HTTP Status 500 – Internal Server Error

Type Exception Report

Message com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Data source rejected establishment of connection, message from server: "Too many connections"

Description The server encountered an unexpected condition that prevented it from fulfilling the request.

Exception

java.lang.RuntimeException: com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Data source rejected establishment of connection,  message from server: "Too many connections"
	com.yuyouword.dao.BaseDAO.getConnection(BaseDAO.java:36)
	com.yuyouword.dao.WebDAO.findWorkCountByCondition(WebDAO.java:565)
	com.yuyouword.service.WebService.findWorkCountByCondition(WebService.java:51)
	com.yuyouword.servlet.GetWorksPaginationServlet.doGet(GetWorksPaginationServlet.java:65)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:634)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:741)
	org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)

Root Cause

com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Data source rejected establishment of connection,  message from server: "Too many connections"
	sun.reflect.GeneratedConstructorAccessor63.newInstance(Unknown Source)
	sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
	java.lang.reflect.Constructor.newInstance(Unknown Source)
	com.mysql.jdbc.Util.handleNewInstance(Util.java:389)
	com.mysql.jdbc.Util.getInstance(Util.java:372)
	com.mysql.jdbc.SQLError.createSQLException(SQLError.java:958)
	com.mysql.jdbc.SQLError.createSQLException(SQLError.java:937)
	com.mysql.jdbc.SQLError.createSQLException(SQLError.java:926)
	com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1037)
	com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2239)
	com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2270)
	com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2069)
	com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:794)
	com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:44)
	sun.reflect.GeneratedConstructorAccessor10.newInstance(Unknown Source)
	sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
	java.lang.reflect.Constructor.newInstance(Unknown Source)
	com.mysql.jdbc.Util.handleNewInstance(Util.java:389)
	com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:399)
	com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:325)
	java.sql.DriverManager.getConnection(Unknown Source)
	java.sql.DriverManager.getConnection(Unknown Source)
	com.yuyouword.dao.BaseDAO.getConnection(BaseDAO.java:34)
	com.yuyouword.dao.WebDAO.findWorkCountByCondition(WebDAO.java:565)
	com.yuyouword.service.WebService.findWorkCountByCondition(WebService.java:51)
	com.yuyouword.servlet.GetWorksPaginationServlet.doGet(GetWorksPaginationServlet.java:65)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:634)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:741)
	org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)

Note The full stack trace of the root cause is available in the server logs.

HTTP Status 500 – Internal Server Error

Apache Tomcat/9.0.11