mybatis mysql xml字段解析

String str = “a-b”,现在 mapper.xml (mybatis)里接收到了 str。
xml里将 str 拆成 字段1 = a and 字段2 = b,
怎么在xml实现?
数据库mysql

1个回答

字段1=substr(str,1,locate('-',str)-1) and 字段2=substr(str,locate('-')+1,length(str))

guzhizang
guzhizang SUBSTRING (#{value},1,ALLOCATE ('-',#{value})-1)
一年多之前 回复
guzhizang
guzhizang xml里没有 locate 这个方法 有allocate 和DEALLOCATE
一年多之前 回复
guzhizang
guzhizang xml
一年多之前 回复
guzhizang
guzhizang 项目;
一年多之前 回复
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exist at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) at java.lang.reflect.Constructor.newInstance(Constructor.java:423) at com.mysql.jdbc.Util.handleNewInstance(Util.java:400) at com.mysql.jdbc.Util.getInstance(Util.java:383) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:980) at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3847) at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3783) at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2447) at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2594) at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2545) at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:1901) at com.mysql.jdbc.PreparedStatement.execute(PreparedStatement.java:1193) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:498) at org.apache.ibatis.logging.jdbc.PreparedStatementLogger.invoke(PreparedStatementLogger.java:59) at com.sun.proxy.$Proxy5.execute(Unknown Source) at org.apache.ibatis.executor.statement.PreparedStatementHandler.query(PreparedStatementHandler.java:63) at org.apache.ibatis.executor.statement.RoutingStatementHandler.query(RoutingStatementHandler.java:79) at org.apache.ibatis.executor.SimpleExecutor.doQuery(SimpleExecutor.java:63) at org.apache.ibatis.executor.BaseExecutor.queryFromDatabase(BaseExecutor.java:324) at org.apache.ibatis.executor.BaseExecutor.query(BaseExecutor.java:156) at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:109) at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:83) at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:148) ... 29 more ``` # SqlMapConfig.xml ``` <?xml version="1.0" encoding="UTF-8" ?> <!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN" "http://mybatis.org/dtd/mybatis-3-config.dtd"> <configuration> <!-- 加载属性文件 --> <properties resource="db.properties"> <!--properties中还可以配置一些属性名和属性值 --> <!-- <property name="jdbc.driver" value=""/> --> </properties> <!-- 全局配置参数,需要时再设置 --> <!-- <settings> </settings> --> <!-- 别名定义 --> <typeAliases> <!-- 针对单个别名定义 type:类型的路径 alias:别名 --> <!-- <typeAlias type="com.neuedu.mybatis.po.User" alias="user"/> --> <!-- 批量别名定义 指定包名,mybatis自动扫描包中的po类,自动定义别名,别名就是类名(首字母大写或小写都可以) --> <package name="com.neuedu.pojo"/> </typeAliases> <!-- 和spring整合后 environments配置将废除--> <environments default="development"> <environment id="development"> <!-- 使用jdbc事务管理,事务控制由mybatis--> <transactionManager type="JDBC" /> <!-- 数据库连接池,由mybatis管理--> <dataSource type="POOLED"> <property name="driver" value="${jdbc.driver}" /> <property name="url" value="${jdbc.url}" /> <property name="username" value="${jdbc.username}" /> <property name="password" value="${jdbc.password}" /> </dataSource> </environment> </environments> <!-- 加载 映射文件 --> <mappers> <mapper resource="sqlmap/User.xml"/> <!--通过resource方法一次加载一个映射文件 --> <!-- <mapper resource="sqlmap/User.xml"/> --> <!-- 通过mapper接口加载单个 映射文件 遵循一些规范:需要将mapper接口类名和mapper.xml映射文件名称保持一致,且在一个目录 中 上边规范的前提是:使用的是mapper代理方法 --> <!-- <mapper class="com.neuedu.mapper.UserMapper"/> --> <!-- 批量加载mapper 指定mapper接口的包名,mybatis自动扫描包下边所有mapper接口进行加载 遵循一些规范:需要将mapper接口类名和mapper.xml映射文件名称保持一致,且在一个目录 中 上边规范的前提是:使用的是mapper代理方法 --> <package name="com.neuedu.mapper"/> </mappers> </configuration> ``` # User ``` public class User { //属性名和数据库表的字段对应 private int id; private String username;// 用户姓名 private String sex;// 性别 private Date birthday;// 生日 private String address;// 地址 public int getId() { return id; } public void setId(int id) { this.id = id; } public String getUsername() { return username; } public void setUsername(String username) { this.username = username; } public String getSex() { return sex; } public void setSex(String sex) { this.sex = sex; } public Date getBirthday() { return birthday; } public void setBirthday(Date birthday) { this.birthday = birthday; } public String getAddress() { return address; } public void setAddress(String address) { this.address = address; } @Override public String toString() { return "User [id=" + id + ", username=" + username + ", sex=" + sex + ", birthday=" + birthday + ", address=" + address + "]"; } } ``` 也不知道为什么,明明已经在UserMapper.xml里面把表名改了,但是报错信息里查找的还是T-user表 求大神指导!感恩! # 问题已解决 在maven文件里加上下面的代码 ``` <resources> <resource> <directory>src/main/java</directory> <includes> <include>**/*Mapper.xml</include> </includes> </resource> </resources> ```
idea配置mybits generate时报错,请问是哪配错了吗?
报错说找不到driver-class-name核对了很多次都没问题啊 报错: ``` D:\jdk1.8.0_121\bin\java.exe -Dmaven.multiModuleProjectDirectory=D:\mycode\demo_mybits\demo "-Dmaven.home=D:\software\idea\IntelliJ IDEA 2018.2.6\plugins\maven\lib\maven3" "-Dclassworlds.conf=D:\software\idea\IntelliJ IDEA 2018.2.6\plugins\maven\lib\maven3\bin\m2.conf" "-javaagent:D:\software\idea\IntelliJ IDEA 2018.2.6\lib\idea_rt.jar=7115:D:\software\idea\IntelliJ IDEA 2018.2.6\bin" -Dfile.encoding=UTF-8 -classpath "D:\software\idea\IntelliJ IDEA 2018.2.6\plugins\maven\lib\maven3\boot\plexus-classworlds-2.5.2.jar" org.codehaus.classworlds.Launcher -Didea.version=2018.2.6 mybatis-generator:generate -e [INFO] Error stacktraces are turned on. [INFO] Scanning for projects... [INFO] [INFO] ------------------------------------------------------------------------ [INFO] Building demo 0.0.1-SNAPSHOT [INFO] ------------------------------------------------------------------------ [INFO] [INFO] --- mybatis-generator-maven-plugin:1.3.2:generate (default-cli) @ demo --- [INFO] Connecting to the Database [INFO] ------------------------------------------------------------------------ [INFO] BUILD FAILURE [INFO] ------------------------------------------------------------------------ [INFO] Total time: 1.637 s [INFO] Finished at: 2019-11-11T09:52:35+08:00 [INFO] Final Memory: 14M/245M [INFO] ------------------------------------------------------------------------ [ERROR] Failed to execute goal org.mybatis.generator:mybatis-generator-maven-plugin:1.3.2:generate (default-cli) on project demo: Execution default-cli of goal org.mybatis.generator:mybatis-generator-maven-plugin:1.3.2:generate failed: Exception getting JDBC Driver: {spring.datasource.driver-class-name} -> [Help 1] org.apache.maven.lifecycle.LifecycleExecutionException: Failed to execute goal org.mybatis.generator:mybatis-generator-maven-plugin:1.3.2:generate (default-cli) on project demo: Execution default-cli of goal org.mybatis.generator:mybatis-generator-maven-plugin:1.3.2:generate failed: Exception getting JDBC Driver at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:212) at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:153) at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:145) at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:116) at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:80) at org.apache.maven.lifecycle.internal.builder.singlethreaded.SingleThreadedBuilder.build(SingleThreadedBuilder.java:51) at org.apache.maven.lifecycle.internal.LifecycleStarter.execute(LifecycleStarter.java:128) at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:307) at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:193) at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:106) at org.apache.maven.cli.MavenCli.execute(MavenCli.java:863) at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:288) at org.apache.maven.cli.MavenCli.main(MavenCli.java:199) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:498) at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced(Launcher.java:289) at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:229) at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:415) at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:356) at org.codehaus.classworlds.Launcher.main(Launcher.java:47) Caused by: org.apache.maven.plugin.PluginExecutionException: Execution default-cli of goal org.mybatis.generator:mybatis-generator-maven-plugin:1.3.2:generate failed: Exception getting JDBC Driver at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:145) at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:207) ... 