实际上我在使用MySQL数据库时遇到了麻烦，我正在下面提到的工作环境中工作。
我的eclipse数据库连接中的带有MySQL DB的Java spring应用程序成功建立并且运行良好。
但是，在将其制成war文件之后，我将其部署在同一台PC上运行的Tomcat服务器上。
在这种情况下，数据库未连接，并且出现以下异常。
请建议我解决此问题
1.0-20160813-CMS:08-Jan-2019 11:33:03 PM : com.mysql.jdbc.CommunicationsException -->
DbUtil : getConnection com.mysql.jdbc.Connection.createNewIO(Connection.java:2820)
com.mysql.jdbc.Connection.<init>(Connection.java:1553)
com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:285)
java.sql.DriverManager.getConnection(DriverManager.java:664)
java.sql.DriverManager.getConnection(DriverManager.java:247)
com.sardonyx.dbaccess.DbUtil.getConnection(DbUtil.java:19)
com.sardonyx.dbaccess.DataAccess.callquery(DataAccess.java:5651)
com.sardonyx.dbaccess.DataAccess.querytoInt(DataAccess.java:1385)
com.sardonyx.dbaccess.DataAccess.getStringResourceModule(DataAccess.java:1365)
com.sardonyx.server.CommonServlet.doPost(CommonServlet.java:197)
javax.servlet.http.HttpServlet.service(HttpServlet.java:650)
javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:218)org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:110)org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:506)org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:169)org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:962)org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:445)org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1087)org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:637)org.apache.tomcat.ut!
il.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:318)java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)java.lang.Thread.run(Thread.java:748)