jsp代码:
<jsp:useBean id="db" class="data.data" scope="page" />
<%
String id=(String)session.getAttribute("id");
ResultSet rs=db.executeQuery(id);
rs.next();
double moy=rs.getDouble(4);
if(moy<30){
out.print("<script language='javaScript'> alert('余额不足,请及时充值');</script>");
response.setHeader("refresh", "0;url=xiamu.jsp");
}
else{
out.print(moy); //测试能否读出数据
moy=moy-30;
db.execQuery(id);!!!!就这行错误
session.setAttribute("moy",moy);
out.print(moy);
}
%>
从其他页面读取id,先通过id获取表中数据(这里能读出来),关键是下面,将读取的moy值修改后,通过另一个方法写入数据库报错
java数据库代码:(连接什么的省略)
public void execQuery(String id){
ResultSet rs = null;//订票功能,修改moy值
try {
rs = stmt.executeQuery("SELECT * FROM user where id='"+id+"'");
rs.next();
double moy=rs.getDouble(4);
moy=moy-30;
stmt.executeUpdate("UPDATE user SET moy ='"+moy+"' WHERE id ='"+id+"'");
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
顺便贴上没有错误的查询代码:
public ResultSet executeQuery(String id) { //登录判断,查询
ResultSet rs = null;
try {
rs = stmt.executeQuery("SELECT * FROM user where id='"+id+"'");
} catch (Exception ex) {
}
return rs;
}
最后是报错信息:
三月 20, 2019 12:09:33 下午 org.apache.catalina.core.StandardWrapperValve invoke
严重: Servlet.service() for servlet [jsp] in context with path [/yangyangCinema] threw exception [An exception occurred processing JSP page /login3.jsp at line 4138: out.print(moy); //鍓嶅??
39: out.print(id);
40: moy=moy-30;
41: db.execQuery(id);
42: session.setAttribute("moy",moy);
43: out.print(moy);
44: }
Stacktrace:] with root cause
java.lang.NoSuchMethodError: data.data.execQuery(Ljava/lang/String;)V
at org.apache.jsp.login3_jsp._jspService(login3_jsp.java:165)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:443)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:385)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:329)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:230)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165)
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:474)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:624)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:349)
at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:783)
at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)
at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:789)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1437)
at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:745)
》》》》》》求大佬啊!!!!!
<jsp:useBean id="db" class="data.data" scope="page" />
<%
String id=(String)session.getAttribute("id");
ResultSet rs=db.executeQuery(id);
rs.next();
double moy=rs.getDouble(4);
if(moy<30){
out.print("<script language='javaScript'> alert('余额不足,请及时充值');</script>");
response.setHeader("refresh", "0;url=xiamu.jsp");
}
else{
out.print(moy); //测试能否读出数据
moy=moy-30;
db.execQuery(id);!!!!就这行错误
session.setAttribute("moy",moy);
out.print(moy);
}
%>
从其他页面读取id,先通过id获取表中数据(这里能读出来),关键是下面,将读取的moy值修改后,通过另一个方法写入数据库报错
java数据库代码:(连接什么的省略)
public void execQuery(String id){
ResultSet rs = null;//订票功能,修改moy值
try {
rs = stmt.executeQuery("SELECT * FROM user where id='"+id+"'");
rs.next();
double moy=rs.getDouble(4);
moy=moy-30;
stmt.executeUpdate("UPDATE user SET moy ='"+moy+"' WHERE id ='"+id+"'");
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
顺便贴上没有错误的查询代码:
public ResultSet executeQuery(String id) { //登录判断,查询
ResultSet rs = null;
try {
rs = stmt.executeQuery("SELECT * FROM user where id='"+id+"'");
} catch (Exception ex) {
}
return rs;
}
最后是报错信息:
三月 20, 2019 12:09:33 下午 org.apache.catalina.core.StandardWrapperValve invoke
严重: Servlet.service() for servlet [jsp] in context with path [/yangyangCinema] threw exception [An exception occurred processing JSP page /login3.jsp at line 4138: out.print(moy); //鍓嶅??
39: out.print(id);
40: moy=moy-30;
41: db.execQuery(id);
42: session.setAttribute("moy",moy);
43: out.print(moy);
44: }
Stacktrace:] with root cause
java.lang.NoSuchMethodError: data.data.execQuery(Ljava/lang/String;)V
at org.apache.jsp.login3_jsp._jspService(login3_jsp.java:165)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:443)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:385)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:329)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:230)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165)
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:474)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:624)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:349)
at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:783)
at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)
at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:789)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1437)
at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:745)
》》》》》》求大佬啊!!!!!
换一种运行方式试试看,stmt.execute(sql)