碰到难问题了，程序报错了楞是改了两天没改过来

Question

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: com.mysql.jdbc.Driver
org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:460)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:355)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:329)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:265)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
java.lang.reflect.Method.invoke(Unknown Source)
org.apache.catalina.security.SecurityUtil$1.run(SecurityUtil.java:244)
java.security.AccessController.doPrivileged(Native Method)
javax.security.auth.Subject.doAsPrivileged(Unknown Source)
org.apache.catalina.security.SecurityUtil.execute(SecurityUtil.java:276)
org.apache.catalina.security.SecurityUtil.doAsPrivilege(SecurityUtil.java:162)
root cause javax.servlet.ServletException: com.mysql.jdbc.Driver
org.apache.jasper.runtime.PageContextImpl.doHandlePageException(PageContextImpl.java:841)
org.apache.jasper.runtime.PageContextImpl.access$1100(PageContextImpl.java:64)
org.apache.jasper.runtime.PageContextImpl$12.run(PageContextImpl.java:761)
java.security.AccessController.doPrivileged(Native Method)
org.apache.jasper.runtime.PageContextImpl.handlePageException(PageContextImpl.java:759)
org.apache.jsp.ShowArticleTree_jsp._jspService(ShowArticleTree_jsp.java:156)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:98)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:331)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:329)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:265)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
java.lang.reflect.Method.invoke(Unknown Source)
org.apache.catalina.security.SecurityUtil$1.run(SecurityUtil.java:244)
java.security.AccessController.doPrivileged(Native Method)
javax.security.auth.Subject.doAsPrivileged(Unknown Source)
org.apache.catalina.security.SecurityUtil.execute(SecurityUtil.java:276)
org.apache.catalina.security.SecurityUtil.doAsPrivilege(SecurityUtil.java:162)
root cause java.lang.ClassNotFoundException: com.mysql.jdbc.Driver
org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1362)
org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1208)
org.apache.jasper.servlet.JasperLoader.loadClass(JasperLoader.java:125)
org.apache.jasper.servlet.JasperLoader.loadClass(JasperLoader.java:63)
java.lang.ClassLoader.loadClassInternal(Unknown Source)
java.lang.Class.forName0(Native Method)
java.lang.Class.forName(Unknown Source)
org.apache.jsp.ShowArticleTree_jsp._jspService(ShowArticleTree_jsp.java:104)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:98)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:331)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:329)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:265)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
java.lang.reflect.Method.invoke(Unknown Source)
org.apache.catalina.security.SecurityUtil$1.run(SecurityUtil.java:244)
java.security.AccessController.doPrivileged(Native Method)
javax.security.auth.Subject.doAsPrivileged(Unknown Source)
org.apache.catalina.security.SecurityUtil.execute(SecurityUtil.java:276)
org.apache.catalina.security.SecurityUtil.doAsPrivilege(SecurityUtil.java:162)
note The full stack trace of the root cause is available in the Apache Tomcat/5.5.25 logs.
--------------------------------------------------------------------------------Apache Tomcat/5.5.25

Answer 1

下面ES的Exception2008-10-28 22:19:50 org.apache.catalina.core.AprLifecycleListener lifecycleEvent
信息: The Apache Tomcat Native library which allows optimal performance in production environments was not found on the java.library.path: C:\Program Files\Java\jre1.6.0_07\bin;.;C:\WINDOWS\Sun\Java\bin;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;C:\Program Files\Java\jdk1.5.0_04\bin;.;C:\Program Files\IDM Computer Solutions\UltraEdit-32
2008-10-28 22:19:50 org.apache.coyote.http11.Http11BaseProtocol init
信息: Initializing Coyote HTTP/1.1 on http-8080
2008-10-28 22:19:50 org.apache.catalina.startup.Catalina load
信息: Initialization processed in 735 ms
2008-10-28 22:19:50 org.apache.catalina.core.StandardService start
信息: Starting service Catalina
2008-10-28 22:19:50 org.apache.catalina.core.StandardEngine start
信息: Starting Servlet Engine: Apache Tomcat/5.5.25
2008-10-28 22:19:50 org.apache.catalina.core.StandardHost start
信息: XML validation disabled
2008-10-28 22:19:51 org.apache.coyote.http11.Http11BaseProtocol start
信息: Starting Coyote HTTP/1.1 on http-8080
2008-10-28 22:19:51 org.apache.jk.common.ChannelSocket init
信息: JK: ajp13 listening on /0.0.0.0:8009
2008-10-28 22:19:51 org.apache.jk.server.JkMain start
信息: Jk running ID=0 time=0/63  config=null
2008-10-28 22:19:51 org.apache.catalina.storeconfig.StoreLoader load
信息: Find registry server-registry.xml at classpath resource
2008-10-28 22:19:51 org.apache.catalina.startup.Catalina start
信息: Server startup in 1000 ms
2008-10-28 22:19:52 org.apache.catalina.core.StandardWrapperValve invoke
严重: Servlet.service() for servlet jsp threw exception
java.lang.ClassNotFoundException: com.mysql.jdbc.Driver
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1362)
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1208)
at org.apache.jasper.servlet.JasperLoader.loadClass(JasperLoader.java:125)
at org.apache.jasper.servlet.JasperLoader.loadClass(JasperLoader.java:63)
at java.lang.ClassLoader.loadClassInternal(Unknown Source)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Unknown Source)
at org.apache.jsp.ShowArticleTree_jsp._jspService(ShowArticleTree_jsp.java:104)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:98)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:331)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:329)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:265)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.apache.catalina.security.SecurityUtil$1.run(SecurityUtil.java:244)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAsPrivileged(Unknown Source)
at org.apache.catalina.security.SecurityUtil.execute(SecurityUtil.java:276)
at org.apache.catalina.security.SecurityUtil.doAsPrivilege(SecurityUtil.java:162)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:262)
at org.apache.catalina.core.ApplicationFilterChain.access$000(ApplicationFilterChain.java:52)
at org.apache.catalina.core.ApplicationFilterChain$1.run(ApplicationFilterChain.java:171)
at java.security.AccessController.doPrivileged(Native Method)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:167)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:213)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:174)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:117)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:108)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:151)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:874)
at org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.processConnection(Http11BaseProtocol.java:665)
at org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:528)
at org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerWorkerThread.java:81)
at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:689)
at java.lang.Thread.run(Unknown Source)

