How to convert Java Array/Collection to JSON array?

Google provides a library named org.json.JSONArray and, following is the maven dependency to add library to your project.

<dependency> <groupId>com.googlecode.json-simple</groupId> <artifactId>json-simple</artifactId> <version>1.1</version> </dependency>

The JSONArray class of the org.json package provides put() method. Using this method, you can populate the JSONArray object with the contents of the elements.

Example

import org.json.JSONArray; public class ArrayToJson { public static void main(String args[]) { String [] myArray = {"JavaFX", "HBase", "JOGL", "WebGL"}; JSONArray jsArray = new JSONArray(); for (int i = 0; i < myArray.length; i++) { jsArray.put(myArray[i]); } System.out.println(jsArray); } }

Output

["JavaFX","HBase","JOGL","WebGL"] 

In the same way you can pass a collection object to the constructor of the JSONArray class.

Example

import java.util.ArrayList; import org.json.JSONArray; public class ArrayToJson { public static void main(String args[]) { ArrayList <String> arrayList = new ArrayList<String>(); arrayList.add("JavaFX"); arrayList.add("HBase"); arrayList.add("JOGL"); arrayList.add("WebGL"); JSONArray jsArray2 = new JSONArray(arrayList); System.out.println(jsArray2); } }

Output

["JavaFX","HBase","JOGL","WebGL"]