21 more Caused by: java.lang.RuntimeException: Exception getting JDBC Driver at org.mybatis.generator.internal.db.ConnectionFactory.getDriver(ConnectionFactory.java:85) at org.mybatis.generator.internal.db.ConnectionFactory.getConnection(ConnectionFactory.java:54) at org.mybatis.generator.config.Context.getConnection(Context.java:526) at org.mybatis.generator.config.Context.introspectTables(Context.java:436) at org.mybatis.generator.api.MyBatisGenerator.generate(MyBatisGenerator.java:222) at org.mybatis.generator.maven.MyBatisGeneratorMojo.execute(MyBatisGeneratorMojo.java:203) at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:134) ... 22 more Caused by: java.lang.ClassNotFoundException: {spring.datasource.driver-class-name} at org.codehaus.plexus.classworlds.strategy.SelfFirstStrategy.loadClass(SelfFirstStrategy.java:50) at org.codehaus.plexus.classworlds.realm.ClassRealm.unsynchronizedLoadClass(ClassRealm.java:271) at org.codehaus.plexus.classworlds.realm.ClassRealm.loadClass(ClassRealm.java:247) at org.codehaus.plexus.classworlds.realm.ClassRealm.loadClass(ClassRealm.java:239) at java.lang.Class.forName0(Native Method) at java.lang.Class.forName(Class.java:348) at org.mybatis.generator.internal.ObjectFactory.internalClassForName(ObjectFactory.java:150) at org.mybatis.generator.internal.ObjectFactory.externalClassForName(ObjectFactory.java:121) at org.mybatis.generator.internal.db.ConnectionFactory.getDriver(ConnectionFactory.java:82) ... 28 more [ERROR] [ERROR] Re-run Maven using the -X switch to enable full debug logging. [ERROR] [ERROR] For more information about the errors and possible solutions, please read the following articles: [ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/PluginExecutionException Process finished with exit code 1 ``` application.properties ``` ## 服务器端口,如果不配置默认是8080端口 server.port=9090 ## 数据库设置 spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver spring.datasource.url=jdbc:mysql://localhost:3306/boot_demo?serverTimezone=UTC&useUnicode=true&characterEncoding=utf8 spring.datasource.username=root spring.datasource.password=x5 ## mybatis配置 # 参数类型的包别名设置 mybatis.typeAliasesPackage=com.example.demo.model # 指向映射xml文件目录 mybatis.mapperLocations=classpath:mapper/*.xml pagehelper.helperDialect=mysql pagehelper.reasonable=true pagehelper.supportMethodsArguments=true pagehelper.params=count=countSql ``` 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 https://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.2.0.RELEASE</version> <relativePath/> <!-- lookup parent from repository --> </parent> <groupId>com.example</groupId> <artifactId>demo</artifactId> <version>0.0.1-SNAPSHOT</version> <name>demo</name> <description>Demo project for Spring Boot</description> <properties> <java.version>1.8</java.version> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-jdbc</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.mybatis.spring.boot</groupId> <artifactId>mybatis-spring-boot-starter</artifactId> <version>1.3.2</version> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> <dependency> <groupId>com.github.pagehelper</groupId> <artifactId>pagehelper-spring-boot-starter</artifactId> <version>1.2.10</version> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> <plugin> <groupId>org.mybatis.generator</groupId> <artifactId>mybatis-generator-maven-plugin</artifactId> <version>1.3.7</version> <configuration> <verbose>true</verbose> <overwrite>true</overwrite> </configuration> <dependencies> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>8.0.18</version> <scope>runtime</scope> </dependency> </dependencies> </plugin> </plugins> </build> </project> ``` generatorConfig.xml ``` <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE generatorConfiguration PUBLIC "-//mybatis.org//DTD MyBatis Generator Configuration 1.0//EN" "http://mybatis.org/dtd/mybatis-generator-config_1_0.dtd"> <generatorConfiguration> <!--导入配置文件--> <properties resource="application.properties"></properties> <!-- 一个数据库一个context --> <context id="default"> <!-- 注释生成设置 --> <commentGenerator> <!-- 是否生成注释代时间戳--> <property name="suppressDate" value="true" /> <!-- 是否取消注释 --> <property name="suppressAllComments" value="true" /> </commentGenerator> <!--jdbc的数据库连接--> <jdbcConnection driverClass="{spring.datasource.driver-class-name}" connectionURL="{spring.datasource.url}" userId="{spring.datasource.username}" password="{spring.datasource.password}"> <property name="nullCatalogMeansCurrent" value="true" /> </jdbcConnection> <!-- 类型转换 --> <javaTypeResolver> <!-- 是否使用bigDecimal, false可自动转化以下类型(Long, Integer, Short, etc.) --> <property name="forceBigDecimals" value="false" /> </javaTypeResolver> <!-- targetPackage:生成的实体类所在的包 --> <!-- targetProject:生成的实体类所在的硬盘位置 --> <javaModelGenerator targetPackage="com.example.demo.model" targetProject="src/main/java"> <!-- 是否允许子包 --> <property name="enableSubPackages" value="false" /> <!-- 是否对modal添加构造函数 --> <property name="constructorBased" value="true" /> <!-- 是否清理从数据库中查询出的字符串左右两边的空白字符 --> <property name="trimStrings" value="true" /> <!-- 建立modal对象是否不可改变 即生成的modal对象不会有setter方法,只有构造方法 --> <property name="immutable" value="false" /> </javaModelGenerator> <!-- targetPackage 和 targetProject:生成的 mapper xml 文件的包和位置 --> <sqlMapGenerator targetPackage="mapper" targetProject="src/main/resources"> <!-- 是否在当前路径下新加一层schema,ex:false路径com.qikegu.demo.model, com.qikegu.demo.model.[schemaName] --> <property name="enableSubPackages" value="false" /> <!-- 是否针对string类型的字段在set的时候进行trim调用 --> <property name="trimStrings" value="true"/> </sqlMapGenerator> <!-- targetPackage 和 targetProject:生成的 java interface 文件的包和位置 --> <javaClientGenerator type="XMLMAPPER" targetPackage="com.example.demo.repository" targetProject="src/main/java"> <!-- 是否在当前路径下新加一层schema,ex:false路径com.qikegu.demo.model, com.qikegu.demo.model.[schemaName] --> <property name="enableSubPackages" value="false" /> </javaClientGenerator> <!-- 配置表信息 --> <!-- schema即为数据库名 tableName为对应的数据库表 domainObjectName是要生成的实体类 enable*ByExample, 是否生成 example类 --> <!-- 不同的表,修改tableName和domainObjectName就可以 --> <table tableName="user" domainObjectName="User" enableCountByExample="false" enableUpdateByExample="false" enableDeleteByExample="false" enableSelectByExample="false" selectByExampleQueryId="false"> </table> </context> </generatorConfiguration> ```
有关于JPA和MybatisPlus的问题。
## 有关于 JPA 和 Mybatis Plus的问题 问题背景描述 1. 确定数据库字段和其所对应的实体类字段一致。例如:DB(mem_name),Class(memName) 2. 用于数据库操作的表,以下简称A表。A表中主键id,名称是id,类型varchar,不为NULL。 3. 我实体类定义如下: ``` // A就是A表对应的实体类 @Data @TableName("A") public class A extends BaseClass { ......... } @Data public abstract class BaseEntity { @TableId(value = "id") private String id ;//id在application.yml中是UUID的 ....... } ``` 问题: 1. 当使用 Mybatis Plus时: 1.1 利用SQL注解,BaseMapper.selectByID,通过Mapper.XML进行查询一行记录,在ServiceImpl的Test测试方法中可以查询出我需要的记录,而通过Controller进行调用Service方法来获取记录,但是SQL已经执行了。就无法查出,但是新增是可以向A表进行插入数据。 为什么通过Controller调用Service的方法,方面内部:selectByID或以上3中方式之一,就无法查询出数据. 2. 当使用 JPA 时: ``` // A就是A表对应的实体类 @Data @Entity @TableName("A") public class A extends BaseClass { @Id @TableId(value = "id") private String id ; ......... } @Data public abstract class BaseEntity { ....... } ``` 2.1 你看的没错,我就是把注解放到原有的MyBatis Plus上面,但是调整id位置了,我放到A类中,同样,可以测试查询,放到tomcat中,就无法用请求->controller->service->repository来查询所需数据? MyBatis-Plus:selectById()无法查询 JAP:findOne(id) 无法查询 都无法放到tomcat中,用请求的方式进行查询,测试都能过! 不明白。求赐教!
