email me at borlaj@portlandschools.org
notes previous (09/07/06) submit the dump links  
 

Loops

see here for examples

Just like in Alice or AppInventor it is often useful to use loops to repeat code statements. Even if something is being repeated just 2x, it is useful to use loops because:

  • Makes coding faster
  • Better readability
  • If you make a change to your code in the loop, you change it in one place.

The two main types of loops are

  • while
  • for

while loops

 

while (condition is true)

{
	do this
}

for example

int i=0;

while (i<10)
{
	System.out.println(i);
	i++;
}

for loops

are in the format: for (this counter variable staring here, while this condition met, do this to the counter)

 

for (int i=0; i<10; i++)
{
	System.out.println("We are at" + i);
}

this would repeat the inside 10 times (while i was 0 through 9)

 

Exiting (not used all that often, just reference)

To exit the current loop, you use the statement:

break;

 

Lets create these methods: HERE IS STARTER CODE

  • public void printCODFor() that will print I played COD all night 50 times. Do this with a for loop
  • public void printSpencerWhile() that will print I will not shoplift at Spencer Gifts 50 times. Do this with a while loop
  • advanced
    1. public void printFibonacci(int values) that will print x fibonacci numbers