Hey dude..
I'm ravi finished my b.tech this year and i'm from india hyderbad. I'm sending you a program which can impress your instructor. show this to him. And if you have any doubts call me on my mobile 09885565635
Arrays are first-class objects
Regardless of what type of array you’re working with, the array identifier is actually a handle to a true object that’s created on the heap. The heap object can be created either implicitly, as part of the array initialization syntax, or explicitly with a new expression. Part of the heap object (in fact, the only field or method you can access) is the read-only length member that tells you how many elements can be stored in that array object. The ‘ []’ syntax is the only other access that you have to the array object.
The following example shows the various ways that an array can be initialized, and how the array handles can be assigned to different array objects. It also shows that arrays of objects and arrays of primitives are almost identical in their use. The only difference is that arrays of objects hold handles while arrays of primitives hold the primitive values directly. (See page 97 if you have trouble executing this program.)
//: ArraySize.java
// Initialization & re-assignment of arrays
package c08;
class Weeble {} // A small mythical creature
public class ArraySize {
public static void main(String[] args) {
// Arrays of objects:
Weeble[] a; // Null handle
Weeble[] b = new Weeble[5]; // Null handles
Weeble[] c = new Weeble[4];
for(int i = 0; i < c.length; i++)
c[i] = new Weeble();
Weeble[] d = {
new Weeble(), new Weeble(), new Weeble()
};
// Compile error: variable a not initialized:
//!System.out.println("a.length=" + a.length);
System.out.println("b.length = " + b.length);
// The handles inside the array are
// automatically initialized to null:
for(int i = 0; i < b.length; i++)
System.out.println("b[" + i + "]=" + b[i]);
System.out.println("c.length = " + c.length);
System.out.println("d.length = " + d.length);
a = d;
System.out.println("a.length = " + a.length);
// Java 1.1 initialization syntax:
a = new Weeble[] {
new Weeble(), new Weeble()
};
System.out.println("a.length = " + a.length);
// Arrays of primitives:
int[] e; // Null handle
int[] f = new int[5];
int[] g = new int[4];
for(int i = 0; i < g.length; i++)
g[i] = i*i;
int[] h = { 11, 47, 93 };
// Compile error: variable e not initialized:
//!System.out.println("e.length=" + e.length);
System.out.println("f.length = " + f.length);
// The primitives inside the array are
// automatically initialized to zero:
for(int i = 0; i < f.length; i++)
System.out.println("f[" + i + "]=" + f[i]);
System.out.println("g.length = " + g.length);
System.out.println("h.length = " + h.length);
e = h;
System.out.println("e.length = " + e.length);
// Java 1.1 initialization syntax:
e = new int[] { 1, 2 };
System.out.println("e.length = " + e.length);
}
} ///:~
Here’s the output from the program:
b.length = 5
b[0]=null
b[1]=null
b[2]=null
b[3]=null
b[4]=null
c.length = 4
d.length = 3
a.length = 3
a.length = 2
f.length = 5
f[0]=0
f[1]=0
f[2]=0
f[3]=0
f[4]=0
g.length = 4
h.length = 3
e.length = 3
e.length = 2
Unsolved 
