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Greenhorn
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// Line 1:
list < ? super String> list = new ArrayList <String>> ();


// Line 2:
list.add(new Object());

Drag and Drop the following options over Line 1 and Line 2. Drag the relevant fragment over the line to indicate whether or not the Line will not compile, or if will compile, whether it will throw Exceptions.

The answers are :
Line1: compiles fine with no runtime exceptions.
Line2:compiletime error.

please explain.
 
Ranch Hand
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Hi !!!

A List<? super String> may contain lists of type String and any higher type.
But you can add directly only Strings, nothing higher.
 
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