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List interface and toString( ) method

 
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The List interface does not specify a toString( ) method, and neither does the Collection interface (the only other interface that List implements). Yet I am able to call this method on an object declared as a List. For example:
List myList;
... (assigns some object to myList)
String s = myList.toString();
Of course I know that Object implements toString, and all objects extend Object, so any object must have a toString method, but since the Interface List doesn't extend Object, I thought my class wouldn't compile. It looks like the compiler assumes that all objects have the methods of the Object class?
Tony
 
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Yes, if you don't explicitly extend an existing class, your class will then just extend Object, thus getting all the methods from the Object class, including toString(). It also seems that interfaces automatically inherit the methods from Object as well...
 
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Since you can never instantiate an interface, once you get to the point you have a referecne to an implementing instance, it must be an object, not an interface, and thus will always have the Object methods handy.
hth,
bear
 
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