如何根据这个需求编写mysql,保证简洁和效率
我现在有两个表parent和child,根据parent.id等于child.parentId一对多关联。 child表有一字段status,取值 0或1或2。 现在我想要一起查询出每条parent的信息以及该条对应的child状态status分别为0、1、2的记录个数。 这个个数我不知道怎么取,比如下面是取parent信息和状态为0的child个数,但只能取到一种情况,不能同时取到三种状态的个数。 SELECT p. * , count ( * ) FROM parent p,child c WHERE c.parentid =p.id AND c.status= 0 GROUP BY c.parentid; 要同时取到三种状态就要继续加联表 SELECT * FROM (SELECT p. * , count ( * ) c1 ,p.ID aid FROM parent p,child c WHERE c.parentid =p.id AND c.STATUS = 0 GROUP BY c.parentid) a , (SELECT count ( * ) c2 ,p.ID bid FROM parent p,child c WHERE c.parentid =p.id AND c.STATUS = 1 GROUP BY c.parentid) b , (SELECT count ( * ) c3 ,p.ID cid FROM parent p,child c WHERE c.parentid =p.id AND c.STATUS = 2 GROUP BY c.parentid) c WHERE a.aid = b.bid AND c.cid = a.aid 这样sql会很长且低效。并且现在只有三个状态,要是多了更长,后面会写在mybatis的xml里很难看。有没有更好的写法?
mybatis 如何用update修改关联表Service业务层怎么实现
## /**软件环境**/ 框架:spring springMVC mybatis 数据库:mysql ## /**报错信息**/ ![图片说明](https://img-ask.csdn.net/upload/201903/04/1551665050_386888.png) ## /**代码提示**/ //数据层mybatis xml文件 ``` <?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="com.app.dao.mapper.MemberPermissionMapper"> <resultMap type="MemberPermission" id="MemberPermission"> <id column="id" property="id"/> <result column="member_id" property="member_id"/> <result column="ttys" property="ttys"/> <result column="key" property="key"/> <result column="lose_time" property="lose_time"/> <result column="note" property="note"/> <result column="update_time" property="update_time"/> <!-- 关联member表 --> <association property="member" javaType="com.app.bean.Member"> <id column="member_id" property="id"/> <result column="phone" property="phone"/> <result column="name" property="name"/> <result column="password" property="password"/> </association> </resultMap> <update id="updateMemberLoginPermission" parameterType="map"> UPDATE dt_member_permission AS t1 LEFT JOIN dt_member AS t2 ON t1.member_id=t2.id <set> <if test="key!=null and key !=''">t1.key=#{key}, </if> </set> WHERE t1.ttys=#{key} AND t2.phone=#{phone} AND t2.password=#{password} </update> ``` //service业务层接口实现类提示 phone和newpwd字段是在关联表member里面 ``` @Override public int updateMemberLoginPermission( String ttys, String phone, String newpwd, String key_dm) { MemberPermission memberPermission= new MemberPermission(); memberPermission.setTtys(ttys); memberPermission.setKey_dm(key_dm); Member member = new Member(); member.setPhone(phone); member.setPassword(newpwd); return memberPermissionDao.updateMemberLoginPermission(memberPermission,member); } ``` //javabean实体类提示 ``` package com.app.bean; import java.util.Date; /** * 用户权限组合表 * pjc * 2019.2.25 */ public class MemberPermission { private int id; private int member_id; private String ttys;//终端类型 private String key; private Date lose_time; private String note; private Date update_time; public MemberPermission() { } public MemberPermission(int id, int member_id, String ttys, String key, Date lose_time, String note, Date update_time) { this.id = id; this.member_id = member_id; this.ttys = ttys; this.key = key; this.lose_time = lose_time; this.note = note; this.update_time = update_time; } public int getId() { return id; } /**后面省略** ``` //关联表Javabean提示 ``` public class Member { private int id; private String name; private String password; private int gender; private Date birthday; private String phone; private String email; private Date regtime; private Date losetime; private Date losetime_jl; private Date losetime_tz; private Date losetime_bj; private Date losetime_sz; private String nickname; private String head; private int status; private int type; private String note; private String departments; private String hospital; private String province; private String city; private String country; private String key;//用户授权码实现单点登录 private String key_jl;//实现经络app单点登录 private String key_tz;//实现体质app单点登录 private String key_bj;//实现保健机构用户单点登录 private String key_sz;//实现手诊用户单点登录 private Date record_time; private String advice;//医师建议 ``` //mapper.java文件提示 ![图片说明](https://img-ask.csdn.net/upload/201903/04/1551686590_996340.png) ## /**尝试过的办法1: key字段已经统一改为key_dm和数据库实体类全部统一 去掉@param注解 修改mybatis.xml**/ //dao层接口代码提示 mapper.java文件 ``` public interface MemberPermissionMapper { public int updateMemberLoginPermission(MemberPermission memberPermission,Member member);//根据终端类型 用户手机号密码修改动态key 关联表 } ``` //service层接口提示 ``` package com.app.service; import java.util.Date; import java.util.List; import java.util.Map; import com.app.bean.Member; public interface MemberService { public int updateMemberLoginPermission(String ttys,String phone, String newpwd, String key_dm); } ``` //service层接口实现类提示 ``` @Override public int updateMemberLoginPermission( String ttys, String phone, String newpwd, String key_dm) { MemberPermission memberPermission= new MemberPermission(); memberPermission.setTtys(ttys); memberPermission.setKey_dm(key_dm); Member member = new Member(); member.setPhone(phone); member.setPassword(newpwd); return memberPermissionDao.updateMemberLoginPermission(memberPermission,member); } ``` //mybatis.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="com.app.dao.mapper.MemberPermissionMapper"> <resultMap type="com.app.bean.MemberPermission" id="MemberPermission"> <id column="id" property="id"/> <result column="member_id" property="member_id"/> <result column="ttys" property="ttys"/> <result column="key_dm" property="key_dm"/> <result column="lose_time" property="lose_time"/> <result column="note" property="note"/> <result column="update_time" property="update_time"/> <!-- 关联member表 --> <association property="member" javaType="com.app.bean.Member"> <id column="member_id" property="id"/> <result column="phone" property="phone"/> <result column="name" property="name"/> <result column="password" property="password"/> </association> </resultMap> <update id="updateMemberLoginPermission" parameterType="com.app.bean.Member"> UPDATE dt_member_permission AS t1 LEFT JOIN dt_member AS t2 ON t1.member_id=t2.id <set> <if test="key_dm!=null and key_dm !=''">t1.key_dm=#{key_dm}, </if> </set> WHERE t1.ttys=#{ttys} AND t2.phone=#{phone} AND t2.password=#{password} </update> ``` //报错提示 ![图片说明](https://img-ask.csdn.net/upload/201903/05/1551755075_567480.png) ## /**尝试方法2 已解决: 关联对象传参问题**/ 别用实体类传参,使用map。 Map map = new HashMap(); map.put("ttys",ttys); map.put("phone",phone); map.put("key_dm",key_dm); map.put("password",password); xml中的update语句修改成: UPDATE dt_member_permission AS t1 LEFT JOIN dt_member AS t2 ON t1.member_id=t2.id t1.key_dm=#{key_dm} WHERE t1.ttys=#{ttys} AND t2.phone=#{phone} AND t2.password=#{password}
变量time1,time2 在XML里以string方式入参找不到该字段
![![图片说明](https://img-ask.csdn.net/upload/201604/28/1461827430_235953.png)![![![图片说明](https://img-ask.csdn.net/upload/201604/28/1461827444_669002.png)![![图片说明](https://img-ask.csdn.net/upload/201604/28/1461827424_418275.png) 这参数的值是获取时间控件的值传进来的,我需要两个时间段的值来查,但是数据库只有一个时间reg date,不能跟数据库的字段对应啊。
column "" can not be null springmvc+mybatis
org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.springframework.dao.DataIntegrityViolationException: ### Error querying database. Cause: com.mysql.jdbc.exceptions.jdbc4.MySQLIntegrityConstraintViolationException: Column 'userName' cannot be null ### The error may exist in com/demo/dao/UserMapper.xml ### The error may involve com.demo.dao.UserMapper.insertUser-Inline ### The error occurred while setting parameters ### SQL: insert into user (userName,password,id) values (?,?,?) ### Cause: com.mysql.jdbc.exceptions.jdbc4.MySQLIntegrityConstraintViolationException: Column 'userName' cannot be null ; SQL []; Column 'userName' cannot be null; nested exception is com.mysql.jdbc.exceptions.jdbc4.MySQLIntegrityConstraintViolationException: Column 'userName' cannot be null org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:927) org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:811) javax.servlet.http.HttpServlet.service(HttpServlet.java:624) org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:796) javax.servlet.http.HttpServlet.service(HttpServlet.java:731) org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88) org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107 一直提示字段不能为空,这是因为没有接收到页面的请求参数吗?所以#{}接收不到值?怎样解决,求好心人搭救,感谢!
