SCJP 1.6版考題 038
出自 陳富國維基館
1. class One{ 2. public One foo(){return this;} 3. } 4. class Two extends One{ 5. public One foo(){return this;} 6. } 7. class Three extends Two{ 8. //insert method here 9. } Which two methods, inserted individually, correctly complete the Three class? (Choose two.) A. public void foo(){} B. public int foo(){return 3;} C. public Two foo(){return this;} D. public One foo(){return this;} E. public Object foo(){return this;}
解答
Ans: C D
解說:
overriding 比較要注意的是C為何可以,是因為Two is One(繼承關係)
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