Code to use when you want to process Json with only standard library in Java

package script;

import javax.script.ScriptEngine;
import javax.script.ScriptEngineManager;
import javax.script.ScriptException;

public class JsonUtil {

	public static Object get(String json, String code) {
		// Get the JavaScript engine
		ScriptEngineManager manager = new ScriptEngineManager();
		ScriptEngine engine = manager.getEngineByName("JavaScript");
		String script = "var obj = " + json + ";";
		try {
			engine.eval(script);
			{
				return engine.eval("obj." + code);
			}
		} catch (ScriptException e) {
			e.printStackTrace();
			return null;
		}
	}
	//How to use/ How to use
	public static void main(String[] args) {
		String json = "{'test':'this is test','test2':{'test3':'value3'}}";

		{
			Object value = JsonUtil.get(json, "test");
			System.out.println(value);
		}
		{
			Object value = JsonUtil.get(json, "test2.test3");
			System.out.println(value);
		}

	}

}

this is test
value3

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