springboot 配置多库之后,mybatis在控制台不打印sql语句了
springboot项目 单库下,mybatis只需要添加如下配置,就可以打印sql语句 ```xml <!-- 打印查询语句 --> <setting name="logImpl" value="STDOUT_LOGGING" /> ``` 但是多库环境下,mybatis不论怎么设置,都无法打印sql语句..... ---- ---- 项目中的相关配置: mybatis配置: ```xml <!-- 设置运行参数 --> <settings> <!-- 全局映射器启用缓存 --> <setting name="cacheEnabled" value="true" /> <!-- 查询时,关闭关联对象及时加载以提高性能 --> <setting name="lazyLoadingEnabled" value="false" /> <!-- 设置关联对象加载的形态,此处为按需加载字段(加载字段由SQL指定),不会加载关联表的所有字段,以提高性能 --> <setting name="aggressiveLazyLoading" value="false" /> <!-- 对于位置的SQL查询,允许返回不同的结果集以达到通用的效果 --> <setting name="multipleResultSetsEnabled" value="true" /> <!-- 允许使用列标签代替列明 --> <setting name="useColumnLabel" value="true" /> <!-- 允许使用自定义的主键值(比如由程序生成的UUID 32位编码作为键值), 数据表的pk生成策略将被覆盖 --> <setting name="useGeneratedKeys" value="true" /> <!-- 给予被嵌套的resultMap以字段-属性的映射支持 --> <setting name="autoMappingBehavior" value="PARTIAL" /> <!-- 对于批量更新操作缓存SQL以提高性能 --> <setting name="defaultExecutorType" value="REUSE" /> <!-- 数据库超过25000秒仍未响应则超时 --> <!--<setting name="defaultStatementTimeout" value="25000" />--> <!-- 打印查询语句 --> <setting name="logImpl" value="STDOUT_LOGGING" /> <!-- 开启驼峰--> <setting name="mapUnderscoreToCamelCase" value="true" /> </settings> ``` logback配置: ```xml <?xml version="1.0" encoding="UTF-8"?> <configuration scan="true"> <!-- 属性1:每个logger都关联到logger上下文,默认上下文名称为“default”。 但可以使用设置成其他名字,用于区分不同应用程序的记录。一旦设置,不能修改,可以通过%contextName来打印日志上下文名称。 --> <contextName>logback</contextName> <!--属性2:定义日志文件的存储地址 勿在 LogBack 的配置中使用相对路径--> <!-- <springProfile name="dev"> <property name="LOG_PATH" value="D://care-management-statisticserver-logs"/> </springProfile> <springProfile name="test"> <property name="LOG_PATH" value="/data/tomcat_jar/taixin_care/care-management-statisticserver/logs"/> </springProfile> <springProfile name="prod"> <property name="LOG_PATH" value="/data1/logs/care-management-statisticserver"/> </springProfile> --> <property name="LOG_PATH" value="${LOG_FILE}"/> <!--appender用来格式化日志输出节点,有俩个属性name和class,class用来指定哪种输出策略,常用就是控制台输出策略和文件输出策略。--> <!-- %m输出的信息,%p日志级别,%t线程名,%d日期,%c类的全名,,,, --> <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender"> <filter class="ch.qos.logback.classic.filter.ThresholdFilter"> <level>info</level> </filter> <encoder> <pattern>%date %level [%thread] %logger{36} [%file : %line] %msg%n</pattern> </encoder> </appender> <!--<include resource="org/springframework/boot/logging/logback/base.xml"/>--> <!-- 说明: 1、日志级别及文件 日志记录采用分级记录,级别与日志文件名相对应,不同级别的日志信息记录到不同的日志文件中 例如:error级别记录到log_error_xxx.log或log_error.log(该文件为当前记录的日志文件),而log_error_xxx.log为归档日志, 日志文件按日期记录,同一天内,若日志文件大小等于或大于2M,则按0、1、2...顺序分别命名 例如log-level-2013-12-21.0.log 其它级别的日志也是如此。 2、文件路径 若开发、测试用,在Eclipse中运行项目,则到Eclipse的安装路径查找logs文件夹,以相对路径../logs。 若部署到Tomcat下,则在Tomcat下的logs文件中 3、Appender FILEERROR对应error级别,文件名以log-error-xxx.log形式命名 FILEWARN对应warn级别,文件名以log-warn-xxx.log形式命名 FILEINFO对应info级别,文件名以log-info-xxx.log形式命名 FILEDEBUG对应debug级别,文件名以log-debug-xxx.log形式命名 CONSOLE将日志信息输出到控制上,为方便开发测试使用 --> <!-- 日志记录器,日期滚动记录 --> <appender name="FILEERROR" class="ch.qos.logback.core.rolling.RollingFileAppender"> <!-- 正在记录的日志文件的路径及文件名 --> <file>${LOG_PATH}/error_statisticserver.log</file> <!-- 日志记录器的滚动策略,按日期,按大小记录 --> <rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy"> <!-- 归档的日志文件的路径,例如今天是2013-12-21日志,当前写的日志文件路径为file节点指定,可以将此文件与file指定文件路径设置为不同路径,从而将当前日志文件或归档日志文件置不同的目录。 而2013-12-21的日志文件在由fileNamePattern指定。%d{yyyy-MM-dd}指定日期格式,%i指定索引 --> <fileNamePattern>${LOG_PATH}/error-statisticserver-%d{yyyy-MM-dd}.%i.log</fileNamePattern> <!-- 表示只保留最近30天的日志,以防止日志填满整个磁盘空间。--> <maxHistory>30</maxHistory> <!--用来指定日志文件的上限大小,例如设置为1GB的话,那么到了这个值,就会删除旧的日志。--> <totalSizeCap>1GB</totalSizeCap> <!-- 除按日志记录之外,还配置了日志文件不能超过2M,若超过2M,日志文件会以索引0开始, 命名日志文件,例如log-error-2013-12-21.0.log --> <timeBasedFileNamingAndTriggeringPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP"> <maxFileSize>100MB</maxFileSize> </timeBasedFileNamingAndTriggeringPolicy> </rollingPolicy> <!-- 追加方式记录日志 --> <append>true</append> <!-- 日志文件的格式 --> <encoder class="ch.qos.logback.classic.encoder.PatternLayoutEncoder"> <pattern>%date %level [%thread] %logger{36} [%file : %line] %msg%n</pattern> <charset>utf-8</charset> </encoder> <!-- 此日志文件只记录error级别的 --> <filter class="ch.qos.logback.classic.filter.LevelFilter"> <level>ERROR</level> <onMatch>ACCEPT</onMatch> <onMismatch>DENY</onMismatch> </filter> </appender> <!-- 日志记录器,日期滚动记录 --> <appender name="FILEINFO" class="ch.qos.logback.core.rolling.RollingFileAppender"> <!-- 正在记录的日志文件的路径及文件名 --> <file>${LOG_PATH}/info_statisticserver.log</file> <!-- 日志记录器的滚动策略,按日期,按大小记录 --> <rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy"> <!-- 归档的日志文件的路径,例如今天是2013-12-21日志,当前写的日志文件路径为file节点指定,可以将此文件与file指定文件路径设置为不同路径,从而将当前日志文件或归档日志文件置不同的目录。 而2013-12-21的日志文件在由fileNamePattern指定。%d{yyyy-MM-dd}指定日期格式,%i指定索引 --> <fileNamePattern>${LOG_PATH}/info-statisticserver-%d{yyyy-MM-dd}.%i.log</fileNamePattern> <!-- 表示只保留最近30天的日志,以防止日志填满整个磁盘空间。--> <maxHistory>30</maxHistory> <!--用来指定日志文件的上限大小,例如设置为1GB的话,那么到了这个值,就会删除旧的日志。--> <totalSizeCap>1GB</totalSizeCap> <!-- 除按日志记录之外,还配置了日志文件不能超过2M,若超过2M,日志文件会以索引0开始,命名日志文件,例如log-error-2013-12-21.0.log --> <timeBasedFileNamingAndTriggeringPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP"> <maxFileSize>100MB</maxFileSize> </timeBasedFileNamingAndTriggeringPolicy> </rollingPolicy> <!-- 追加方式记录日志 --> <append>true</append> <!-- 日志文件的格式 --> <encoder class="ch.qos.logback.classic.encoder.PatternLayoutEncoder"> <pattern>%date %level [%thread] %logger{36} [%file : %line] %msg%n</pattern> <charset>utf-8</charset> </encoder> <!-- 此日志文件只记录info级别的 --> <filter class="ch.qos.logback.classic.filter.LevelFilter"> <level>INFO</level> <onMatch>ACCEPT</onMatch> <onMismatch>DENY</onMismatch> </filter> </appender> <!-- <logger>用来设置某一个包或者具体的某一个类的日志打印级别、以及指定<appender>。<logger>仅有一个name属性,一个可选的level和一个可选的addtivity属性。 --> <logger name="org.springframework" level="INFO"/> <logger name="org.apache" level="ERROR"/> <logger name="org.hibernate.validator" level="ERROR"/> <!--<logger name="org.thymeleaf" level="ERROR"/>--> <logger name="org.springframework.context.annotation" level="ERROR"/> <!-- springProfile多环境日志输出,据不同环境(prod:生产环境,test:测试环境,dev:开发环境)来定义不同的日志输出--> <springProfile name="dev" /> <root level="INFO"> <appender-ref ref="FILEERROR"/> <appender-ref ref="FILEINFO"/> <appender-ref ref="STDOUT"/> </root> <!-- 可以启动服务的时候指定 profile (如不指定使用默认),如指定prod 的方式为: java -jar xxx.jar –spring.profiles.active=prod--> </configuration> ``` application.properties部分配置: ```properties #配置文件 logging.level.tk.mybatis=TRACE spring.freemarker.cache=false spring.freemarker.request-context-attribute=request mybatis.type-aliases-package=com.mtpf.domain mybatis.mapper-locations=classpath:mapper/*.xml mapper.mappers=com.mtpf.util.MyMapper mapper.not-empty=false mapper.identity=MYSQL pagehelper.helperDialect=mysql #true 是超出最大页码返回数据 false超出最大页码不返回数据 pagehelper.reasonable=${PAGEHELPER_REASONABLE} pagehelper.supportMethodsArguments=true pagehelper.params=count=countSql ```
