Probably your simple json.jar file isn't in your classpath.
Answer from Arun Manivannan on Stack OverflowProbably your simple json.jar file isn't in your classpath.
I was facing same issue in my Spring Integration project. I added below JSON dependencies in pom.xml file. It works for me.
<dependency>
<groupId>org.json</groupId>
<artifactId>json</artifactId>
<version>20090211</version>
</dependency>
A list of versions can be found here: https://mvnrepository.com/artifact/org.json/json
If you are using Json-simple, use the below maven dependency.
<dependency>
<groupId>com.googlecode.json-simple</groupId>
<artifactId>json-simple</artifactId>
<version>1.1</version>
</dependency>
Link: https://mvnrepository.com/artifact/com.googlecode.json-simple/json-simple/1.1
If you are using maven, you can add the following dependency
<dependency>
<groupId>javax</groupId>
<artifactId>javaee-api</artifactId>
<version>7.0</version>
</dependency>
you can also download the artefact manually here
http://central.maven.org/maven2/javax/javaee-api/7.0/javaee-api-7.0.jar
For Gradle, use
compile group: 'javax', name: 'javaee-api', version: '7.0'
The site https://mvnrepository.com shows you the different dependencies for different build systems.
Please note that this is only one possible dependency. You can certainly find smaller dependencies, which only contain the classes you want. Simply search for it on google or mavencentral.
If you download the JSON jar specified, and list its contents (e.g. with jar tf), it does not contain the org.json.simple package.
So the problem is simply that you need another jar.
EDIT:
I don't know if this is the intent, but an educated guess: if you add this dependency to build.gradle:
compile 'com.googlecode.json-simple:json-simple:1.1.1'
and these imports:
import org.json.simple.parser.*;
// import org.json.simple.*;
import org.json.*;
then the example compiles (for me).
Adding this to my build.gradle file works:
implementation 'com.googlecode.json-simple:json-simple:1.1.1'