring.mapper.MapperScannerConfigurer#0' defined in class path resource [applicationContext.xml]: Initialization of bean failed; nested exception is java.lang.NoClassDefFoundError: org/apache/ibatis/session/SqlSessionFactory** at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:547) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:475) at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:302) at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:228) at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:298) at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:198) at org.springframework.context.support.PostProcessorRegistrationDelegate.invokeBeanFactoryPostProcessors(PostProcessorRegistrationDelegate.java:116) at org.springframework.context.support.AbstractApplicationContext.invokeBeanFactoryPostProcessors(AbstractApplicationContext.java:609) at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:464) at org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext(ContextLoader.java:403) at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:306) at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:106) at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4727) at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5189) at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150) at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:752) at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:728) at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:734) at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:1107) at org.apache.catalina.startup.HostConfig$DeployDirectory.run(HostConfig.java:1841) at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:514) at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264) at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1135) at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635) at java.base/java.lang.Thread.run(Thread.java:844) **Caused by: java.lang.NoClassDefFoundError: org/apache/ibatis/session/SqlSessionFactory** at java.base/java.lang.Class.getDeclaredMethods0(Native Method) at java.base/java.lang.Class.privateGetDeclaredMethods(Class.java:3119) at java.base/java.lang.Class.privateGetPublicMethods(Class.java:3144) at java.base/java.lang.Class.getMethods(Class.java:1863) at org.springframework.beans.ExtendedBeanInfoFactory.supports(ExtendedBeanInfoFactory.java:54) at org.springframework.beans.ExtendedBeanInfoFactory.getBeanInfo(ExtendedBeanInfoFactory.java:46) at org.springframework.beans.CachedIntrospectionResults.<init>(CachedIntrospectionResults.java:275) at org.springframework.beans.CachedIntrospectionResults.forClass(CachedIntrospectionResults.java:188) at org.springframework.beans.BeanWrapperImpl.getCachedIntrospectionResults(BeanWrapperImpl.java:327) at org.springframework.beans.BeanWrapperImpl.getPropertyDescriptorInternal(BeanWrapperImpl.java:359) at org.springframework.beans.BeanWrapperImpl.isWritableProperty(BeanWrapperImpl.java:438) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyPropertyValues(AbstractAutowireCapableBeanFactory.java:1458) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1197) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:537) ... 24 more **Caused by: java.lang.ClassNotFoundException: org.apache.ibatis.session.SqlSessionFactory** at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1285) at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1119) ... 38 more db.properties文件,mysql8.0 ``` jdbc_username=root jdbc_password=aaa jdbc_driver=com.mysql.cj.jdbc.Driver jdbc_url=jdbc\:mysql\://localhost\:3306/aaaaa_db?useSSL\=false&serverTimezone\=GMT ``` applicationContext.xml代码如下 ``` <?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p" xmlns:context="http://www.springframework.org/schema/context" xmlns:tx="http://www.springframework.org/schema/tx" xmlns:aop="http://www.springframework.org/schema/aop" xsi:schemaLocation= "http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.1.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd"> <!-- 配置扫描包 --> <context:component-scan base-package="com.ls.dao"/> <context:component-scan base-package="com.ls.service"/> <!-- 数据库连接相关配置 --> <!-- 加载配置文件 --> <context:property-placeholder location="classpath:conf/db.properties" /> <!-- 数据库连接池 --> <bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource" destroy-method="close"> <property name="url" value="${jdbc_url}" /> <property name="username" value="${jdbc_username}" /> <property name="password" value="${jdbc_password}" /> <property name="driverClassName" value="${jdbc_driver}" /> <property name="maxActive" value="10" /> <property name="minIdle" value="5" /> </bean> <!