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Reuse Object

 
Ranch Hand
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Hi All,
I have one requirement which can be explained by the following code snippet.
ArrayList v1= new ArrayList();
StringBuffer sb= new StringBuffer();

for(int i=0;i<10;i++)
{
//sb= new StringBuffer();
sb.append(i);
v1.add(sb);
}

for(int i=0;i<v1.size();i++)
{
System.out.println("v1 "+v1.get(i));
}
The above statement prints "v1 0123456789" each time (as Vector references the same object )unless I uncomment the line in the above code which creates new StringBuffer.Can I reset this stringBuffer somehow instead of creating new StringBuffer and achieve the desired result.
Thanks,
Buggi
 
author
Posts: 14112
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No - if you want to have different objects in the list, you need to create different objects, obviously.
BTW, in the given snippet, using StringBuffer doesn't buy you anything - just use a String instead.
 
Ranch Hand
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Why not forget the StringBuffer and use

It'll do what you are looking for (why you are looking to do this is your own perogitive).
 
Wanderer
Posts: 18671
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Or maybe the objective was to get a set of Strings:
1
12
123
1234
etc.
In this case, just replace
v1.add(sb);
with
v1.add(sb.toString());
 
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