chunyublog 2024-06-03 17:42 采纳率: 0%
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HTTP Status 500 -

HTTP Status 500 -
type Exception report

message

description The server encountered an internal error that prevented it from fulfilling this request.

exception

org.apache.ibatis.exceptions.PersistenceException:

Error querying database. Cause: com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to database server.

The error may exist in com/cxy/mapper/BrandMapper.java (best guess)

The error may involve com.cxy.mapper.BrandMapper.selectAll

The error occurred while executing a query

Cause: com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to database server.

org.apache.ibatis.exceptions.ExceptionFactory.wrapException(ExceptionFactory.java:30)
org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:149)
org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:140)
org.apache.ibatis.binding.MapperMethod.executeForMany(MapperMethod.java:147)
org.apache.ibatis.binding.MapperMethod.execute(MapperMethod.java:80)
org.apache.ibatis.binding.MapperProxy$PlainMethodInvoker.invoke(MapperProxy.java:152)
org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:85)
jdk.proxy4/jdk.proxy4.$Proxy30.selectAll(Unknown Source)
com.cxy.service.impl.BrandServiceImpl.selectAll(BrandServiceImpl.java:22)
com.cxy.web.servlet.SelectAllServlet.doGet(SelectAllServlet.java:21)
javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:51)

root cause

com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to database server.
java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:77)
java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:499)
java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:480)
com.mysql.jdbc.Util.handleNewInstance(Util.java:377)
com.mysql.jdbc.Util.getInstance(Util.java:360)
com.mysql.jdbc.SQLError.createSQLException(SQLError.java:956)
com.mysql.jdbc.SQLError.createSQLException(SQLError.java:935)
com.mysql.jdbc.SQLError.createSQLException(SQLError.java:924)
com.mysql.jdbc.SQLError.createSQLException(SQLError.java:870)
com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2311)
com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2064)
com.mysql.jdbc.ConnectionImpl.(ConnectionImpl.java:790)
com.mysql.jdbc.JDBC4Connection.(JDBC4Connection.java:44)
java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:77)
java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:499)
java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:480)
com.mysql.jdbc.Util.handleNewInstance(Util.java:377)
com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:395)
com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:325)
java.sql/java.sql.DriverManager.getConnection(DriverManager.java:681)
java.sql/java.sql.DriverManager.getConnection(DriverManager.java:190)
org.apache.ibatis.datasource.unpooled.UnpooledDataSource.doGetConnection(UnpooledDataSource.java:224)
org.apache.ibatis.datasource.unpooled.UnpooledDataSource.doGetConnection(UnpooledDataSource.java:219)
org.apache.ibatis.datasource.unpooled.UnpooledDataSource.getConnection(UnpooledDataSource.java:95)
org.apache.ibatis.datasource.pooled.PooledDataSource.popConnection(PooledDataSource.java:432)
org.apache.ibatis.datasource.pooled.PooledDataSource.getConnection(PooledDataSource.java:89)
org.apache.ibatis.transaction.jdbc.JdbcTransaction.openConnection(JdbcTransaction.java:139)
org.apache.ibatis.transaction.jdbc.JdbcTransaction.getConnection(JdbcTransaction.java:61)
org.apache.ibatis.executor.BaseExecutor.getConnection(BaseExecutor.java:337)
org.apache.ibatis.executor.SimpleExecutor.prepareStatement(SimpleExecutor.java:86)
org.apache.ibatis.executor.SimpleExecutor.doQuery(SimpleExecutor.java:62)
org.apache.ibatis.executor.BaseExecutor.queryFromDatabase(BaseExecutor.java:325)
org.apache.ibatis.executor.BaseExecutor.query(BaseExecutor.java:156)
org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:109)
org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:89)
org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:147)
org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:140)
org.apache.ibatis.binding.MapperMethod.executeForMany(MapperMethod.java:147)
org.apache.ibatis.binding.MapperMethod.execute(MapperMethod.java:80)
org.apache.ibatis.binding.MapperProxy$PlainMethodInvoker.invoke(MapperProxy.java:152)
org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:85)
jdk.proxy4/jdk.proxy4.$Proxy30.selectAll(Unknown Source)
com.cxy.service.impl.BrandServiceImpl.selectAll(BrandServiceImpl.java:22)
com.cxy.web.servlet.SelectAllServlet.doGet(SelectAllServlet.java:21)
javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:51)
root cause

