Re: Bitwise (flags) enums: how to compare?

Jeffrey Schwab <>
Tue, 03 Oct 2006 00:05:37 GMT
z-man wrote:

I tried hard to find on google some reference about bitwise (flags)
native enums in Java 1.5, without success.
What's the proper way to define and compare bitwise enums (see below)?

Thank you!

public enum MyFlags

 private final int bit;

 MyFlags(int bit)
  this.bit = bit;

 public int getBit()
  return bit;


MyFlags flags = FlagA + FlagB;
// Question: Is this bitwise comparison legal?
if((flags & FlagB) == FlagB)
 System.out.println("Missed (should not happen).");

java.util.EnumSet may be what you want.

// cljp\
package cljp;

public enum MyFlags {

// cljp\
package cljp;

import java.util.EnumSet;
import static cljp.MyFlags.*;

public class Main {

     public static void main(String[] args) {

         EnumSet<MyFlags> flags = EnumSet.of(FlagA, FlagB);

         if(flags.contains(FlagB)) {
         } else {
             System.out.println("Missed (should not happen).");

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