The java.util.Objects comes with nearly a dozen of very simple static utility methods. But at least I don't see any big usage of these methods ;), since most of them are available (in some other form) in the older JDK versions.
In the following we will see some sample code for 2 of the newly introduced methods.
You can have a look at the rest of them here.
equals(Object a, Object b) - Returns true if the arguments are equal to each other and false otherwise.
hashCode(Object o) - Returns the hash code of a non-null argument and 0 for a null argument.
Integer obj1 = new Integer( 1 ); Integer obj2 = new Integer( 1 ); Integer objNull = null; System.out.println( Objects.equals( obj1, obj2 ) ); System.out.println( Objects.equals( obj1, objNull ) );
prints the following...
true false
One can get the hash code of an object using (Line 1) Objects.hashCode(Object o). But i don't know what is its purpose since we already have Object.hashCode() that does exactly the same(Line 2).
Integer obj5 = new Integer( 5 ); //(Line 1)new one System.out.println( Objects.hashCode( obj5 ) ); //(Line 2)this is the already existing method System.out.println( obj5.hashCode() );Prints the following
5 5
Let us see whether the Java guys add some more utility methods before the release of JDK7.
Stay tuned.
No comments:
Post a Comment