java - Servlet 中的 JSONObject ClassNotFoundException

Question

我想在我的 Servlet 中创建一个 JSONObject:

import org.json.JSONObject;
[...]    
Map<String, String> data1 = new HashMap<String, String>();
Map<String, String> data2 = new HashMap<String, String>();
data1.put("name", "f1");
data1.put("key", "aa1");
data1.put("value", "21");
data2.put("name", "f2");
data2.put("key", "aa2");
data2.put("value", "22");

JSONObject json1 = new JSONObject(data1);

但是当我运行我的应用程序时，出现异常:

exception 
javax.servlet.ServletException: Servlet execution threw an exception    

root cause 
java.lang.NoClassDefFoundError: org/json/JSONObject
    servlet.LoginServlet.doPost(LoginServlet.java:71)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:643)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:723)


root cause 
java.lang.ClassNotFoundException: org.json.JSONObject
    org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1680)
    org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1526)
    servlet.LoginServlet.doPost(LoginServlet.java:71)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:643)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:723)

我使用了以下 json 资源: https://code.google.com/p/org-json-java/downloads/list

Answer 1

Download java-json jar file and add it into class path.

For Classpath reference: Right click on project in eclipse -> Buildpath -> Configure Build path -> Java Build Path (left Pane) -> Libraries(Tab) -> Add External Jars -> Select your jar and select ok.