【发布时间】：2016-05-12 08:47:43
【问题描述】：
我们有一个使用 servlet、jsps 和 Threads 的 Web 应用程序，这是一个多线程应用程序。我们使用JDK1.8，Wildfly server 8.2。我创建了一个如下所示的ContextListener来使用JNDI数据源获取连接对象。这是使用连接池获取连接的正确方法吗？
AppContextListener.java
public class AppContextListener implements ServletContextListener
{
/* (non-Javadoc)
* @see javax.servlet.ServletContextListener#contextDestroyed(javax.servlet.ServletContextEvent)
*/
@Override
public void contextDestroyed(ServletContextEvent servletContextEvent)
{
ServletContext ctx = servletContextEvent.getServletContext();
DBConnectionManager dbManager = (DBConnectionManager)ctx.getAttribute("DBManager");
dbManager.closeConnection();
}
/* (non-Javadoc)
* @see javax.servlet.ServletContextListener#contextInitialized(javax.servlet.ServletContextEvent)
*/
@Override
public void contextInitialized(ServletContextEvent servletContextEvent)
{
ServletContext ctx = servletContextEvent.getServletContext();
String jndiName = ctx.getInitParameter("JNDI");
//create database connection from context parameters and set it to context
DBConnectionManager dbManager = new DBConnectionManager(jndiName);
ctx.setAttribute("DBManager", dbManager);
}
}
DBConnectionManager.java
public class DBConnectionManager
{
private static Logger logger=Logger.getLogger(DBConnectionManager.class);
private static Connection conn;
private String jndiName;
public DBConnectionManager(String jndiName) {
this.jndiName = jndiName;
try {
Context ctx = new InitialContext();
DataSource ds = (DataSource) ctx.lookup(this.jndiName);
conn = ds.getConnection();
conn.setAutoCommit(false);
} catch (NamingException | SQLException e) {
logger.error("[DBConnectionManager.DBConnectionManager]Exception: "+e.getMessage());
}
}
public static Connection getConnection(){
return conn;
}
public void closeConnection(){
if(conn != null){
try {
conn.close();
} catch (SQLException e) {
logger.error("[DBConnectionManager.closeConnection]Exception: "+e.getMessage());
}
}
}
}
每当我需要一个连接对象时，我都会调用静态方法 getConnection()。似乎我没有使用这种方式实现连接池。我应该如何获得连接以实现连接池？
我的服务器将运行超过 12 小时，当我尝试重新加载发送的消息时，表系统将抛出以下由线程引起的异常。我该如何解决这个问题？
TxConnectionListener:380 - IJ000305: Connection error occured: org.jboss.jca.core.connectionmanager.listener.TxConnectionListener@bed9492[state=NORMAL managed connection=org.jboss.jca.adapters.jdbc.local.LocalManagedConnection@5df6b58b connection handles=1 lastUse=1462985106208 trackByTx=false pool=org.jboss.jca.core.connectionmanager.pool.strategy.OnePool@1299562a mcp=SemaphoreArrayListManagedConnectionPool@3a1d6b71[pool=RDTSDS] xaResource=LocalXAResourceImpl@4b534943[connectionListener=bed9492 connectionManager=f7fbabb warned=false currentXid=null productName=Oracle productVersion=Oracle Database 12c Enterprise Edition Release 12.1.0.2.0 - 64bit Production
With the Partitioning, OLAP, Advanced Analytics and Real Application Testing options jndiName=java:jboss/RDTSDS] txSync=null]
javax.resource.spi.ResourceAdapterInternalException: Unexpected error
at org.jboss.jca.adapters.jdbc.BaseWrapperManagedConnection.broadcastConnectionError(BaseWrapperManagedConnection.java:644)
at org.jboss.jca.adapters.jdbc.BaseWrapperManagedConnection.connectionError(BaseWrapperManagedConnection.java:610)
at org.jboss.jca.adapters.jdbc.WrappedConnection.checkException(WrappedConnection.java:1640)
at org.jboss.jca.adapters.jdbc.WrappedStatement.checkException(WrappedStatement.java:1267)
at org.jboss.jca.adapters.jdbc.WrappedPreparedStatement.executeQuery(WrappedPreparedStatement.java:467)
at com.ctsu.rdts.beans.ReconcileInfo.getNextMessage(ReconcileInfo.java:493)
at com.ctsu.rdts.beans.GroupInfo.sendMessage(GroupInfo.java:818)
at com.ctsu.rdts.app.GroupSendThread.send(GroupSendThread.java:114)
at com.ctsu.rdts.app.GroupSendThread.run(GroupSendThread.java:68)
Caused by: java.lang.ThreadDeath
at java.lang.Thread.stop(Thread.java:850)
at com.ctsu.rdts.app.HttpDequeue.stopThread(HttpDequeue.java:944)
at com.ctsu.rdts.app.HttpDequeue.clearLocks(HttpDequeue.java:418)
at com.ctsu.rdts.app.HttpDequeue.run(HttpDequeue.java:404)
服务器日志中的异常：
WARN [org.jboss.as.connector.subsystems.datasources.AbstractDataSourceService$WildFlyLocalMCF] (NRG) Queued thread: ECOG-ACRIN: java.lang.Throwable: Queued thread: ECOG-ACRIN
at sun.misc.Unsafe.park(Native Method) [rt.jar:1.8.0_66]
at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175) [rt.jar:1.8.0_66]
at java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInterrupt(AbstractQueuedSynchronizer.java:836) [rt.jar:1.8.0_66]
at java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireQueued(AbstractQueuedSynchronizer.java:870) [rt.jar:1.8.0_66]
at java.util.concurrent.locks.AbstractQueuedSynchronizer.acquire(AbstractQueuedSynchronizer.java:1199) [rt.jar:1.8.0_66]
at java.util.concurrent.locks.ReentrantLock$FairSync.lock(ReentrantLock.java:224) [rt.jar:1.8.0_66]
at java.util.concurrent.locks.ReentrantLock.lock(ReentrantLock.java:285) [rt.jar:1.8.0_66]
at org.jboss.jca.adapters.jdbc.BaseWrapperManagedConnection.lock(BaseWrapperManagedConnection.java:373)
at org.jboss.jca.adapters.jdbc.BaseWrapperManagedConnection.tryLock(BaseWrapperManagedConnection.java:388)
at org.jboss.jca.adapters.jdbc.WrappedConnection.lock(WrappedConnection.java:147)
at org.jboss.jca.adapters.jdbc.WrappedConnection.prepareCall(WrappedConnection.java:589)
自 15 天以来，我一直陷入这个问题。有人可以帮我解决这个问题吗？
【问题讨论】：
标签： java multithreading servlets threadpool connection-pooling