Check out example codes for "java while". It will help you in understanding the concepts better.

Code Example 1

//runs as long as the condition is true
while(condition){
//do what you want in here
doStuff()
}

Code Example 2

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

Code Example 3

while(i < 5) //while i < 5 stay in the loop
{
  System.out.print(i);
  i++;
}
/*
	do someting
	change variable
    call methods
    etc...
*/

Code Example 4

do {
	// loop content
} while (/* condition */);

Code Example 5

while (condition) {
  // code block to be executed
}

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