代码如下
mysql.jsp<%@ page contentType="text/html; charset=gb2312" %>;
<html>;
<head>;
<title>;JSP连接MySQL!</title>;
</head>;
<body>;
<%@ page language="java" import="java.sql.*" %>;
<jsp:useBean id="DBconn1" scope="page" class="Mysqltest.DBconn" />;
<%
ResultSet RS = DBconn1.executeQuery("SELECT * FROM userinfo");
//userinfo为你的数据库表名
while (RS.next()) {
out.print("<h1>;" + RS.getString("username")+"+"+RS.getString("sex")+"+"+RS.getString("email")+"</h1>;");
//username、sex、email为字段名
}
RS.close();
%>;
</body >;
</html >;
bean文件
DBcoon.javapackage Mysqltest; import java.sql.*; public class DBconn {
String DBDriver = "org.gjt.mm.mysql.Driver";
String ConnStr = "jdbc:mysql://localhost/web"; //web为你的数据库名
String MyUser = ""; //用户名
String MyPassword = "";//密码 没有则为空。
Connection conn = null;
ResultSet rs = null;
public DBconn() {
try {
Class.forName(DBDriver);
}
catch (java.lang.ClassNotFoundException e) {
System.err.println("DBconn (): " + e.getMessage());
}
} public ResultSet executeQuery(String sql) {
rs = null;
try {
conn = DriverManager.getConnection(ConnStr, MyUser, MyPassword);
Statement stmt = conn.createStatement();
rs = stmt.executeQuery(sql);
}
catch (SQLException ex) {
System.err.println("aq.executeQuery:" + ex.getMessage());
}
return rs;
}
}
DBcoon.java编译通过
环境变量,驱动等都已经装好,表也建好了
出现的问题如下:
请各位大虾指点HTTP Status 500 - --------------------------------------------------------------------------------type Exception reportmessage description The server encountered an internal error () that prevented it from fulfilling this request.exception org.apache.jasper.JasperException: Exception in JSP: /mysql.jsp:129: <%
10: ResultSet RS = DBconn1.executeQuery("SELECT * FROM userinfo");
11: //userinfo为你的数据库表名
12: while (RS.next()) {
13: out.print("<h1>;" + RS.getString("username")+"+"+RS.getString("sex")+"+"+RS.getString("email")+"</h1>;");
14: //username、sex、email为字段名
15: }
Stacktrace:
org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:504)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:393)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:314)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:264)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
root cause java.lang.NullPointerException
org.apache.jsp.mysql_jsp._jspService(mysql_jsp.java:63)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:97)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:332)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:314)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:264)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
note The full stack trace of the root cause is available in the Apache Tomcat/5.5.17 logs.
--------------------------------------------------------------------------------Apache Tomcat/5.5.17
mysql.jsp<%@ page contentType="text/html; charset=gb2312" %>;
<html>;
<head>;
<title>;JSP连接MySQL!</title>;
</head>;
<body>;
<%@ page language="java" import="java.sql.*" %>;
<jsp:useBean id="DBconn1" scope="page" class="Mysqltest.DBconn" />;
<%
ResultSet RS = DBconn1.executeQuery("SELECT * FROM userinfo");
//userinfo为你的数据库表名
while (RS.next()) {
out.print("<h1>;" + RS.getString("username")+"+"+RS.getString("sex")+"+"+RS.getString("email")+"</h1>;");
//username、sex、email为字段名
}
RS.close();
%>;
</body >;
</html >;
bean文件
DBcoon.javapackage Mysqltest; import java.sql.*; public class DBconn {
String DBDriver = "org.gjt.mm.mysql.Driver";
String ConnStr = "jdbc:mysql://localhost/web"; //web为你的数据库名
String MyUser = ""; //用户名
String MyPassword = "";//密码 没有则为空。
Connection conn = null;
ResultSet rs = null;
public DBconn() {
try {
Class.forName(DBDriver);
}
catch (java.lang.ClassNotFoundException e) {
System.err.println("DBconn (): " + e.getMessage());
}
} public ResultSet executeQuery(String sql) {
rs = null;
try {
conn = DriverManager.getConnection(ConnStr, MyUser, MyPassword);
Statement stmt = conn.createStatement();
rs = stmt.executeQuery(sql);
}
catch (SQLException ex) {
System.err.println("aq.executeQuery:" + ex.getMessage());
}
return rs;
}
}
DBcoon.java编译通过
环境变量,驱动等都已经装好,表也建好了
出现的问题如下:
请各位大虾指点HTTP Status 500 - --------------------------------------------------------------------------------type Exception reportmessage description The server encountered an internal error () that prevented it from fulfilling this request.exception org.apache.jasper.JasperException: Exception in JSP: /mysql.jsp:129: <%
10: ResultSet RS = DBconn1.executeQuery("SELECT * FROM userinfo");
11: //userinfo为你的数据库表名
12: while (RS.next()) {
13: out.print("<h1>;" + RS.getString("username")+"+"+RS.getString("sex")+"+"+RS.getString("email")+"</h1>;");
14: //username、sex、email为字段名
15: }
Stacktrace:
org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:504)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:393)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:314)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:264)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
root cause java.lang.NullPointerException
org.apache.jsp.mysql_jsp._jspService(mysql_jsp.java:63)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:97)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:332)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:314)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:264)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
note The full stack trace of the root cause is available in the Apache Tomcat/5.5.17 logs.
--------------------------------------------------------------------------------Apache Tomcat/5.5.17
解决方案 »
免费领取超大流量手机卡,每月29元包185G流量+100分钟通话, 中国电信官方发货