单选题1. public class GC {  2. private Object o;  3. private void doSomethingElse(Object obj) { o = obj; }  4. public void doSomething() {  5. Object o = new Object();  6. doSomethingElse(o);  7. o = new Object();  8. doSomethingElse(null);  9.o=null;  10. }

题目
单选题
1. public class GC {  2. private Object o;  3. private void doSomethingElse(Object obj) { o = obj; }  4. public void doSomething() {  5. Object o = new Object();  6. doSomethingElse(o);  7. o = new Object();  8. doSomethingElse(null);  9.o=null;  10. }  11. }  When the doSomething method is called, after which line does the Object created in line 5 become available for garbage collection?()
A

 Line 5

B

 Line 6

C

 Line 7

D

 Line 8

E

 Line 9

F

 Line 10


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更多“单选题1. public class GC {  2. private Object o;  3. private void doSomethingElse(Object obj) { o = obj; }  4. public void doSomething() {  5. Object o = new Object();  6. doSomethingElse(o);  7. o = new Object();  8. doSomethingElse(null);  9.o=null;  10. }”相关问题
  • 第1题:

    1. public class GC {  2. private Object o;  3. private void doSomethingElse(Object obj) { o = obj; }  4. public void doSomething() {  5. Object o = new Object();  6. doSomethingElse(o);  7. o = new Object();  8. doSomethingElse(null);  9.o=null;  10. }  11. }  When the doSomething method is called, after which line does the Object created in line 5 become available for garbage collection?() 

    • A、 Line 5
    • B、 Line 6
    • C、 Line 7
    • D、 Line 8
    • E、 Line 9
    • F、 Line 10

    正确答案:D

  • 第2题:

    1.public class GC{ 2.private Objec to; 3.private void doSomethingElse(Object obj){o=obj;} 4.public void doSomething(){ 5.Object o=new Object(); 6.doSomethingElse(o); 7.o=new Object(); 8.doSomethingElse(null); 9.o=null; 10.} 11.} When the doSomething method is called,after which line does the Object created in line 5 become available for garbage collection?()

    • A、Line5
    • B、Line6
    • C、Line7
    • D、Line8
    • E、Line9
    • F、Line10

    正确答案:D

  • 第3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. return oa[0];  8. }  9. }   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 (that is, as the method returns)
    • D、 Never in this method.

    正确答案:D

  • 第4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).

    正确答案:C

  • 第5题:

    public class X {   public object m () {   object o = new float (3.14F);   object oa = new object [1];   oa[0]= o;   o = null;   oa[0] = null;   return o;   }   }   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).

    正确答案:C

  • 第6题:

    单选题
    1. public class Outer{  2. public void someOuterMethod() {  3. // Line 3  4. }  5. public class Inner{}  6. public static void main( String[]argv ) {  7. Outer o = new Outer();  8. // Line 8  9. }  10. }  Which instantiates an instance of Inner?()
    A

     new Inner(); // At line 3

    B

     new Inner(); // At line 8

    C

     new o.Inner(); // At line 8

    D

     new Outer.Inner(); // At line 8


    正确答案: A
    解析: 暂无解析

  • 第7题:

    单选题
    现有:  1.  import java.util.*;      2. class ForInTest  {  3.static List list - new ArrayList():      4.  5.static List getList()    {  return list;    }      6.  7.public static void main (Strincj[]  args)    {      8.list.add("a");  list.add("b");  list.add("c");      9.    //insert code here      10.    System.out.print (o);      11.    }      12.  }  第9行插入哪一项将输出abc?()
    A

     for(char o: list)

    B

     for (Object o:  o.getList())

    C

     for(Object o: getList();)

    D

     for(Object o: getList())

    E

     for(Object o: o.getList();)


    正确答案: D
    解析: 暂无解析

  • 第8题:

    多选题
    Which three will compile and run without exception?()
    A

    private synchronized Object o;

    B

    void go() {synchronized() { /* code here */ }

    C

    public synchronized void go() { /* code here */ }

    D

    private synchronized(this) void go() { /* code here */ }

    E

    void go() {synchronized(Object.class) { /* code here */ }

    F

    void go() {Object o = new Object();synchronized(o) { /* code here */ }


    正确答案: B,D
    解析: 暂无解析

  • 第9题:

    单选题
    现有:   3.  import java.util.*;   4.  class ForInTest {   5.    static List list = new ArrayList();   6.   7.    public static void main(String [] args) {   8.      list.add("a"); list.add("b"); list.add("c");   9.      //insert code here      10.     System.out.print(o);    11.   }   12. }   哪一行插入到第9行将导致输出“abc”?()
    A

     for(Object o : list)

    B

     for(Iterator o : list)

    C

     for(Object o : list.iterator())

    D

     for(Iterator o : list.iterator(); o.hasNext (); )


    正确答案: B
    解析: 暂无解析

  • 第10题:

    单选题
    1. import java.util.*;  2. class ForInTest {  3. static List list = new ArrayList();  4.  5. static List getList() { return list; }  6.  7. public static void main(String [] args) {  8. list.add("a"); list.add("b"); list.add("c");  9. // insert code here  10. System.out.print(o);  11. }  12. } 第 9 行插入哪一项将输出 abc?()
    A

    for(char o: list)

    B

    for(Object o: getList())

    C

    for(Object o: getList();)

    D

    for(Object o: o.getList())


    正确答案: D
    解析: 暂无解析

  • 第11题:

    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).


