我正在尝试在java中的MySQL数据库usign jdbc中添加一些记录。该程序对100条记录绝对有效。但是在100条记录之后，我得到以下错误。
Exception occured while obtaining
connectionjava.sql.SQLNonTransientConnectionException: Could not create connection to database server.
java.lang.NullPointerException
at com.rest.EmployeeRest.insertDesigMySQLData(EmployeeRest.java:446)
at com.rest.EmployeeRest.syncDesignation(EmployeeRest.java:188)
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 com.sun.jersey.spi.container.JavaMethodInvokerFactory$1.invoke(JavaMethodInvokerFactory.java:60)
at com.sun.jersey.server.impl.model.method.dispatch.AbstractResourceMethodDispatchProvider$ResponseOutInvoker._dispatch(AbstractResourceMethodDispatchProvider.java:205)
at com.sun.jersey.server.impl.model.method.dispatch.ResourceJavaMethodDispatcher.dispatch(ResourceJavaMethodDispatcher.java:75)
at com.sun.jersey.server.impl.uri.rules.HttpMethodRule.accept(HttpMethodRule.java:302)
at com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.java:147)
at com.sun.jersey.server.impl.uri.rules.ResourceClassRule.accept(ResourceClassRule.java:108)
at com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.java:147)
at com.sun.jersey.server.impl.uri.rules.RootResourceClassesRule.accept(RootResourceClassesRule.java:84)
at com.sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.java:1542)
at com.sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.java:1473)
at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:1419)
at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:1409)
at com.sun.jersey.spi.container.servlet.WebComponent.service(WebComponent.java:409)
at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:558)
at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:733)
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 org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:218)
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:442)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1082)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:623)
at org.apache.tomcat.util.net.JIoEndpoint$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)
在google上出现此错误后，有人告诉要在localhost 3306（MySQL端口）上使用telnet命令。并显示“连接过多”错误。 谁能帮我解决这个问题。
获取数据并添加到MySQL的API代码：
ArrayList<Employee> arrDesig = getAllDesig();
setTotRecords(arrDesig.size());
System.out.println("Oracle TotRecords = "+getTotRecords());
if(arrDesig.size() > 0){
for(int iCnt=0; iCnt<arrDesig.size(); iCnt++){
if(insertDesigMySQLData(arrDesig.get(iCnt)) == 1){
mysqlDat++;
}
System.out.println("MySQL inserted data = "+mysqlDat);
}
if(getTotRecords() == mysqlDat){
retval = 1;
}else{
retval = 0;
}
}else{
retval = 0;
}
要添加的MySQL代码：
int retval = 0;
OracleDataSource objMySQLDataSource = new OracleDataSource("mysql");
try{
Connection connection = objMySQLDataSource.getDbConnection();
CallableStatement pstmt=connection.prepareCall("{call addDesig(?,?,?)}");
pstmt.setString(1,objEmployee.getDesig_id());
System.out.println("getDesig_id() = "+objEmployee.getDesig_id());
pstmt.setString(2,objEmployee.getDesig_nm());
System.out.println("getDesig_nm() = "+objEmployee.getDesig_nm());
pstmt.registerOutParameter(3, Types.NUMERIC);
pstmt.executeUpdate();
retval = pstmt.getInt(3);
pstmt.close();
}catch (Exception e) {
retval = 0;
e.printStackTrace();
}finally{
objMySQLDataSource.connectionClose();
}
return retval;
Oracle连接
OracleDataSource(){
setUrl("jdbc:oracle:thin:@dburl");
setDriver("oracle.jdbc.OracleDriver");
setUserName("admin");
setPassword("**********");
}
MySQL连接
OracleDataSource(String mysql){
setUrl("jdbc:mysql://localhost:3306/academicdb?verifyServerCertificate=false&useSSL=true&useUnicode=true&useJDBCCompliantTimezoneShift=true&useLegacyDatetimeCode=false&serverTimezone=UTC");
setDriver("com.mysql.cj.jdbc.Driver");//com.mysql.jdbc.Driver
setUserName("root");
setPassword("");
}
public Connection getDbConnection() {
Connection con = null;
try{
Class.forName(getDriver());
con = DriverManager.getConnection(getUrl(), getUserName(), getPassword());
} catch (Exception se) {
System.out.println("Exception occured while obtaining connection" + se.toString());
}
return con;
}