SCJP 1.6版考題 095

1. interface TestA{String toString();}
2. public class Test{
3.   public static void main(String[] args){
4.     System.out.println(new TestA(){
5.        public String toString(){return "test";}
6.     });
7.   }
8. }


What is the result?
  A. test
  B. null
  C. An exception is thrown at runtime.
  D. Compilation fails because of an error in line 1.
  E. Compilation fails because of an error in line 4.
  F. Compilation fails because of an error in line 5.

解答

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Ans: A

解說:

new TestA(){
    public String toString(){return "test";}
}
此種寫法是建立物件時，立即提供介面方法toString的實作。