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class A {   public String toString () {   return “4”;   }   }   class B extends A {   8. public String toString () {   return super.toString() + “3”;   }   }   public class Test {   public static void main(Stringargs) {   System.out.printIn(new B());   }   }   What is the result?()  

  • A、 Compilation succeeds and 4 is printed.
  • B、 Compilation succeeds and 43 is printed.
  • C、 An error on line 9 causes compilation to fail.
  • D、 An error on line 14 causes compilation to fail.
  • E、 Compilation succeeds but an exception is thrown at line 9.

参考答案

更多 “ class A {   public String toString () {   return “4”;   }   }   class B extends A {   8. public String toString () {   return super.toString() + “3”;   }   }   public class Test {   public static void main(Stringargs) {   System.out.printIn(new B());   }   }   What is the result?()  A、 Compilation succeeds and 4 is printed.B、 Compilation succeeds and 43 is printed.C、 An error on line 9 causes compilation to fail.D、 An error on line 14 causes compilation to fail.E、 Compilation succeeds but an exception is thrown at line 9.” 相关考题
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考题 单选题Given the following code:     1) class Parent {     2) private String name;     3) public Parent(){}     4) }  5) public class Child extends Parent {     6) private String department;  7) public Child() {}  8) public String getValue(){ return name; }     9) public static void main(String arg[]) {     10) Parent p = new Parent();     11) }  12) }  Which line will cause error?()A  line 3B  line 6C  line 7D  line 8E  line 10

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考题 多选题public class X {  public X aMethod() { return this;}  }  public class Y extends X {  }  Which two methods can be added to the definition of class Y?()Apublic void aMethod() {}Bprivate void aMethod() {}Cpublic void aMethod(String s) {}Dprivate Y aMethod() { return null; }Epublic X aMethod() { return new Y(); }

考题 单选题class Super {  public Integer getLenght() { return new Integer(4); } }  public class Sub extends Super {  public Long GetLenght() { return new Long(5); }  public static void main(String[] args) { Super sooper = new Super();  Sub sub = new Sub();  System.out.println(  sooper.getLenght().toString() + “,” +  sub.getLenght().toString() ); } }  What is the output?()A  4,4B  4,5C  5,4D  5,5E  Compilation fails.

考题 单选题class Super { public int getLenght() { return 4; } } public class Sub extends Super { public long getLenght() { return 5; } public static void main(String[] args) {Super sooper = new Super(); Sub sub = new Sub(); System.out.println( sooper.getLenght() + “,” + sub.getLenght() ); } } What is the output? ()A  4,4B  4,5C  5,4D  5,5E  Compilation fails.

考题 填空题Public class test (  Public static void main (String args[])  (  System.out.printIn (6 ^ 3);  )  )   What is the output?()

考题 单选题class A {   public String toString () {   return “4”;   }   }   class B extends A {   8. public String toString () {   return super.toString() + “3”;   }   }   public class Test {   public static void main(Stringargs) {   System.out.printIn(new B());   }   }   What is the result?()A  Compilation succeeds and 4 is printed.B  Compilation succeeds and 43 is printed.C  An error on line 9 causes compilation to fail.D  An error on line 14 causes compilation to fail.E  Compilation succeeds but an exception is thrown at line 9.