NoClassDefFoundError,问题解决

来源：互联网发布：jsp javabean 获取数组编辑：程序博客网时间：2024/05/17 12:56

今天写了个调用.bat的程序时，出现了个低级的错，总结一下；前台是用JSP写，后台是写个SERVLET，

后台JAVA代码如下

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package com.vogoal.util;

import java.io.BufferedReader;
import java.io.InputStreamReader;

public class RunBat {

     public static void main(String[] args) {
        try {
            Process process = Runtime.getRuntime().exec("C:\\\\Program Files\\tomcat6\\webapps\\ROOT\\run.bat");
            BufferedReader read = new BufferedReader(new InputStreamReader(process.getInputStream()));
            String str = null;
            while ((str = read.readLine()) != null) {
                System.out.println(str);
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

}

--------------------------------------------------------

前台JSP如下：

--------------------------------------------------------

<%@ page    contentType="text/html; charset=GBK" %>
<%@ page    import="com.vogoal.util.RunBat" %>

<html>
<head>
<title>Run bat to start testing</title>
<meta http-equiv="Content-Type" content="text/html; charset=GBK">
</head>
<body>
<%
   RunBat.main(null);

%>
</body>
</html>
--------------------------------------------------------

之前RunBat.main(null);写成了

RunBat rb = new RunBat();

rb.main(null);

结果报错了，NoClassDefFoundError，之后想想才知道，可能main()构造函数的原因，嘿嘿！

另外说一下，web.xml里面多个servlet配置，其实很简单，就是简单的添加就可以，例如：

<servlet>
<servlet-name>JspFileUpload</servlet-name>
<display-name>JspFileUpload</display-name>
<description>A test Servlet</description>
<servlet-class>classes.com.vogoal.util.JspFileUpload</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>JspFileUpload</servlet-name>
<url-pattern>/JspFileUpload</url-pattern>
</servlet-mapping>


<servlet>
<servlet-name>RunBat</servlet-name>
<display-name>RunBat</display-name>
<description>Start Servlet</description>
<servlet-class>classes.com.vogoal.util.RunBat</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>RunBat</servlet-name>
<url-pattern>/RunBat</url-pattern>
</servlet-mapping>