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Objects in Arraylist

 
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Hi everybody!

I want to make function witch will crate an object and put him in Arraylist, so I could later acces to those object, so can I do this



but, would I loose acces to objects in Arraylist when my referece (o) is associated with new Object? Remeber,I want to have n same object with diferent values in Arraylist.

kind regardes
 
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Hi,

you could use get method to obtain the reference again

 
Marko Debac
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Ok, but if I assign on some object his name with setName("John"), and latter I want to delete this object from the list, could I do this

 
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Hi cowboys,

in your methods everything is local. You cannot access any of your variables from outside, so whatever has been done in your methods evaporates after they have been called.

Perhaps use the list as a member of your class. And also you should have the object to be added, deleted or whatsoever as a paramater in the signature of your methods.


Yours,
Bu.
 
Marko Debac
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Hi,

I have a List in my class, and I get to her by getList(), and how could I tell the function with parameter witch object I want delete cose I must search for him first by getName("John")?

regards
 
Burkhard Hassel
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Hi Marco,

you could pass a String to you method as:




Otherwise, the function only deletes Johns.

By the way, I just did it for explanation, but you should not provide pseudocode here. If you do, nobody will know really what your problem is.
Your code for example can never compile, as Object simply does not have a method get().


Yours,
Bu.
 
Marko Debac
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Hi again,

You ment something like this:



would I now delete object with specific name from the list?

Thnx
 
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Your method has a few bugs.
Finally in Java the convention is to begin method names with lower case letters, so your method would be called deleteObject(). This convention is obviously not enforced by the compiler, but it does make the intention of your code clearer for others reading it.
[ October 15, 2006: Message edited by: Garrett Rowe ]
 
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Also read up on Maps. They store and retrieve objects by keys. They key can be any other object but is often a string. If you always fetch things by the same field, in this case the field is name, a Map will do the job nicely.
 
Marko Debac
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Hi to all!

..or I can do this

 
Yeah, but is it art? What do you think tiny ad?
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