Add json jar to your classpath

or use java -classpath json.jar ClassName

Or add this to your maven pom.xml depedencies:

<dependency>
    <groupId>org.json</groupId>
    <artifactId>json</artifactId>
    <version>20090211</version>
</dependency>

Have you considered using Maven? for instance, if you wanted a JAR to pars JSON you could just include...

http://mvnrepository.com/artifact/org.codehaus.jackson/jackson-core-asl/1.9.6

<dependency>
    <groupId>org.codehaus.jackson</groupId>
    <artifactId>jackson-core-asl</artifactId>
    <version>1.9.6</version>
</dependency>

in a pom.xml, this will give you the jar for JSON.

Or better yet, use the org.json one...

http://mvnrepository.com/artifact/org.json/json

<dependency>
    <groupId>org.json</groupId>
    <artifactId>json</artifactId>
    <version>20090211</version>
</dependency>