Break

A break statement exits a loop before an entry condition fails. For example, in this variation on the CountWheat program an error message is printed, and you break out of the for loop if j becomes negative.

class CountWheat  {

  public static void main (String args[]) {
  
    int total = 0;

    for (int square=1, grains = 1; square <= 64; square++) {
      grains *= 2;
      if (grains <= 0) {
        System.out.println("Error: Overflow");
        break;
      }
      total += grains;
      System.out.print(total + "\t  ");
      if (square % 4 == 0) System.out.println();
    } 
    System.out.println("All done!");

  }

}

Here's the output:

% javac CountWheat.java
% java CountWheat
2            6           14              30
62           126         254             510
1022         2046        4094            8190
16382        32766       65534           131070
262142       524286      1048574         2097150
4194302      8388606     16777214        33554430
67108862     134217726   268435454       536870910
1073741822   2147483646      Error: Overflow
All done!

The most common use of break is in switch statements.


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Copyright 1997, 1999, 2004 Elliotte Rusty Harold
elharo@metalab.unc.edu
Last Modified December 16, 2004