Answer 2

重发次代码<%@ page language="java" contentType="text/html; charset=gbk"
    pageEncoding="gbk"%>
<%@ page import="java.sql.*" %><%
String admin = (String)session.getAttribute("admin");
if(admin != null && admin.equals("true")) {
login = true;
}
%><%!
String str = "";
boolean login = false;
private void tree(Connection conn, int id, int level) {
Statement stmt = null;
ResultSet rs = null;
String preStr = "";
for(int i=0; i<level; i++) {
preStr += "----";
}
try {
stmt = conn.createStatement();
String sql = "select * from article where pid = " + id;
rs = stmt.executeQuery(sql);
String strLogin = "";

while(rs.next()) {
if(login) {
strLogin = "<td><a href='Delete.jsp?id=" + rs.getInt("id") + "&pid=" + rs.getInt("pid") + "'>删除</a>";
}
str += "<tr><td>" + rs.getInt("id") + "</td><td>" +
       preStr + "<a href='ShowArticleDetail.jsp?id=" + rs.getInt("id") + "'>" + 
       rs.getString("title") + "</a></td>" +
       strLogin +
       "</td></tr>";
if(rs.getInt("isleaf") != 0) {
tree(conn, rs.getInt("id"), level+1);
}
}
} catch (SQLException e) {
e.printStackTrace();
} finally {
try {
if(rs != null) {
rs.close();
rs = null;
}
if(stmt != null) {
stmt.close();
stmt = null;
}
} catch (SQLException e) {
e.printStackTrace();
}
}
}
%><%
Class.forName("com.mysql.jdbc.Driver");
String url = "jdbc:mysql://localhost/bbs?user=root&password=root";
Connection conn = DriverManager.getConnection(url);Statement stmt = conn.createStatement();
ResultSet rs = stmt.executeQuery("select * from article where pid = 0");
String strLogin = "";
while(rs.next()) {
if(login) {
strLogin = "<td><a href='Delete.jsp?id=" + rs.getInt("id") + "&pid=" + rs.getInt("pid") + "'>删除</a>";
}
str += "<tr><td>" + rs.getInt("id") + "</td><td>" +
        "<a href='ShowArticleDetail.jsp?id=" + rs.getInt("id") + "'>" + 
           rs.getString("title") + "</a></td>" +
           strLogin +
           "</td></tr>";
    if(rs.getInt("isleaf") != 0) {
    tree(conn, rs.getInt("id"), 1);
    }
}
rs.close();
stmt.close();
conn.close();
%><!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gbk">
<title>Insert title here</title>
</head>
<body>
<a href="Post.jsp">发表新帖</a>
<table border="1">
<%= str %>
<% 
str = ""; 
login = false;
%>
</table>
</body></html>

Answer 3

ClassNotFoundException~~明显没有找到com.mysql.jdbc.Driver这个驱动类~~你没有引入数据库的jar包吧？~~还有~~你做的这个东西我知道是什么，哈哈。

Answer 4

很明显的，找不到com.mysql.jdbc.Driver。把驱动包放到tomcat的lib目录下

Answer 5

java.lang.ClassNotFoundException: com.mysql.jdbc.Driver把你的 mysql.jar 放到 tomcat/shared/lib 目录下面去就行了

Answer 6

我当然引进去了啊！
我把Driver引到tomcat/的lib目录下了！

Answer 7

如果没有设置好系统变量，可能会出现这种问题简单点可以把jar包放在工程的web-inf的lib下

Answer 8

你编译时的path和运行是的path是否一样

Answer 9

1、把驱动放在项目和tomcat的对应lib下。
2、看看环境变量设置有没有问题

Answer 10

可能是你放的地方不对了,放到webapps/自己的项目名/web-inf/lib下边就好了