Introduction to Programming

if 

The simple if statement allows executing a certain statement or block conditionally, only when the result of the expression evaluation is true:

if(booelan expression){  //do something} 

Here are a few examples:

if(true) System.out.println("true");    //1: trueif(false) System.out.println("false");  //2:int x = 1, y = 5;if(x > y) System.out.println("x > y");  //3:if(x < y) System.out.println("x < y");  //4: x < yif((x + 5) > y) {                       //5: x + 5 > y  System.out.println("x + 5 > y");      x = y;}if(x == y){                             //6: x == y  System.out.println("x == y");       }

Statement 1 prints true. Statements 2 and 3 print nothing. Statement 4 prints x < y. Statement 5 prints x + 5 > y. We used braces to create a block because we wanted the x = y statement to be executed only ...