/* package whatever; // don't place package name! */
 
import java.util.*;
import java.lang.*;
import java.io.*;
 
/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
		String testData="String Notify : {\"id\": \"1234\", \"transactionId\": \"TR-001\", \"timestamp\": \"1575445871\"} with result success";
		int jsonStart=testData.indexOf('{');
		int jsonEnd=testData.lastIndexOf('}')+1;
		if(jsonStart>=0 && jsonEnd>jsonStart) {
			String jsonPart=testData.substring(jsonStart,jsonEnd);
			System.out.println(jsonPart);
		}
	}
}

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