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please help me out (about "composition")

lang lang
Greenhorn

Joined: Nov 01, 2003
Posts: 8

what "composition "mean?
thank you!!
[ Jess added UBB [code] tags to preserve whitespace, check 'em out! ]
[ November 01, 2003: Message edited by: Jessica Sant ]
Jessica Sant
Sheriff

Joined: Oct 17, 2001
Posts: 4313

Ok -- so I adjusted your code a bit (see my comments)

The WaterSource.toString() method is used to override Object.toString() method that every class inherits. This method is invoked whenever you try to print an objedct. So on the line I marked with **** the WaterSource.toString() method is invoked so that the contents of WaterSource is displayed however you choose.
When I run this code as you see it, I get the following output:
WaterSource()
value1 = some Value
source = pipes

Try commenting out the WaterSource.toString() method, so that the default toString() is used, and you get this (the exact value you get for source will vary from execution to execution:
WaterSource()
value1 = some Value
source = WaterSource@1a16869

Does that help?
[ November 01, 2003: Message edited by: Jessica Sant ]

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