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Used of toString

Armel Moukoss

Joined: Mar 28, 2007
Posts: 14

I don't really understand how the toString method is used in the code below :

One of the possible result :

Initial State: [k, q, i, j, f, V, J, S, c, v, u', U, C, z, I, y, d, H, X, e]
Sorted: [C, H, I, J, S, U, V, X, c, d, e, f, i, j, k, q, u', v, y, z]
Reversed: [z, y, v, u', q, k, j, i, f, e, d, c, X, V, U, S, J, I, H, C]

I don't see any place where the toString method is called. But if i put it in commentary the result is not the same. Can someone help me, please ? thank you.

Ps : I take the code on the cd of the book "complete java 2 certification", in solution of the chapter 8.
Kaydell Leavitt
Ranch Hand

Joined: Nov 18, 2006
Posts: 689

In this code example, I believe that the toString() method is called by the following code:

The first parameter to println() is a String, so the "+" sign means string concatenation (not addition) and so the vec variable will be converted to a String, using its toString() method, since it is in a String context. The Vector must, in turn, call toString() for each element in the Vector.

[ May 28, 2007: Message edited by: Kaydell Leavitt ]
Nik Arora
Ranch Hand

Joined: Apr 26, 2007
Posts: 652
Its called when System.out.println() is invoked. Even you can override to print in the format you want.

Scjp 1.5
Deepak Bala

Joined: Feb 24, 2006
Posts: 6662

Heres a simple example

Try doing this

System.out.println(new Test());

You should see the custom definition of the class on your console instead of its memory location.

SCJP 6 articles - SCJP 5/6 mock exams - More SCJP Mocks
Armel Moukoss

Joined: Mar 28, 2007
Posts: 14

Just to thank you very much guys for yours answers.

I agree. Here's the link:
subject: Used of toString
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