Showing buttons based on a message received by arduino

Processing Electronics (Arduino, etc.)
7

Just a small follow up question .

This is not giving the desired response.

void receive( byte[] data, String ip, int port ) {  
  data = subset(data, 0, data.length);
  message = new String( data );
if(message == "ack_on") received = 1;
  if(message == "ack_off") received = 0;
}

But this is working as I wanted. What is the difference between the two? It should have been same in my opinion.

void receive( byte[] data, String ip, int port ) {  
  data = subset(data, 0, data.length);
  message = new String( data );
received = "ack_on".equals(message);
}

I will put the full code again just for clarity. The commented portion is the not working portion. I had to modify my code a bit to make it look a bit decent

import controlP5.*; //import ControlP5 library
import hypermedia.net.*;
UDP udp;  
ControlP5 cp5; 
PImage led_red, led_green, led_white;
PFont font;
String message;
int received = 2;
Boolean breceived;

void setup() { 
  size(300, 300);    

  cp5 = new ControlP5(this);
  font = createFont("Ubuntu Mono Bold", 15);   
  led_red = loadImage("red.png");
  led_green = loadImage("green.png");
  led_white = loadImage("white.png");
  udp = new UDP(this, 6124);
  udp.listen(true);

  // Add the buttons to GUI
  cp5.addButton("ON")  //The button
    .setPosition(50, 60)  //x and y coordinates of upper left corner of button
    .setSize(70, 50)      //(width, height)
    ;
  cp5.addButton("OFF")  //The button
    .setPosition(50, 120)  //x and y coordinates of upper left corner of button
    .setSize(70, 50)      //(width, height)
    ;
}

void draw() {  //Same as loop in arduino

  background(150, 150, 150);
  textFont(font); 
  text("Remote Control Interface", 70, 30);  
  image(led_white, 140, 60);
  image(led_white, 140, 120);
  if (received == 1) {
    image(led_green, 140, 60);
    text("Ack for ON", 186, 88);
  }
  if (received == 0) {
    image(led_red, 140, 120);
    text("Ack for OFF", 186, 148);
  }
}


void ON() {

  send("ON");
}

void OFF() {

  send("OFF");
}

void receive( byte[] data, String ip, int port ) {  // <-- extended handler

  data = subset(data, 0, data.length);
  message = new String( data );

  //if (message == "ack_on") received = 1;
  //if (message == "ack_off") received = 0;
  breceived = "ack_on".equals(message);
  if(breceived) received =1;
  else if(!breceived) received =0;
  println( "receive: \""+message+"\" from "+ip+" on port "+port );
}

void send(String message) {

  //String message  = "ON";  // the message to send
  String ip       = "localhost";  // the remote IP address
  int port        = 6123;    // the destination port

  udp.send( message, ip, port );
}

ack