com.google.common.base
Class Objects

java.lang.Object
  extended by com.google.common.base.Objects

public final class Objects
extends Object

Helper functions that can operate on any Object.

Since:
2010.01.04 stable (imported from Google Collections Library)
Author:
Laurence Gonsalves

Nested Class Summary
static class Objects.ToStringHelper
          Support class for toStringHelper(java.lang.Object).
 
Method Summary
static boolean equal(Object a, Object b)
          Determines whether two possibly-null objects are equal.
static int hashCode(Object... objects)
          Generates a hash code for multiple values.
static Objects.ToStringHelper toStringHelper(Object object)
          Creates an instance of Objects.ToStringHelper.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Method Detail

equal

public static boolean equal(@Nullable
                            Object a,
                            @Nullable
                            Object b)
Determines whether two possibly-null objects are equal. Returns:

This assumes that any non-null objects passed to this function conform to the equals() contract.


hashCode

public static int hashCode(Object... objects)
Generates a hash code for multiple values. The hash code is generated by calling Arrays.hashCode(Object[]).

This is useful for implementing Object.hashCode(). For example, in an object that has three properties, x, y, and z, one could write:

 public int hashCode() {
   return Objects.hashCode(getX(), getY(), getZ());
 }
Warning: When a single object is supplied, the returned hash code does not equal the hash code of that object.


toStringHelper

public static Objects.ToStringHelper toStringHelper(Object object)
Creates an instance of Objects.ToStringHelper.

This is helpful for implementing Object.toString(). For example, in an object that contains two member variables, x, and y, one could write:

   
   public class ClassName {
     public String toString() {
       return Objects.toStringHelper(this)
           .add("x", x)
           .add("y", y)
           .toString();
     }
   }
 
Assuming the values of x and y are 1 and 2, this code snippet returns the string "ClassName{x=1, y=2}".

Since:
2010.01.04 tentative