我正在使用spring 2.5 SimpleJdbcTemplate来访问MySQL数据库。当我试图经常访问数据库时（使用Quartz每分钟访问它）我得到这个堆栈跟踪：
org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is org.apache.commons.dbcp.SQLNestedException: Cannot create PoolableConnectionFactory (Communications link failure
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.)
at org.springframework.jdbc.datasource.DataSourceUtils.getConnection(DataSourceUtils.java:82)
at org.springframework.jdbc.core.JdbcTemplate.execute(JdbcTemplate.java:382)
at org.springframework.jdbc.core.JdbcTemplate.query(JdbcTemplate.java:458)
at org.springframework.jdbc.core.JdbcTemplate.query(JdbcTemplate.java:466)
at org.springframework.jdbc.core.JdbcTemplate.queryForList(JdbcTemplate.java:497)
at org.springframework.jdbc.core.simple.SimpleJdbcTemplate.queryForList(SimpleJdbcTemplate.java:223)
at com.db.timexis.dao.UserDaoJdbc.getListOfAllUsers(UserDaoJdbc.java:137)
at com.db.timexis.service.AuthServiceImpl.getListOfAllUsers(AuthServiceImpl.java:77)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:307)
at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:182)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:149)
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:106)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:171)
at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:89)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:171)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:204)
at $Proxy0.getListOfAllUsers(Unknown Source)
at com.mail.timexis.ReminderBean.execute(ReminderBean.java:25)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.springframework.util.MethodInvoker.invoke(MethodInvoker.java:276)
at org.springframework.scheduling.quartz.MethodInvokingJobDetailFactoryBean$MethodInvokingJob.executeInternal(MethodInvokingJobDetailFactoryBean.java:260)
at org.springframework.scheduling.quartz.QuartzJobBean.execute(QuartzJobBean.java:86)
at org.quartz.core.JobRunShell.run(JobRunShell.java:216)
at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:549)
Caused by: org.apache.commons.dbcp.SQLNestedException: Cannot create PoolableConnectionFactory (Communications link failure
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.)
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:113)
at org.springframework.jdbc.datasource.DataSourceUtils.getConnection(DataSourceUtils.java:79)
... 30 more
Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:409)
at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1122)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2260)
at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:787)
at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:49)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:409)
at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:357)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:285)
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)
... 33 more
Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: The driver was unable to create a connection due to an inability to establish the client portion of a socket.
This is usually caused by a limit on the number of sockets imposed by the operating system. This limit is usually configurable.
For Unix-based platforms, see the manual page for the 'ulimit' command. Kernel or system reconfiguration may also be required.
For Windows-based platforms, see Microsoft Knowledge Base Article 196271 (Q196271).
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:409)
at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1122)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:344)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2181)
... 46 more
Caused by: java.net.BindException: Address already in use: connect
at java.net.PlainSocketImpl.socketConnect(Native Method)
at java.net.PlainSocketImpl.doConnect(PlainSocketImpl.java:333)
at java.net.PlainSocketImpl.connectToAddress(PlainSocketImpl.java:195)
at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:182)
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:366)
at java.net.Socket.connect(Socket.java:519)
at java.net.Socket.connect(Socket.java:469)
at java.net.Socket.<init>(Socket.java:366)
at java.net.Socket.<init>(Socket.java:209)
at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:256)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:293)
... 47 more
每分钟执行的代码：
public void execute() {
List<User> regularUsers = null;
try {
// get all regular users
ApplicationContext ctx = new ClassPathXmlApplicationContext(
"applicationContext.xml");
AuthService authService = (AuthService) ctx.getBean("authService");
regularUsers = authService.getListOfAllUsers();
} catch (Exception e) {
e.printStackTrace();
}
try {
if (regularUsers != null) {
for (User u : regularUsers) {
if (u.getEmail().matches("^[_A-Za-z0-9-]+(\\.[_A-Za-z0-9-]+)*@[A-Za-z0-9-]+(\\.[A-Za-z0-9-]+)*(\\.[_A-Za-z0-9-]+)")) {
mailSender.sendMailReminder(u.getEmail(),
u.getFirstName());
// log mail sending
Date date = Calendar.getInstance().getTime();
SimpleDateFormat sdf = new SimpleDateFormat(
"yyyy/MM/dd HH:mm:ss");
String strDate = sdf.format(date);
System.out.println(strDate + "Reminder mail send...");
// log mail sending
}else{
System.out.println("invalid mail address");
}
}
}
} catch (Exception e) {
e.printStackTrace();
}
}
为了测试目的，它每分钟执行一次。它将在未来每周执行一次。
我的DBCP资产：
jdbc.maxActive=15
jdbc.maxIdle=10
jdbc.minIdle=5
jdbc.maxWait=5000
jdbc.validationQuery=select 1
jdbc.timeBetweenEvictionRunsMillis=1000
jdbc.numTestsPerEvictionRun=10
jdbc.minEvictableIdleTimeMillis=1200000
可以通过命令行访问数据库。
答案 0 :(得分：6)
请注意，每次调用方法时都会创建一个新的应用程序上下文实例，并且不要关闭它。这意味着在此上下文中由bean分配的资源（例如，由连接池创建的连接）不会被释放。
通常，您需要在应用程序启动期间仅创建一次应用程序上下文，并在关闭时关闭它，因此我建议您以这种方式实现它。
如果你需要在每次调用该方法时创建一个新的应用程序上下文，请不要忘记在方法结束时close()（在finally块中为了可靠性）。< / p>
另请注意，您应为连接池bean声明适当的destroy-method，以便在关闭上下文时释放资源。
答案 1 :(得分：1)
主要的例外是“java.net.BindException：Address in in use：connect”。看来你有连接池泄漏。您确定每个连接在使用后都已关闭吗？请检查一下。