Java Iteration

• Iteration
  • while loops
    • Loop
    • Syntax
    • Infinite loop
    • return statements
  • for loops
    • Syntax
    • Off-By-One Error

Iteration

Iteration: Repeatedly do something.

while loops

Loop

Loop executes instructions repeatedly while a condition is true.

Syntax

while( condition )
{
  //statements
}

Infinite loop

• keep going forever
• condition always true

return statements

a return statement inside an iteration statement will halt the loop and exit the method or constructor

for loops

Syntax

for( initialization, condition, update )
{
  <statements>  //body of loop
}

WE MUST DECLARE THE TYPE OF THE VARIABLE MENTIONED IN INITIALIZATION!!!
This declaration can be ahead of the loop.

Off-By-One Error

check whether the code executes exactly the same times as we want

For instance, this following code have an Off-By-One Error:

String str = "for loops";
for(int i = 1, i < str.length(), i++);
System.out.print(str.substring(i,i+1));

The correct one should be:

String str = "for loops";
for(int i= 0, i < str.length(), i++);
System.out.print(str.substring(i,i+1))

And that’s all for this post!