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Name: rmT116609 Date: 11/16/2001


java version "1.4.0-beta3"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.0-beta3-b84)
Java HotSpot(TM) Client VM (build 1.4.0-beta3-b84, mixed mode)


Collections.binarySearch(List list, Object key, Comparator c)
throws a NullPointerException when null is given as Comparator.

The docs states that giving null as a Comparator is perfectly ok, and works as expected in 1.3 but not in 1.4-beta3.


public class BinSearchBug {
    
    
    static class Item implements java.lang.Comparable {
        String name;
        Item( String name ) {
            this.name = name;
        }
        public int compareTo( Object o ) {
            return name.compareTo( ((Item) o).name );
        }
    }

    public static void main (String args[]) {
        java.util.List list = new java.util.ArrayList();
        list.add( new Item( "item" ));
        
        // Works
        System.err.print( "binary search without comparator... " );
        java.util.Collections.binarySearch( list, new Item( "item_1" ));
        System.err.println( "ok" );
        
        // Throws a NullPointerException
        System.err.print( "binary search with null comparator... " );
        java.util.Collections.binarySearch( list, new Item( "item_1" ), null );
        System.err.println( "ok" );
    }

}

In JDK1.3.1_01:
--------------------------
C:\> java BinSearchBug
binary search without comparator... ok
binary search with null comparator... ok

In JDK1.4.0-beta3:
--------------------------
binary search without comparator... ok
binary search with null comparator... Exception in thread "main" java.lang.NullPointerException
        at java.util.Collections.indexedBinarySearch(Collections.java:311)
        at java.util.Collections.binarySearch(Collections.java:299)
        at BinSearchBug.main(BinSearchBug.java:25)
(Review ID: 135806)
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