-- 配置mybatis的sqlSessionFactory --> <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean"> <property name="dataSource" ref="dataSource"/> <!-- 配置自动扫描mapper.xml文件 --> <property name="mapperLocations" value="classpath:com/ls/mapper/*.xml"/> <!-- mybatis的配置文件 --> <property name="configLocation" value="classpath:mybatis-config.xml"/> </bean> <!-- Dao接口所在包名,Spring会自动查找其下的类 --> <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer"> <property name="basePackage" value="com.ls.dao"/> <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"/> </bean> <!-- 配置事务管理器 --> <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager"> <property name="dataSource" ref="dataSource"/> </bean> <!-- 配置事务管理器管理哪些方法 --> <!-- 配置事务通知属性 --> <tx:advice id="txAdvice" transaction-manager="transactionManager"> <!-- 定义事务传播属性 --> <tx:attributes> <tx:method name="insert*" propagation="REQUIRED" /> <tx:method name="add*" propagation="REQUIRED" /> <tx:method name="update*" propagation="REQUIRED" /> <tx:method name="upd*" propagation="REQUIRED" /> <tx:method name="save*" propagation="REQUIRED" /> <tx:method name="query*" propagation="REQUIRED" read-only="true" /> <tx:method name="get*" propagation="REQUIRED" read-only="true" /> <tx:method name="find*" propagation="REQUIRED" read-only="true" /> <tx:method name="*" propagation="REQUIRED" read-only="true" /> </tx:attributes> </tx:advice> <!-- 配置具体那些包下面的那些类下面的那些方法进行事务管理器 --> <aop:config> <aop:pointcut id="servicePoint" expression="execution(* com.service.*.*(..))" /> <aop:advisor advice-ref="txAdvice" pointcut-ref="servicePoint"/> </aop:config> </beans> ```
SSM框架在tomcat7下跑一段时间后抛异常,怀疑是Mysql 8小时连接问题。
框架是Spring+SpringMVC+MyBatis 在Tomcat7上发布后跑大约四个小时后会抛一次异常,但是能正常访问 配置文件: proxool.prototypeCount=5 proxool.maximumActiveTime=300000 proxool.maximumConnectionLifetime=18000000 proxool.minimumConnectionCount=5 proxool.maximumConnectionCount=40 proxool.alias=lvseu proxool.simultaneous-build-throttle=20 proxool.prototype-count=2 proxool.houseKeepingTestSql=select CURRENT_DATE proxool.hourseKeepingSleepTime=30000 <property name="driver" value="${connection.driver_class}" /> <property name="driverUrl" value="${connection.url}" /> <property name="user" value="${connection.username}" /> <property name="password" value="${connection.password}" /> <!-- 测试的SQL执行语句 --> <property name="houseKeepingTestSql" value="${proxool.houseKeepingTestSql}"/> <!-- 最少保持的空闲连接数 (默认2个) --> <property name="prototypeCount" value="${proxool.prototypeCount}" /> <!-- 最大活动时间(超过此时间线程将被kill,默认为5分钟) --> <property name="maximumActiveTime" value="${proxool.maximumActiveTime}" /> <!-- 最小连接数 (默认2个) --> <property name="minimumConnectionCount" value="${proxool.minimumConnectionCount}" /> <!-- 最大连接数 (默认10个) --> <property name="maximumConnectionCount" value="${proxool.maximumConnectionCount}" /> <!-- 连接最长时间(默认为4个小时) --> <property name="maximumConnectionLifetime" value="${proxool.maximumConnectionLifetime}" /> <!-- 数据库别名 --> <property name="alias" value="${proxool.alias}" /> <!-- proxool自动侦察各个连接状态的时间间隔(毫秒),侦察到空闲的连接就马上回收,超时的销毁 默认30秒) --> <property name="houseKeepingSleepTime" value="${proxool.hou rseKeepingSleepTime}" /> 抛的异常为: 2017-08-10 03:20:22 [Prototyper] ERROR org.logicalcobwebs.proxool.lvseu - Prototype com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to database server. Attempted reconnect 3 times. Giving up. at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) at java.lang.reflect.Constructor.newInstance(Constructor.java:526) at com.mysql.jdbc.Util.handleNewInstance(Util.java:406) at com.mysql.jdbc.Util.getInstance(Util.java:381) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:984) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:956) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:926) at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2270) at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:723) at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:46) at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) at java.lang.reflect.Constructor.newInstance(Constructor.java:526) at com.mysql.jdbc.Util.handleNewInstance(Util.java:406) at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:302) at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:282) at java.sql.DriverManager.getConnection(DriverManager.java:571) at java.sql.DriverManager.getConnection(DriverManager.java:187) at org.logicalcobwebs.proxool.DefaultConnectionBuilder.buildConnection(DefaultConnectionBuilder.java:39) at