For Loops

When you know exactly how many times you want to loop through a block of code, use a for loop instead of a while loop:

for (initialization; condition; iteration) {
  // code block to be executed
}

• initialization is executed (one time) before the execution of the code block.
• condition (as the name implies) defines the condition for executing the code block.
• iteration is executed (every time) after the code block has been executed.

The example below will print the numbers 0 to 4:

for (int i = 0; i < 5; i++) {
  System.out.println(i);
}

• initialization sets a variable before the loop starts (int i = 0).
• condition defines the condition for the loop to run (i must be less than 5). If the condition is true, the loop will start over again, if it is false, the loop will end.
• iteration increases a value (i++) each time the code block in the loop has been executed.

This example will only print even values between 0 and 10:

for (int i = 0; i <= 10; i = i + 2) {
  System.out.println(i);
}