将JSON导入Eclipse项目

Question

I'm an aspiring Java programmer looking to use JSON in a project. I was following a programming tutorial (from a book) which asked me to import JSON into my project by using the following line:

import com.google.appengine.repackaged.org.json.JSONArray; 

But this produced an error, so I replaced it with this line:

import org.json.JSONArray;

This also produces a (different) error:

The import org.json cannot be resolved

I think the problem is that I don't actually have the JSON library in my Eclipse workspace. How can I do this, so I can use the JSONArray? I found the website for JSON, but am not sure what to download or how or where to install it:

http://json.org/java/

Answer 1

Download the ZIP file from this URL and extract it to get the Jar. Add the Jar to your build path. To check the available classes in this Jar use this URL .

To Add this Jar to your build path Right click the Project > Build Path > Configure build path> Select Libraries tab > Click Add External Libraries > Select the Jar file Download

I hope this will solve your problem

Answer 2

You should take the json implementation from here : http://code.google.com/p/json-simple/ .

• Download the *.jar
• Add it to the classpath (right-click on the project, Properties->Libraries and add new JAR.)

Answer 3

Download json from java2s website then include in your project. In your class add these package java_basic;

import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.util.Iterator;

import org.json.simple.JSONArray;
import org.json.simple.JSONObject;
import org.json.simple.parser.JSONParser;
import org.json.simple.parser.ParseException;

Answer 4

It still doesn't work for me, but at least I don't get the JSON library error anymore. Copy json-1.5.jar into the main folder from here link , not into the library one and then replace every import com.google.appengine.repackaged.org.json.JSONArray; with import org.json.JSONArray; like you pointed out. Still I get the following warning every time I try to access the Datastore:

com.google.appengine.tools.development.LocalResourceFileServlet doGet
WARNING: No file found for: /favicon.ico

Did you manage to make the code work in the end?

Answer 5

在linux pip上安装library_that_you_need同样在Help / Eclipse MarketPlace上，我为Eclipse 7添加PyDev IDE，所以当我启动一个新项目时，我创建了文件/ New Project / Pydev Project

Answer 6

The link of accepted answer is old and can cause warnings with generics use,

You should download latest jar from JSON-java github site

Add jar to Java build Path

In existing project in Order and Export tab move the new jar, as json-20180813.jar , as the first (or above other dependencies with JSONObject )

Answer 7

Download java-json.jar from here, which contains org.json.JSONArray

http://www.java2s.com/Code/JarDownload/java/java-json.jar.zip

nzip and add to your project's library: Project > Build Path > Configure build path> Select Library tab > Add External Libraries > Select the java-json.jar file.

Answer 8

Download the json jar from here . This will solve your problem.