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toString Clarification

Mitch Krah
Ranch Hand

Joined: Sep 06, 2004
Posts: 41
Can someone provide clarification of the toString method and overriding it in classes to print "meaningful" information? I have been asked to implement the toString method in classes but can only find a paragraph on this method in 2 different books. Any additional/practicle information would be appreciated.

Thank you,
Jeanne Boyarsky
author & internet detective

Joined: May 26, 2003
Posts: 32649

By default the toString() method outputs a hash representing the memory address. Often, we overwrite this to contain useful information about the state of the object (such as the values of it's fields.) As an example,

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Mitch Krah
Ranch Hand

Joined: Sep 06, 2004
Posts: 41
Thank you.

And then, how do you call the toString from another class?

Mike Gershman
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Joined: Mar 13, 2004
Posts: 1272
System.out.println( myObject );
System.out.println( myObject.toString() );

It makes no never mind.

Mike Gershman
SCJP 1.4, SCWCD in process
David Harkness
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Joined: Aug 07, 2003
Posts: 1646
Appending an object reference to a String using the + operator will call toStrnig() on the reference (or append "null" if it's null) for you.
I agree. Here's the link:
subject: toString Clarification
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