任意字段的模糊查询怎么设置参数?
## 1.请问field1和field2这两个字段应该怎么设置? ``` <?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="com.mustang.mapper.SpecilMapper"> <resultMap id="myMap" type="com.mustang.po.Specil"> <id property="sid" column="spilinfoid"/> <result property="did" column="depinfoid"/> <result property="sCode" column="spilinfocode"/> <result property="sName" column="spilinfoname"/> <result property="sAim" column="spilinfoaim"/> <result property="sProdire" column="spilinfoprodire"/> </resultMap> <select id="queryLikeAndPageAndSort" parameterType="java.util.Map" resultMap="myMap" > SELECT * from specilinfo where spilinfoname like concat('%',#{value},'%') ORDER BY spilinfoid DESC limit #{start},#{pageSize} </select> </mapper> ``` ## 报错: ![图片说明](https://img-ask.csdn.net/upload/201904/18/1555553621_115985.png) ## 将field1和field修改为具体的字段名后 ``` <select id="queryLikeAndPageAndSort" parameterType="java.util.Map" resultMap="myMap" > SELECT * from specilinfo where spilinfoname like concat('%',#{value},'%') ORDER BY spilinfoid DESC limit #{start},#{pageSize} </select> ``` ## 结果如下: ![图片说明](https://img-ask.csdn.net/upload/201904/18/1555553725_71584.png) ## 测试类: ![图片说明](https://img-ask.csdn.net/upload/201904/18/1555553743_941748.png)
Spring mvc 中的mapper.xml的SQL语句报错
### Error updating database. Cause: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'interval=2,conn_timeout=1,resp_timeout=1,test_retry=1,freq=2,monit_conn_timeout=' at line 1 ### The error may involve com.security.dao.TemplateNetworkDao.updateTempNetwork-Inline ### The error occurred while setting parameters ### SQL: update conf_template_network set interval=?,conn_timeout=?,resp_timeout=?,test_retry=?,freq=?,monit_conn_timeout=?,monit_resp_timeout=?,monit_retry=? where id=? ### Cause: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'interval=2,conn_timeout=1,resp_timeout=1,test_retry=1,freq=2,monit_conn_timeout=' at line 1 ; bad SQL grammar []; nested exception is com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'interval=2,conn_timeout=1,resp_timeout=1,test_retry=1,freq=2,monit_conn_timeout=' at line 1_ 我的SQL语句是 ``` <update id="updateTempNetwork" parameterType="int"> update conf_template_network set interval=#{interval},conn_timeout=#{conn_timeout},resp_timeout=#{resp_timeout},test_retry=#{test_retry},freq=#{freq},monit_conn_timeout=#{monit_conn_timeout},monit_resp_timeout=#{monit_resp_timeout},monit_retry=#{monit_retry} where id=#{id} </update> ``` 找了半天也没找到哪写错了,而且也没有使用mysql的关键字,提示说monit_conn_timeout附近的错误 # ## ——————————————————————————————————** # ## 更新:好像是SQL语句太长了,把前边的字段改短后,前边的字段就能正确显示,但是后边超出长度的部分还是会报错 我把前边长的字段用a,b替代之后,变短了: ``` <update id="updateTempNetwork" parameterType="com.security.entity.TemplateNetwork"> update conf_template_network set interval=#{interval},conn_timeout=#{conn_timeout},resp_timeout=#{resp_timeout},test_retry=#{test_retry},freq=#{freq},a=#{a},b=#{b},monit_retry=#{monit_retry} where id=#{id} </update> ``` 错误就移到了后边: Cause: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'interval=3,conn_timeout=3,resp_timeout=3,test_retry=3,freq=1,a=2,b=1,monit_retry' at line 1 ; bad SQL grammar []; nested exception is com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'interval=3,conn_timeout=3,resp_timeout=3,test_retry=3,freq=1,a=2,b=1,monit_retry' at line 1 好像跟长度又没关系 把后边的字段都砍掉了之后 ``` <update id="updateTempNetwork" parameterType="com.security.entity.TemplateNetwork"> update conf_template_network set interval=#{interval},conn_timeout=#{conn_timeout},resp_timeout=#{resp_timeout},test_retry=#{test_retry},freq=#{freq} where id=#{id} </update> ``` 还是会报错: 移到了最后: ### SQL: update conf_template_network set interval=?,conn_timeout=?,resp_timeout=?,test_retry=?,freq=? where id=? ### Cause: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'interval=1,conn_timeout=2,resp_timeout=2,test_retry=1,freq=1 where id=1' at line 1 ; bad SQL grammar []; nested exception is com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'interval=1,conn_timeout=2,resp_timeout=2,test_retry=1,freq=1 where id=1' at line 1 at org.springframework.jdbc.support.SQLErrorCodeSQLExceptionTranslator.doTranslate(SQLErrorCodeSQLExceptionTranslator.java:231) at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:73) at org.mybatis.spring.MyBatisExceptionTranslator.translateExceptionIfPossible(MyBatisExceptionTranslator.java:73) at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:446) at $Proxy29.update(Unknown Source) at org.mybatis.spring.SqlSessionTemplate.update(SqlSessionTemplate.java:294) at org.apache.ibatis.binding.MapperMethod.execute(MapperMethod.java:62) at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:59) at $Proxy37.updateTempNetwork(Unknown Source) at com.security.service.impl.TemplateNetworkImpl.updateTempNetwork(TemplateNetworkImpl.java:35) at com.security.service.impl.TemplateNetworkImpl$$FastClassBySpringCGLIB$$16455d80.invoke(<generated>) at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204) at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:738) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:157) at org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:99) at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:282) at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:96) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:92) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:673) at com.security.service.impl.TemplateNetworkImpl$$EnhancerBySpringCGLIB$$a87fea1.updateTempNetwork(<generated>) at com.security.controller.TemplateNetworkController.updateTempNetwork(TemplateNetworkController.java:47) 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.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:205) at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:133) at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:97) at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:827) at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:738) at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85) at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:967) at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:901) at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970) at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:872) at javax.servlet.http.HttpServlet.service(HttpServlet.java:646) at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846) at javax.servlet.http.HttpServlet.service(HttpServlet.java:727) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:197) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) at org.apache.shiro.web.servlet.AbstractShiroFilter.executeChain(AbstractShiroFilter.java:449) at org.apache.shiro.web.servlet.AbstractShiroFilter$1.call(AbstractShiroFilter.java:365) at org.apache.shiro.subject.support.SubjectCallable.doCall(SubjectCallable.java:90) at org.apache.shiro.subject.support.SubjectCallable.call(SubjectCallable.java:83) at org.apache.shiro.subject.support.DelegatingSubject.execute(DelegatingSubject.java:383) at org.apache.shiro.web.servlet.AbstractShiroFilter.doFilterInternal(AbstractShiroFilter.java:362) at org.apache.shiro.web.servlet.