    正确答案: D
    解析: 暂无解析

  • 第12题:

    单选题
    3. import java.util.*;   4. class ForInTest {   5. static List list = new ArrayList();   6.   7. public static void main(String [] args) {   8. list.add("a"); list.add("b"); list.add("c");   9. //insert code here   10. System.out.print(o);   11. }   12. }   哪一行插入到第9行将导致输出“abc”?()
    A

     for(Object o : list)

    B

     for(Iterator o : list)

    C

     for(Object o : list.iterator())

    D

     for(Iterator o : list.iterator(); o.hasNext (); )


    正确答案: A
    解析: 暂无解析

  • 第13题:

    1. import java.util.*;  2. class ForInTest {  3. static List list = new ArrayList();  4.  5. static List getList() { return list; }  6.  7. public static void main(String [] args) {  8. list.add("a"); list.add("b"); list.add("c");  9. // insert code here  10. System.out.print(o);  11. }  12. } 第 9 行插入哪一项将输出 abc?() 

    • A、for(char o: list)
    • B、for(Object o: getList())
    • C、for(Object o: getList();)
    • D、for(Object o: o.getList())

    正确答案:B

  • 第14题:

    现有:  1.  import java.util.*;      2. class ForInTest  {  3.static List list - new ArrayList():      4.  5.static List getList()    {  return list;    }      6.  7.public static void main (Strincj[]  args)    {      8.list.add("a");  list.add("b");  list.add("c");      9.    //insert code here      10.    System.out.print (o);      11.    }      12.  }  第9行插入哪一项将输出abc?()     

    • A、 for(char o: list)
    • B、 for (Object o:  o.getList())
    • C、 for(Object o: getList();)
    • D、 for(Object o: getList())
    • E、 for(Object o: o.getList();)

    正确答案:D

  • 第15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.println(“i = “ + foo.i); }  }  What is the result?()  

    • A、 i = 3
    • B、 Compilation fails.
    • C、 A ClassCastException is thrown at line 6.
    • D、 A ClassCastException is thrown at line 7.

    正确答案:A

  • 第16题:

    Which three will compile and run without exception?()

    • A、private synchronized Object o;
    • B、void go(){   synchronized(){/* code here */}
    • C、public synchronized void go(){/* code here */}
    • D、private synchronized(this) void go(){/* code here */}
    • E、void go(){   synchronized(Object.class){/* code here */}
    • F、void go(){   Object o = new Object();   synchronized(o){/* code here */}

    正确答案:C,E,F

  • 第17题:

    3. import java.util.*;   4. class ForInTest {   5. static List list = new ArrayList();   6.   7. public static void main(String [] args) {   8. list.add("a"); list.add("b"); list.add("c");   9. //insert code here   10. System.out.print(o);   11. }   12. }   哪一行插入到第9行将导致输出“abc”?()  

    • A、 for(Object o : list)
    • B、 for(Iterator o : list)
    • C、 for(Object o : list.iterator())
    • D、 for(Iterator o : list.iterator(); o.hasNext (); )

    正确答案:A

  • 第18题:

    单选题
    10. public Object m() { 11. Object o = new Float(3.14F); 12. Object [] oa = new Object[1]; 13. oa[0] = o; 14. o = null; 15. return oa[0]; 16. } When is the Float object, created in line 11, eligible for garbage collection?()
    A

     Just after line 13.

    B

     Just after line 14.

    C

     Never in this method.

    D

     Just after line 15 (that is, as the method returns).


    正确答案: A
    解析: The correct answer to this question is C. The object is never garbage collected simply because the method returns it. Think about it, the message that receives the object might depend on it so it must be sure that the object received by the method wont be garbage collected. Only in this situation a local object  wont be eligible for garbage collection. Otherwise, a local object is eligible for garbage collection as soon as the method ends.

  • 第19题:

    单选题
    1.public class GC{ 2.private Objec to; 3.private void doSomethingElse(Object obj){o=obj;} 4.public void doSomething(){ 5.Object o=new Object(); 6.doSomethingElse(o); 7.o=new Object(); 8.doSomethingElse(null); 9.o=null; 10.} 11.} When the doSomething method is called,after which line does the Object created in line 5 become available for garbage collection?()
    A

    Line5

    B

    Line6

    C

    Line7

    D

    Line8

    E

    Line9

    F

    Line10


    正确答案: A
    解析: 暂无解析

  • 第20题:

    单选题
    1. public class GC {  2. private Object o;  3. private void doSomethingElse(Object obj) { o = obj; }  4. public void doSomething() {  5. Object o = new Object();  6. doSomethingElse(o);  7. o = new Object();  8. doSomethingElse(null);  9.o=null;  10. }  11. }  When the doSomething method is called, after which line does the Object created in line 5 become available for garbage collection?()
    A

     Line 5

    B

     Line 6

    C

     Line 7

    D

     Line 8

    E

     Line 9

    F

     Line 10


    正确答案: A
    解析: 暂无解析

  • 第21题:

    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.println(“i = “ + foo.i); }  }  What is the result?()
    A

     i = 3

    B

     Compilation fails.

    C

     A ClassCastException is thrown at line 6.

    D

     A ClassCastException is thrown at line 7.


    正确答案: D
    解析: 暂无解析

  • 第22题:

    单选题
    public class X {   public object m () {   object o = new float (3.14F);   object oa = new object [1];   oa[0]= o;   o = null;   oa[0] = null;   return o;   }   }   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).


    正确答案: C
    解析: 暂无解析

  • 第23题:

    单选题
    public class X {  public object m () {   object o = new float (3.14F);   object oa = new object [1];   oa[0]= o;   o = null;   return oa[0];   }   }   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 (that is, as the method returns)

    D

     Never in this method.


    正确答案: C
    解析: 暂无解析

  • 第24题:

    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. return oa[0];  8. }  9. }   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 (that is, as the method returns)

    D

     Never in this method.


    正确答案: A
    解析: 暂无解析