PRINTING OUT A JAVA ARRAY WITH JAVA.UTIL.ARRAYS
What do you do if you print an array out to a log or debug line, but 
the Java array Object's toString() method is useless. Use the 
java.util.Arrays class instead.

The following code outputs something like: [Ljava.lang.Object;@14af67
Object[] objs = new Object[] {"abby", "bob", "chris"}; 
System.out.println( objs );

Instead do:

import java.util.Arrays; 
 
.... 
 
Object[] objs = new Object[] {"abby", "bob", "chris"}; 
System.out.println( Arrays.asList(objs) );
This uses the java.util.List's better toString:
[abby, bob, chris]

Note that the asList method returns an immutable List, so entries are 
not allowed to be changed.

The Arrays class contains other useful methods. It can tell you if a 
pair of arrays are equal, which means they contain equal values, via 
its static equals(Object[], Object[]) method. The method is overridden 
numerous times to account for arrays of the Java primitives, int, char 
etc.

You can do a search on an array using the binary search algorithm. As 
before, there are overridden versions for each Java primitive as well 
as an extra method that takes a Comparator.

There is also a fill method that allows you to set all the array values 
to a single value, optionally specifying a start and end index if only 
a slice of the array is wished to be a default value.

For example:

    // initialise all 55 elements 
    int[] percentages = new int[] { 100, 100, 100, 100, ... 100 };
can be more easily written as:
import java.util.Arrays; 
 
.... 
 
    int[] percentages = new int[55]; 
    Arrays.fill( percentages, 100 );

Finally you can sort an array or a slice of an array, providing an 
optional Comparator for Object arrays. The sorting algorithm is stable 
so Objects that are 'equal' will not get jumbled around.

The java.util.Arrays class is a powerful provider of standard 
functionality, which often gets overlooked in favor of its sibling, 
java.util.Collections. Also of note is the java.lang.System.arraycopy 
method. It provides a high-performance way to copy values from one 
array to another. 

REFERENCES:

JAVA.UTIL.ARRAYS JAVADOC
http://java.sun.com/j2se/1.3/docs/api/java/util/Arrays.html 

JAVA.LANG.SYSTEM#ARRAYCOPY JAVADOC
http://java.sun.com/j2se/1.3/docs/api/java/lang/System.html#arraycopy(java.lang.Object,int, 
java.la

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