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:125) at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:346) at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:262) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) at org.apache.logging.log4j.web.Log4jServletFilter.doFilter(Log4jServletFilter.java:71) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:501) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103) at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408) at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1070) at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:611) at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:316) at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) at java.lang.Thread.run(Unknown Source) Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'interval=1,conn_timeout=2,resp_timeout=2,test_retry=1,freq=1 where id=1' at line 1 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:408) at com.mysql.jdbc.Util.getInstance(Util.java:383) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1062) at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4226) at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4158) at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2615) at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2776) at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2840) at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:2082) at com.mysql.jdbc.PreparedStatement.execute(PreparedStatement.java:1302) at com.mchange.v2.c3p0.impl.NewProxyPreparedStatement.execute(NewProxyPreparedStatement.java:67) 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.logging.jdbc.PreparedStatementLogger.invoke(PreparedStatementLogger.java:59) at $Proxy48.execute(Unknown Source) at org.apache.ibatis.executor.statement.PreparedStatementHandler.update(PreparedStatementHandler.java:46) at org.apache.ibatis.executor.statement.RoutingStatementHandler.update(RoutingStatementHandler.java:74) at org.apache.ibatis.executor.SimpleExecutor.doUpdate(SimpleExecutor.java:50) at org.apache.ibatis.executor.BaseExecutor.update(BaseExecutor.java:117) at org.apache.ibatis.executor.CachingExecutor.update(CachingExecutor.java:76) at org.apache.ibatis.session.defaults.DefaultSqlSession.update(DefaultSqlSession.java:198) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) at java.lang.reflect.Method.invoke(Unknown Source) at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:433) # ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ # 结贴啦结帖啦! # 休息两天果然脑细胞就活过来了,周一一大早就找到了bug # interval是mySQL的关键字,用作变量名,所以报错了,换个名字就好了。已经是第二次撞到关键字了,以后起变量名要小心了。 # 非常感谢各位的帮助!!
关于mybatis延迟加载的问题
我做了一个mybatis的demo里面有两个类:user address,user中存放着一个address,而在数据库中user表中有一个addressid的字段,用于关联address表。 public class User { private int id; private String name; private String password; private int age; private Address address; //get set方法 } public class Address { private int addid; private String addname; private int zipcode; //get set方法 } mybatis配置文件 <configuration> <!-- 延迟加载设置 --> <settings> <setting name="lazyLoadingEnabled" value="true"/> </settings> <!-- 别名 --> <typeAliases> <typeAlias type="com.qshun.model.User" alias="user"/> <typeAlias type="com.qshun.model.Address" alias="address"/> </typeAliases> <!-- 环境参数(数据库连接) --> <environments default="development"> <environment id="development"> <transactionManager type="JDBC" /> <dataSource type="POOLED"> <property name="driver" value="com.mysql.jdbc.Driver" /> <property name="url" value="jdbc:mysql://localhost/ibatis" /> <property name="username" value="root" /> <property name="password" value="root" /> </dataSource> </environment> </environments> <!-- 映射文件 --> <mappers> <mapper resource="com/qshun/model/AddressMapper.xml"/> <mapper resource="com/qshun/model/UserMapper.xml"/> </mappers> </configuration> usermapper的实体映射文件 <mapper namespace="com.qshun.mapper.UserMapper"> <resultMap type="user" id="UserResultMap"> <result property="id" column="uid" /> <result property="name" column="uname" /> <result property="password" column="upassword" /> <result property="age" column="uage" /> <association property="address" column="addressid" select="getAddressById" resultMap="AddressResultMap"> </association> </resultMap> <resultMap id="AddressResultMap" type="address"> <result property="addid" column="id"/> <result property="addname" column="addressname"/> <result property="zipcode" column="zipcode"/> </resultMap> <select id="getUserById" resultMap="UserResultMap" parameterType="int"> select uid,uname,upassword,uage,addressid from user where uid=#{id} </select> <select id="getAddressById" resultMap="AddressResultMap"> select addid, addname, zipcode from addr where addid =#{addressid} </select> </mapper> 测试类 private static SqlSession session = null; private static SqlSessionFactory sqlSessionFactory = null; static { try { Reader reader = Resources.getResourceAsReader("MybatisConfig.xml"); sqlSessionFactory = new SqlSessionFactoryBuilder().build(reader); session = sqlSessionFactory.openSession(true); reader.close(); } catch (IOException e) { throw new RuntimeException("=========" + e, e); } } public static void main(String[] args) { UserMapper mapper=session.getMapper(UserMapper.class); User u=mapper.getUserById(1);//理论上讲在执行此操作的时候,不会将address对象查询出来 System.out.println(u.getName()); System.out.println("================"); System.out.println(u.getAddress().getAddname());//此时address才会被执行查询 //但是事实上在执行mapper.getUserById(1)的时候,就执行了address对象的查询,延迟加载没有起效 session.close(); } 另附建表语句 CREATE TABLE `ibatis`.`add` ( `addid` INTEGER UNSIGNED NOT NULL AUTO_INCREMENT, `addname` VARCHAR(45), `zipcode` VARCHAR(45), PRIMARY KEY (`addid`) ) ENGINE = InnoDB; CREATE TABLE `ibatis`.`user` ( `uid` INTEGER UNSIGNED NOT NULL AUTO_INCREMENT, `uname` VARCHAR(45), `upassword` VARCHAR(45), `uage` VARCHAR(45), `addressid` VARCHAR(45), PRIMARY KEY (`uid`) ) ENGINE = InnoDB; 请各位牛人,帮忙解答一下,不胜感激 :D
org.apache.ibatis.exceptions.PersistenceException怎么解决?
