单选题1. public class X {  2. public object m ()  {  3. object o = new float (3.14F);  4. object [] oa = new object [1]; 5. oa[0]= o;  6. o = null;  7. oa[0] = null;  10. return o;  9. }  10. }  When is the float object created in line 3, eligible for garbage collection?()A Just after line 5.B Just after line 6.C Just after line 7.D Just after line 8(that is, as the method returns).

单选题
1. public class X {  2. public object m ()  {  3. object o = new float (3.14F);  4. object [] oa = new object [1]; 5. oa[0]= o;  6. o = null;  7. oa[0] = null;  10. return o;  9. }  10. }  When is the float object created in line 3, eligible for garbage collection?()
A

 Just after line 5.

B

 Just after line 6.

C

 Just after line 7.

D

 Just after line 8(that is, as the method returns).


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单选题1. public class X {  2. public object m ()  {  3. object o = new float (3.14F);  4. object [] oa = new object [1]; 5. oa[0]= o;  6. o = null;  7. oa[0] = null;  10. return o;  9. }  10. }  When is the float object created in line 3, eligible for garbage collection?()A Just after line 5.B Just after line 6.C Just after line 7.D Just after line 8(that is, as the method returns).

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单选题public class Test {   public static void main (String args) {   class Foo {   public int i = 3;  }   Object o = (Object) new Foo();   Foo foo = (Foo)o;   System.out.printIn(foo. i);  }   }   What is the result?()A Compilation will fail.B Compilation will succeed and the program will print “3”C Compilation will succeed but the program will throw a ClassCastException at line 6.D Compilation will succeed but the program will throw a ClassCastException at line 7.

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多选题Given:  1.  public class ConstOver {  2.  public constOver(int x, int y, int z) {  3.  }  4.  }   Which two overload the ConstOver Constructor?()AConstOver() {}Bprotected int ConstOver(){}Cprivate ConstOver(int z, int y, byte x ) {}Dpublic Object ConstOver(Int x, int y, int z) {}Epubic void ConstOver (byte x, byte y, byte z) {}

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单选题public class Score implements Comparable {  private int wins, losses;  public Score(int w, int 1) { wins = w; losses = 1; }  public int getWins() { return wins; }  public int getLosses() { return losses; }  public String toString() {  return “”; }  // insert code here  }  Which method will complete this class?()A public int compareTo(Object o) {/*mode code here*/}B public int compareTo(Score other) {/*more code here*/}C public int compare(Score s1,Score s2){/*more code here*/}D public int compare(Object o1,Object o2){/*more code here*/}