使用dao程模仿老師那個分頁功能,為啥網頁顯示500,后臺報錯,怎么解決?
?Servlet.service() for servlet [JdbcSqlServlet] in context with path [/pager] threw exception
java.lang.RuntimeException: 查詢所有數據異常
at com.cxl.page.service.impl.JdbcSqLStudentImpl.findStudent(JdbcSqLStudentImpl.java:77)
at com.cxl.page.service.impl.JdbcSqlStudentServiceImpl.findStudent(JdbcSqlStudentServiceImpl.java:20)
at com.cxl.page.servlet.JdbcSqlServlet.doPost(JdbcSqlServlet.java:66)
at com.cxl.page.servlet.JdbcSqlServlet.doGet(JdbcSqlServlet.java:26)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:635)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:742)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:198)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:478)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:80)
at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:650)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342)
at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:799)
at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)
at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:868)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1457)
at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
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)
Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '5' at line 1
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
at com.mysql.jdbc.Util.getInstance(Util.java:386)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1053)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4120)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4052)
at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2503)
at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2664)
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2794)
at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:2155)
at com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:2322)
at com.cxl.page.util.JdbcUtil.findResult(JdbcUtil.java:128)
at com.cxl.page.service.impl.JdbcSqLStudentImpl.findStudent(JdbcSqLStudentImpl.java:61)
... 27 more
拋出這些異常,該怎么解決,有知道的幫助解決下,老師的原代碼有地方下載么,照著對了好幾遍沒找到錯誤點。
2017-12-10
數據庫有打開嗎
2017-10-14
at com.cxl.page.service.impl.JdbcSqLStudentImpl.findStudent(JdbcSqLStudentImpl.java:77)
at com.cxl.page.service.impl.JdbcSqlStudentServiceImpl.findStudent(JdbcSqlStudentServiceImpl.java:20)
at com.cxl.page.servlet.JdbcSqlServlet.doPost(JdbcSqlServlet.java:66)
at com.cxl.page.servlet.JdbcSqlServlet.doGet(JdbcSqlServlet.java:26)
看你這些類中是否有轉化不對的地方.