调试一个开源项目出现报错,项目所有sql都会报空指针异常 ``` 严重: Servlet.service() for servlet [springMvc] in context with path [/mallapp] threw exception [Request processing failed; nested exception is org.mybatis.spring.MyBatisSystemException: nested exception is org.apache.ibatis.exceptions.PersistenceException: ### Error querying database. Cause: java.lang.NullPointerException ### The error may exist in file [H:\WorksSpace\.metadata\.plugins\org.eclipse.wst.server.core\tmp2\wtpwebapps\mallapp\WEB-INF\classes\mybatis\category\CategoryMapper.xml] ### The error may involve CategoryMapper.listAll-Inline ### The error occurred while setting parameters ### SQL: select category_name, category_img, sort, category_id, super_id from shop_category where super_id =? order by sort ### Cause: java.lang.NullPointerException] with root cause java.lang.NullPointerException at org.apache.ibatis.type.BaseTypeHandler.setParameter(BaseTypeHandler.java:43) at org.apache.ibatis.scripting.defaults.DefaultParameterHandler.setParameters(DefaultParameterHandler.java:81) at org.apache.ibatis.executor.statement.PreparedStatementHandler.parameterize(PreparedStatementHandler.java:80) at org.apache.ibatis.executor.statement.RoutingStatementHandler.parameterize(RoutingStatementHandler.java:61) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:606) at org.apache.ibatis.plugin.Plugin.invoke(Plugin.java:62) at com.sun.proxy.$Proxy84.parameterize(Unknown Source) at org.apache.ibatis.executor.ReuseExecutor.prepareStatement(ReuseExecutor.java:79) at org.apache.ibatis.executor.ReuseExecutor.doQuery(ReuseExecutor.java:56) at org.apache.ibatis.executor.BaseExecutor.queryFromDatabase(BaseExecutor.java:267) at org.apache.ibatis.executor.BaseExecutor.query(BaseExecutor.java:137) at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:96) at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:77) at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:108) at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:102) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:606) at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:358) at com.sun.proxy.$Proxy74.selectList(Unknown Source) at org.mybatis.spring.SqlSessionTemplate.selectList(SqlSessionTemplate.java:198) at com.yq.dao.DaoSupport.findForList(DaoSupport.java:118) at com.yq.service.category.impl.CategoryService.listAll(CategoryService.java:62) at com.yq.service.category.impl.CategoryService$$FastClassBySpringCGLIB$$51d95cd7.invoke(<generated>) at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204) at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:711) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:157) at org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:98) at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:262) at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:95) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:92) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:644) at com.yq.service.category.impl.CategoryService$$EnhancerBySpringCGLIB$$c2253a36.listAll(<generated>) at com.yq.controller.category.CategoryController.list(CategoryController.java:80) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:606) at org.springframework.web.method.support.InvocableHandlerMethod.invoke(InvocableHandlerMethod.java:215) at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:132) at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:104) at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:749) at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:690) at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:83) at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:945) at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:876) at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:961) at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:852) at javax.servlet.http.HttpServlet.service(HttpServlet.java:624) at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:837) at javax.servlet.http.HttpServlet.service(HttpServlet.java:731) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) at com.alibaba.druid.support.http.WebStatFilter.doFilter(WebStatFilter.java:123) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:108) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:505) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:169) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103) at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:956) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:436) at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1078) at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:625) at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:316) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) at java.lang.Thread.run(Thread.java:745) ``` CategoryMapper.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="CategoryMapper"> <!--表名 --> <sql id="tableName"> shop_category </sql> <!-- 字段 --> <sql id="Field"> category_name, category_img, sort, category_id, super_id </sql> <!-- 字段值 --> <sql id="FieldValue"> #{category_name}, #{category_img}, #{sort}, #{category_id}, #{super_id} </sql> <!-- 新增--> <insert id="save" parameterType="pd"> insert into <include refid="tableName"></include> ( <include refid="Field"></include> ) values ( <include refid="FieldValue"></include> ) </insert> <!-- 删除--> <delete id="delete" parameterType="pd"> delete from <include refid="tableName"></include> where category_id = #{category_id} </delete> <!-- 修改 --> <update id="edit" parameterType="pd"> update <include refid="tableName"></include> set category_name = #{category_name}, category_img = #{category_img}, sort = #{sort} where category_id = #{category_id} </update> <!-- 通过ID获取数据 --> <select id="findById" parameterType="pd" resultType="pd"> select <include refid="Field"></include> from <include refid="tableName"></include> where category_id = #{category_id} </select> <!-- 列表 --> <select id="datalistPage" parameterType="page" resultType="pd"> select <include refid="Field"></include> from <include refid="tableName"></include> where 1=1 and super_id =#{pd.super_id} order by sort </select> <!-- 列表(全部) --> <select id="listAll" parameterType="pd" resultType="pd"> select <include refid="Field"></include> from <include refid="tableName"></include> where super_id =#{super_id} order by sort </select> <!-- 批量删除 --> <delete id="deleteAll" parameterType="String"> delete from <include refid="tableName"></include> where category_id in <foreach item="item" index="index" collection="array" open="(" separator="," close=")"> #{item} </foreach> </delete> </mapper> ``` mybatis-config.xml ``` <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD SQL Map Config 3.0//EN" "http://mybatis.org/dtd/mybatis-3-config.dtd"> <configuration> <settings> <setting name="cacheEnabled" value="true" /><!-- 全局映射器启用缓存 --> <setting name="useGeneratedKeys" value="true" /> <setting name="defaultExecutorType" value="REUSE" /> <!-- 打印查询语句 --> <setting name="logImpl" value="LOG4J" /> </settings> <typeAliases> <typeAlias type="org.change.entity.system.User" alias="User"/> <typeAlias type="org.change.entity.system.Role" alias="Role"/> <typeAlias type="org.change.entity.system.Menu" alias="Menu"/> <typeAlias type="org.change.entity.system.Dictionaries" alias="Dictionaries"/> <typeAlias type="org.change.entity.system.Department" alias="Department"/> <typeAlias type="org.change.util.PageData" alias="pd"/> <!-- 分页 --> <typeAlias type="org.change.entity.Page" alias="Page"/> </typeAliases> <plugins> <plugin interceptor="org.change.plugin.PagePlugin"> <property name="dialect" value="mysql"/> <property name="pageSqlId" value=".*listPage.*"/> </plugin> </plugins> </configuration> ``` DAO.java ``` public interface DAO { /** * 保存对象 * @param str * @param obj * @return * @throws Exception */ public Object save(String str, Object obj) throws Exception; /** * 修改对象 * @param str * @param obj * @return * @throws Exception */ public Object update(String str, Object obj) throws Exception; /** * 删除对象 * @param str * @param obj * @return * @throws Exception */ public Object delete(String str, Object obj) throws Exception; /** * 查找对象 * @param str * @param obj * @return * @throws Exception */ public Object findForObject(String str, Object obj) throws Exception; /** * 查找对象 * @param str * @param obj * @return * @throws Exception */ public Object findForList(String str, Object obj) throws Exception; /** * 查找对象封装成Map * @param s * @param obj * @return * @throws Exception */ public Object findForMap(String sql, Object obj, String key , String value) throws Exception; } ``` DaoSupport.java ``` @Repository("daoSupport") public class DaoSupport implements DAO { @Resource(name = "sqlSessionTemplate") private SqlSessionTemplate sqlSessionTemplate; /** * 保存对象 * @param str * @param obj * @return * @throws Exception */ public Object save(String str, Object obj) throws Exception { return sqlSessionTemplate.insert(str, obj); } /** * 批量更新 * @param str * @param obj * @return * @throws Exception */ public Object batchSave(String str, List objs )throws Exception{ return sqlSessionTemplate.insert(str, objs); } /** * 修改对象 * 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Exception { return sqlSessionTemplate.delete(str, obj); } /** * 查找对象 * @param str * @param obj * @return * @throws Exception */ public Object findForObject(String str, Object obj) throws Exception { return sqlSessionTemplate.selectOne(str, obj); } /** * 查找对象 * @param str * @param obj * @return * @throws Exception */ public Object findForList(String str, Object obj) throws Exception { return sqlSessionTemplate.selectList(str, obj); } public Object findForMap(String str, Object obj, String key, String value) throws Exception { return sqlSessionTemplate.selectMap(str, obj, key); } } ``` 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:context="http://www.springframework.org/schema/context" xmlns:tx="http://www.springframework.org/schema/tx" xsi:schemaLocation="http://www.springframework.org/schema/beans 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name="username" value="${username}" /> <property name="password" value="${password}" /> <property name="filters" value="${filters}" /> <!-- 最大并发连接数 --> <property name="maxActive" value="${maxActive}" /> <!-- 初始化连接数量 --> <property name="initialSize" value="${initialSize}" /> <!-- 配置获取连接等待超时的时间 --> <property name="maxWait" value="${maxWait}" /> <!-- 最小空闲连接数 --> <property name="minIdle" value="${minIdle}" /> <!-- 配置间隔多久才进行一次检测,检测需要关闭的空闲连接,单位是毫秒 --> <property name="timeBetweenEvictionRunsMillis" value="${timeBetweenEvictionRunsMillis}" /> <!-- 配置一个连接在池中最小生存的时间,单位是毫秒 --> <property name="minEvictableIdleTimeMillis" value="${minEvictableIdleTimeMillis}" /> <property name="validationQuery" value="${validationQuery}" /> <property name="testWhileIdle" value="${testWhileIdle}" /> <property name="testOnBorrow" value="${testOnBorrow}" /> <property name="testOnReturn" value="${testOnReturn}" /> <property name="maxOpenPreparedStatements" value="${maxOpenPreparedStatements}" /> <!-- 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read-only="false" rollback-for="java.lang.Exception" /> <tx:method name="save*" propagation="REQUIRED" read-only="false" rollback-for="java.lang.Exception" /> <tx:method name="*" propagation="SUPPORTS"/> </tx:attributes> </tx:advice> <aop:aspectj-autoproxy proxy-target-class="true"/> <!-- 事物处理 --> <aop:config> <aop:pointcut id="pc" expression="execution(* com.*.service..*(..))" /> <aop:advisor pointcut-ref="pc" advice-ref="txAdvice" /> </aop:config> <!-- 配置mybatis --> <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean"> <property name="dataSource" ref="dataSource" /> <property name="configLocation" value="classpath:mybatis-config.xml"></property> <!-- mapper扫描 --> <property name="mapperLocations" value="classpath:mybatis/*/*.xml"></property> </bean> <bean id="sqlSessionTemplate" class="org.mybatis.spring.SqlSessionTemplate"> <constructor-arg ref="sqlSessionFactory" /> </bean> </beans> ```
mybatisplus自动生成的代码为什么导入的包路径错误?
