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String a = null;  a.concat(“abc”);  a.concat(“def”);  System.out.println(a);   What is the result?()  

  • A、 abc
  • B、 null
  • C、 abcdef
  • D、 Compilation fails.
  • E、 The code runs with no output.
  • F、 An exception is thrown at runtime.

参考答案

更多 “ String a = null;  a.concat(“abc”);  a.concat(“def”);  System.out.println(a);   What is the result?()  A、 abcB、 nullC、 abcdefD、 Compilation fails.E、 The code runs with no output.F、 An exception is thrown at runtime.” 相关考题
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