Parse JSON string in Java

Question

I'm trying to parse a JSON string in Java but I cant figure out how! I'm using lib-JSON right now:

import net.sf.json.*;

.

String jsonStr = "{'string':'JSON', 'integer': 1, 'double': 2.0, 'boolean': true}";
JSONObject jsonObj = (JSONObject) JSONSerializer.toJSON(jsonStr); // this line crashes

I get no compilation errors but when i run the program it says:

Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/commons/lang/exception/NestableRuntimeException
 at java.lang.ClassLoader.defineClass1(Native Method)
 at java.lang.ClassLoader.defineClassCond(ClassLoader.java:631)
 at java.lang.ClassLoader.defineClass(ClassLoader.java:615)
 at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:141)
 at java.net.URLClassLoader.defineClass(URLClassLoader.java:283)
 at java.net.URLClassLoader.access000ドル(URLClassLoader.java:58)
 at java.net.URLClassLoader1ドル.run(URLClassLoader.java:197)
 at java.security.AccessController.doPrivileged(Native Method)
 at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
 at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
 at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
 at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
 at ircbot.plugins.SiteTitle.<init>(SiteTitle.java:28)
 at ircbot.Main.main(Main.java:10)
Caused by: java.lang.ClassNotFoundException: org.apache.commons.lang.exception.NestableRuntimeException
 at java.net.URLClassLoader1ドル.run(URLClassLoader.java:202)
 at java.security.AccessController.doPrivileged(Native Method)
 at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
 at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
 at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
 at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
 ... 14 more
Java Result: 1
BUILD SUCCESSFUL (total time: 0 seconds)

It sounds like I'm missing some dependencies, but I don't know how to find out if or which!

Thanks in advance!

Answer 1

It seems you have not imported need jar file for class "org.apache.commons.lang.exception.NestableRuntimeException"

There are many classes that we use in our Java program and which don't come with Java. So we need to put Suitable Jar file for them.

• oskob: But I do have the apache commons lib! But now when I look inside it there is no subpackage lang.exception... I do find org.apache.commons.lang3, but still no exceptions!
• gprathour: @oskob try this link, if you search then will see this jar file contains the class you are looking for. java2s.com/Code/Jar/ABC/Downloadcommonslang24jar.htm
• oskob: That link looks broken :P however, it seems i used the wrong version, i tried 2.x instead of 3.x and it worked!

Answer 2

I recomend grepcode Just enter the class name and you get a list of the known versions of jars

Example: here

Answer 3

You are missing jar file. No jar file in your class path. 

see this Reading JSON file error

Answer 4

org/apache/commons/lang -> http://commons.apache.org/lang/ Basically, use Google and get the respective jar.

Answer 5

Your JSON String also not valid, This the valid JSON,

{"string": "JSON","integer": "1","double": "2.0","boolean": "true" }

Answer 6

These are the dependencies -

1. jakarta commons-lang 2.5
2. jakarta commons-beanutils 1.8.0
3. jakarta commons-collections 3.2.1
4. jakarta commons-logging 1.1.1
5. ezmorph 1.0.6

are you sure you added all of them in your classpath.

• oskob: Is there an easy way to find these dependencies? It seems like a lot of libs for just JSON parsing :S
• Rifat: @oskob I personally use google-gson code.google.com/p/google-gson . Apache libs are like this, lots of dependencies.