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Why we declare in the way List ab = new ArrayList(); what is the use of it?

Question Posted / rajacassian


Why we declare in the way List ab = new ArrayList(); what is the use of it?..

Answer / sravani gupta

When you declare List l = new ArrayList() l is limited to the methods provided by the interface List, while when you declare it ArrayList al = new ArrayList() it can use all methods and fields in an arraylist.

When you declare it List l then you afford yourself more flexibility as you can change out the ArrayList for something more appropriate at a later date if you want to without breaking any code

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