org.logicalcobwebs.proxool.Prototyper.buildConnection(Prototyper.java:159) at org.logicalcobwebs.proxool.Prototyper.sweep(Prototyper.java:102) at org.logicalcobwebs.proxool.PrototyperThread.run(PrototyperThread.java:44) Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure Last packet sent to the server was 0 ms ago. at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) at java.lang.reflect.Constructor.newInstance(Constructor.java:526) at com.mysql.jdbc.Util.handleNewInstance(Util.java:406) at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1074) at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:335) at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2194) ... 15 more Caused by: java.net.ConnectException: Connection timed out: connect at java.net.DualStackPlainSocketImpl.connect0(Native Method) at java.net.DualStackPlainSocketImpl.socketConnect(DualStackPlainSocketImpl.java:79) at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:339) at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:200) at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:182) at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:172) at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392) at java.net.Socket.connect(Socket.java:579) at java.net.Socket.connect(Socket.java:528) at java.net.Socket.<init>(Socket.java:425) at java.net.Socket.<init>(Socket.java:241) at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:253) at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:284) ... 16 more 2017-08-10 03:20:46 [Prototyper] ERROR org.logicalcobwebs.proxool.lvseu - Prototype com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to database server. Attempted reconnect 3 times. Giving up. at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) at java.lang.reflect.Constructor.newInstance(Constructor.java:526) at com.mysql.jdbc.Util.handleNewInstance(Util.java:406) at com.mysql.jdbc.Util.getInstance(Util.java:381) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:984) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:956) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:926) at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2270) at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:723) at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:46) at sun.reflect.GeneratedConstructorAccessor57.newInstance(Unknown Source) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) at java.lang.reflect.Constructor.newInstance(Constructor.java:526) at com.mysql.jdbc.Util.handleNewInstance(Util.java:406) at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:302) at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:282) at java.sql.DriverManager.getConnection(DriverManager.java:571) at java.sql.DriverManager.getConnection(DriverManager.java:187) at org.logicalcobwebs.proxool.DefaultConnectionBuilder.buildConnection(DefaultConnectionBuilder.java:39) at org.logicalcobwebs.proxool.Prototyper.buildConnection(Prototyper.java:159) at org.logicalcobwebs.proxool.Prototyper.sweep(Prototyper.java:102) at org.logicalcobwebs.proxool.PrototyperThread.run(PrototyperThread.java:44) Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure Last packet sent to the server was 0 ms ago. at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) at java.lang.reflect.Constructor.newInstance(Constructor.java:526) at com.mysql.jdbc.Util.handleNewInstance(Util.java:406) at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1074) at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:335) at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2194) ... 14 more Caused by: java.net.ConnectException: Connection timed out: connect at java.net.DualStackPlainSocketImpl.connect0(Native Method) at java.net.DualStackPlainSocketImpl.socketConnect(DualStackPlainSocketImpl.java:79) at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:339) at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:200) at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:182) at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:172) at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392) at java.net.Socket.connect(Socket.java:579) at java.net.Socket.connect(Socket.java:528) at java.net.Socket.<init>(Socket.java:425) at java.net.Socket.<init>(Socket.java:241) at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:253) at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:284) ... 15 more
对计算机专业来说学历真的重要吗?
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