## 第一次使用Mybatis-plus,在做完配置之后,点击mp:code,生成的代码如下: 很多文件中都是包的路径错误,这是什么情况啊,。。。。应该怎么解决呢??? 这里是包的路径import com.baomidou.mybatisplus.annotation.TableId; 生成的是import com.baomidou.mybatisplus.annotations.TableId; ![图片说明](https://img-ask.csdn.net/upload/201811/30/1543546984_436119.png) 这里路径应该为import com.baomidou.mybatisplus.extension.service.IService; 结果生成了import com.baomidou.framework.service.IService; ![图片说明](https://img-ask.csdn.net/upload/201811/30/1543547119_100572.png) 配置文件如下: 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>com.wuyunfeng</groupId> <artifactId>TestPlus</artifactId> <version>1.0-SNAPSHOT</version> <packaging>war</packaging> <name>TestPlus Maven Webapp</name> <url>http://www.wuyunfeng.com</url> <properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding> <maven.compiler.source>1.7</maven.compiler.source> <maven.compiler.target>1.7</maven.compiler.target> <!-- spring版本号 --> <spring.version>4.3.5.RELEASE</spring.version> <!-- mybatis版本号 --> <mybatis.version>3.4.1</mybatis.version> <!-- log4j日志文件管理包版本 --> <slf4j.version>1.7.12</slf4j.version> <log4j.version>1.2.17</log4j.version> </properties> <dependencies> <!-- 单元测试 --> <dependency> <groupId>junit</groupId> <artifactId>junit</artifactId> <version>4.11</version> <!-- 表示开发的时候引入,发布的时候不会加载此包 --> <scope>test</scope> </dependency> <!-- java ee包 --> <dependency> <groupId>javax</groupId> <artifactId>javaee-api</artifactId> <version>7.0</version> </dependency> <!-- 导入mybatis-plus包 start --> <dependency> <groupId>com.baomidou</groupId> <artifactId>mybatis-plus</artifactId> <version>3.0.6</version> </dependency> <dependency> <groupId>org.apache.velocity</groupId> <artifactId>velocity</artifactId> <version>1.7</version> </dependency> <!-- 导入mybatis-plus包 end --> <!-- 数据库驱动 --> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>5.1.41</version> </dependency> <!-- 导入dbcp的jar包,用来在applicationContext.xml中配置数据库 --> <dependency> <groupId>commons-dbcp</groupId> <artifactId>commons-dbcp</artifactId> <version>1.4</version> </dependency> <!-- jstl标签类 --> <dependency> <groupId>jstl</groupId> <artifactId>jstl</artifactId> <version>1.2</version> </dependency> <dependency> <groupId>taglibs</groupId> <artifactId>standard</artifactId> <version>1.1.2</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>${slf4j.version}</version> </dependency> <!-- log END --> <!-- 格式化对象,方便输出日志 --> <dependency> <groupId>com.alibaba</groupId> <artifactId>fastjson</artifactId> <version>1.2.6</version> </dependency> <dependency> <groupId>org.codehaus.jackson</groupId> <artifactId>jackson-mapper-asl</artifactId> <version>1.9.13</version> </dependency> <!-- 上传组件包 start --> <dependency> <groupId>commons-fileupload</groupId> <artifactId>commons-fileupload</artifactId> <version>1.3.1</version> </dependency> <dependency> <groupId>commons-io</groupId> <artifactId>commons-io</artifactId> <version>2.4</version> </dependency> <dependency> <groupId>commons-codec</groupId> <artifactId>commons-codec</artifactId> <version>1.10</version> </dependency> <!-- 上传组件包 end --> <!-- AL相关添加 --> <dependency> <groupId>net.sourceforge.jexcelapi</groupId> <artifactId>jxl</artifactId> <version>2.6</version> </dependency> <dependency> <groupId>org.apache.poi</groupId> <artifactId>poi</artifactId> <version>3.8</version> </dependency> <dependency> <groupId>org.apache.poi</groupId> <artifactId>poi-ooxml</artifactId> <version>3.9</version> </dependency> <!-- AL相关添加 --> <!-- https://mvnrepository.com/artifact/net.sourceforge.javacsv/javacsv --> <dependency> <groupId>net.sourceforge.javacsv</groupId> <artifactId>javacsv</artifactId> <version>2.0</version> </dependency> <!-- spring框架包 start --> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-core</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-web</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-tx</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-jdbc</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-test</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-aop</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-oxm</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-context-support</artifactId> <version>${spring.version}</version> </dependency> <!-- spring框架包 end --> <!-- spring 新添加的可选包 项目中未用到--> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-context</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-expression</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-orm</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-aspects</artifactId> <version>${spring.version}</version> </dependency> </dependencies> <build> <finalName>TestPlus</finalName> <plugins> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-compiler-plugin</artifactId> <version>2.3.2</version> <configuration> <source>1.6</source> <target>1.6</target> </configuration> </plugin> <plugin> <groupId>com.baomidou</groupId> <artifactId>mybatisplus-maven-plugin</artifactId> <version>1.0</version> <configuration> <!-- 输出目录(默认java.io.tmpdir) --> <outputDir>/run/media/ry03/wuyunfeng/workspace/IDEA/TestPlus/src/main/java</outputDir> <!-- 是否覆盖同名文件(默认false) --> <fileOverride>true</fileOverride> <!-- mapper.xml 中添加二级缓存配置(默认true) --> <enableCache>false</enableCache> <!-- 开发者名称 --> <author>WuYunfeng</author> <!-- 是否开启 ActiveRecord 模式(默认true) --> <activeRecord>false</activeRecord> <!-- 数据源配置,( **必配** ) --> <dataSource> <driverName>com.mysql.jdbc.Driver</driverName> <url>jdbc:mysql://127.0.0.1:3306/testssm?useUnicode=true&amp;useSSL=false&amp;characterEncoding=utf-8</url> <username>root</username> <password>123456</password> </dataSource> <strategy> <!-- 字段生成策略,四种类型,从名称就能看出来含义: nochange(默认), underline_to_camel,(下划线转驼峰) remove_prefix,(去除第一个下划线的前部分,后面保持不变) remove_prefix_and_camel(去除第一个下划线的前部分,后面转驼峰) --> <naming>underline_to_camel</naming> <!-- 表前缀 --> <tablePrefix>bmd_</tablePrefix> <!--Entity中的ID生成策略(默认 id_worker)--> <idGenType>auto</idGenType> <!--自定义超类--> <!--<superServiceClass>com.baomidou.base.BaseService</superServiceClass>--> <!-- 要包含的表 与exclude 二选一配置--> <include> <property>user</property> <!--<property>message</property>--> </include> <!-- 要排除的表 --> <!--<exclude>--> <!--<property>schema_version</property>--> <!--</exclude>--> </strategy> <packageInfo> <!-- 父级包名称,如果不写,下面的service等就需要写全包名(默认com.baomidou) --> <parent>com.wuyunfeng</parent> <!-- service包名(默认service) --> <service>service</service> <!-- serviceImpl包名(默认service.impl) --> <serviceImpl>service.impl</serviceImpl> <!-- entity包名(默认entity) --> <entity>model</entity> <!-- mapper包名(默认mapper) --> <mapper>mapper</mapper> <!-- xml包名(默认mapper.xml) --> <xml>mapper.xml</xml> <!-- controller包名(默认controller) --> <controller>controller</controller> </packageInfo> </configuration> <dependencies> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>5.1.41</version> </dependency> </dependencies> </plugin> </plugins> </build> </project> ```
相见恨晚的超实用网站
相见恨晚的超实用网站 持续更新中。。。
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