JSP + MySQL
Привет всем!
У меня есть JSP код, он не работает....
db.dbmanage.java:
/*
* To change this template, choose Tools | Templates
* and open the template in the editor.
*/
package db;
import java.sql.Connection;
import java.sql.Statement;
import java.sql.ResultSet;
import java.sql.DriverManager;
/**
*
* @author 1
*/
public class dbmanage {
Connection con;
Statement st;
ResultSet rs;
String constr = "jdbc:mysql://localhost:3306/mysql";
public dbmanage()
{
}
public String readdb()
{
try {
con = DriverManager.getConnection(constr, "root", "");
} catch (Exception e) {
e.printStackTrace();
}
return con.toString();
}
}
index.jsp:
<%--
Document : index
Created on : 05.11.2011, 22:03:15
Author : 1
--%>
<%@page contentType="text/html" pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>JSP Page</title>
</head>
<body>
<h1>Hello World!</h1>
<%=new db.dbmanage().readdb() %>
</body>
</html>
выдаёт ошибку:
HTTP Status 500 -
type Exception report
message
descriptionThe server encountered an internal error () that prevented it from fulfilling this request.
exception
org.apache.jasper.JasperException: java.lang.NullPointerException
root cause
java.lang.NullPointerException
note The full stack traces of the exception and its root causes are available in the GlassFish Server Open Source Edition 3.1.1 logs.
GlassFish Server Open Source Edition 3.1.1
stack trace:
java.lang.NullPointerException
at db.dbmanage.readdb(dbmanage.java:33)
at org.apache.jsp.index_jsp._jspService(index_jsp.java:57)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:111)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:847)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:403)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:492)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:378)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:847)
at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1539)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:281)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:655)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:595)
at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:98)
at com.sun.enterprise.web.PESessionLockingStandardPipeline.invoke(PESessionLockingStandardPipeline.java:91)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:162)
at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:330)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:231)
at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:174)
at com.sun.grizzly.http.ProcessorTask.invokeAdapter(ProcessorTask.java:828)
at com.sun.grizzly.http.ProcessorTask.doProcess(ProcessorTask.java:725)
at com.sun.grizzly.http.ProcessorTask.process(ProcessorTask.java:1019)
at com.sun.grizzly.http.DefaultProtocolFilter.execute(DefaultProtocolFilter.java:225)
at com.sun.grizzly.DefaultProtocolChain.executeProtocolFilter(DefaultProtocolChain.java:137)
at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:104)
at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:90)
at com.sun.grizzly.http.HttpProtocolChain.execute(HttpProtocolChain.java:79)
at com.sun.grizzly.ProtocolChainContextTask.doCall(ProtocolChainContextTask.java:54)
at com.sun.grizzly.SelectionKeyContextTask.call(SelectionKeyContextTask.java:59)
at com.sun.grizzly.ContextTask.run(ContextTask.java:71)
at com.sun.grizzly.util.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:532)
at com.sun.grizzly.util.AbstractThreadPool$Worker.run(AbstractThreadPool.java:513)
at java.lang.Thread.run(Thread.java:729)
С базой все норм, пару раз проверил. Программа только проверяет соединение с базой и выводит класс в виде текста. Почему-то con остается нулем....
В чем проблема???
Сделал дебаг:
java.sql.SQLException: No suitable driver found for jdbc:mysql://localhost:3306/mysql
У меня есть JSP код, он не работает....
db.dbmanage.java:
/*
* To change this template, choose Tools | Templates
* and open the template in the editor.
*/
package db;
import java.sql.Connection;
import java.sql.Statement;
import java.sql.ResultSet;
import java.sql.DriverManager;
/**
*
* @author 1
*/
public class dbmanage {
Connection con;
Statement st;
ResultSet rs;
String constr = "jdbc:mysql://localhost:3306/mysql";
public dbmanage()
{
}
public String readdb()
{
try {
con = DriverManager.getConnection(constr, "root", "");
} catch (Exception e) {
e.printStackTrace();
}
return con.toString();
}
}
index.jsp:
<%--
Document : index
Created on : 05.11.2011, 22:03:15
Author : 1
--%>
<%@page contentType="text/html" pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>JSP Page</title>
</head>
<body>
<h1>Hello World!</h1>
<%=new db.dbmanage().readdb() %>
</body>
</html>
выдаёт ошибку:
HTTP Status 500 -
type Exception report
message
descriptionThe server encountered an internal error () that prevented it from fulfilling this request.
exception
org.apache.jasper.JasperException: java.lang.NullPointerException
root cause
java.lang.NullPointerException
note The full stack traces of the exception and its root causes are available in the GlassFish Server Open Source Edition 3.1.1 logs.
GlassFish Server Open Source Edition 3.1.1
stack trace:
java.lang.NullPointerException
at db.dbmanage.readdb(dbmanage.java:33)
at org.apache.jsp.index_jsp._jspService(index_jsp.java:57)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:111)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:847)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:403)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:492)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:378)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:847)
at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1539)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:281)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:655)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:595)
at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:98)
at com.sun.enterprise.web.PESessionLockingStandardPipeline.invoke(PESessionLockingStandardPipeline.java:91)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:162)
at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:330)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:231)
at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:174)
at com.sun.grizzly.http.ProcessorTask.invokeAdapter(ProcessorTask.java:828)
at com.sun.grizzly.http.ProcessorTask.doProcess(ProcessorTask.java:725)
at com.sun.grizzly.http.ProcessorTask.process(ProcessorTask.java:1019)
at com.sun.grizzly.http.DefaultProtocolFilter.execute(DefaultProtocolFilter.java:225)
at com.sun.grizzly.DefaultProtocolChain.executeProtocolFilter(DefaultProtocolChain.java:137)
at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:104)
at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:90)
at com.sun.grizzly.http.HttpProtocolChain.execute(HttpProtocolChain.java:79)
at com.sun.grizzly.ProtocolChainContextTask.doCall(ProtocolChainContextTask.java:54)
at com.sun.grizzly.SelectionKeyContextTask.call(SelectionKeyContextTask.java:59)
at com.sun.grizzly.ContextTask.run(ContextTask.java:71)
at com.sun.grizzly.util.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:532)
at com.sun.grizzly.util.AbstractThreadPool$Worker.run(AbstractThreadPool.java:513)
at java.lang.Thread.run(Thread.java:729)
С базой все норм, пару раз проверил. Программа только проверяет соединение с базой и выводит класс в виде текста. Почему-то con остается нулем....
В чем проблема???
Сделал дебаг:
java.sql.SQLException: No suitable driver found for jdbc:mysql://localhost:3306/mysql
Ну. Так в дебаге же написано. Ищите в сети "Connect to MySQL with JDBC driver"
JDBC драйвер то доступен томкату?