java.lang.NullPointerException: Cannot invoke "java.util.Map.get(Object)" because "this.serverVariables" is null
com.mysql.jdbc.ConnectionImpl.getServerCharset(ConnectionImpl.java:2983)
com.mysql.jdbc.MysqlIO.sendConnectionAttributes(MysqlIO.java:1873)
com.mysql.jdbc.MysqlIO.proceedHandshakeWithPluggableAuthentication(MysqlIO.java:1802)
com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1206)
com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2234)
com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2265)
com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2064)
com.mysql.jdbc.ConnectionImpl.(ConnectionImpl.java:790)
com.mysql.jdbc.JDBC4Connection.(JDBC4Connection.java:44)
java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:77)
java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:499)
java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:480)
com.mysql.jdbc.Util.handleNewInstance(Util.java:377)
com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:395)
com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:325)
java.sql/java.sql.DriverManager.getConnection(DriverManager.java:681)
java.sql/java.sql.DriverManager.getConnection(DriverManager.java:190)
org.apache.ibatis.datasource.unpooled.UnpooledDataSource.doGetConnection(UnpooledDataSource.java:224)
org.apache.ibatis.datasource.unpooled.UnpooledDataSource.doGetConnection(UnpooledDataSource.java:219)
org.apache.ibatis.datasource.unpooled.UnpooledDataSource.getConnection(UnpooledDataSource.java:95)
org.apache.ibatis.datasource.pooled.PooledDataSource.popConnection(PooledDataSource.java:432)
org.apache.ibatis.datasource.pooled.PooledDataSource.getConnection(PooledDataSource.java:89)
org.apache.ibatis.transaction.jdbc.JdbcTransaction.openConnection(JdbcTransaction.java:139)
org.apache.ibatis.transaction.jdbc.JdbcTransaction.getConnection(JdbcTransaction.java:61)
org.apache.ibatis.executor.BaseExecutor.getConnection(BaseExecutor.java:337)
org.apache.ibatis.executor.SimpleExecutor.prepareStatement(SimpleExecutor.java:86)
org.apache.ibatis.executor.SimpleExecutor.doQuery(SimpleExecutor.java:62)
org.apache.ibatis.executor.BaseExecutor.queryFromDatabase(BaseExecutor.java:325)
org.apache.ibatis.executor.BaseExecutor.query(BaseExecutor.java:156)
org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:109)
org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:89)
org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:147)
org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:140)
org.apache.ibatis.binding.MapperMethod.executeForMany(MapperMethod.java:147)
org.apache.ibatis.binding.MapperMethod.execute(MapperMethod.java:80)
org.apache.ibatis.binding.MapperProxy$PlainMethodInvoker.invoke(MapperProxy.java:152)
org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:85)
jdk.proxy4/jdk.proxy4.$Proxy30.selectAll(Unknown Source)
com.cxy.service.impl.BrandServiceImpl.selectAll(BrandServiceImpl.java:22)
com.cxy.web.servlet.SelectAllServlet.doGet(SelectAllServlet.java:21)
javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:51)
note The full stack trace of the root cause is available in the Apache Tomcat/7.0.47 logs.

  • 写回答

2条回答 默认 最新

  • 专家-赤兔[在线] 全栈领域优质创作者 2024-06-03 17:42
    关注

    引自免费微信小程序:皆我百晓生

    看起来你遇到了一个典型的Web应用错误,主要涉及到MyBatis数据访问框架、MySQL数据库连接以及Tomcat服务器。根据错误信息,问题似乎出在尝试从数据库获取数据时,导致了HTTP Status 500 - Internal Server Error

    以下是可能的解决步骤:

    1. 检查数据库连接配置: 确保你的数据库连接参数(如URL、用户名、密码)正确无误,并且数据库服务已经启动。这些参数通常在MyBatis的配置文件(例如:mybatis-config.xml)或者Spring Boot等框架的配置类中设置。

    2. 检查驱动程序版本: 确认使用的MySQL JDBC驱动程序与MySQL服务器版本兼容。有时,旧的驱动程序可能不支持新版本的MySQL,这会导致连接失败。可以尝试更新到最新版的MySQL Connector/J。

    3. 排查日志中的Null Pointer Exception: 堆栈跟踪显示了一个NullPointerException,这可能是由于在尝试获取未初始化的变量值。在com.mysql.jdbc.ConnectionImpl.getServerCharset()方法中,这可能是由于服务器变量没有被正确地初始化。这个异常通常意味着在调用此方法之前,应该先检查相关对象是否为null。

    4. 检查代码逻辑: 在BrandServiceImpl.java和SelectAllServlet.java文件中查找可能导致空指针异常的地方。确保所有依赖的对象在使用前都已正确初始化。

    5. 启用详细日志: 为了更好地定位问题,开启更详细的日志输出,包括MyBatis、数据库连接和应用程序级别的日志。这样可以帮助你看到更具体的错误信息,从而找到问题所在。

    6. 测试数据库连接: 通过编写简单的Java程序或者使用命令行工具(如MySQL Workbench或命令行客户端)直接测试数据库连接,确保能成功连接并执行查询。

    7. 清理项目并重新构建: 有时候,缓存的问题也可能导致此类错误。清理项目并重新构建可能会解决问题。

    8. 检查Tomcat配置: 确保Tomcat服务器的配置没有问题,比如端口冲突、内存溢出等。

    9. 更新依赖库: 确保所有的依赖库都是最新的,特别是MyBatis和MySQL JDBC驱动,以防止因库的bug导致的问题。

    10. 重启服务器: 在尝试过上述所有步骤后,如果问题依然存在,尝试重启服务器,有时候系统资源的释放或重置可以解决问题。

    如果你需要具体修改代码的部分,提供相关代码后我可以给出更精确的建议。同时,如果你有配置文件或其他相关信息,那将有助于更准确地诊断问题。

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  • 创建了问题 6月3日

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