多选题Which three statements are true?（）AA final method in class X can be abstract if and only if X is abstract.BA protected method in class X can be overridden by any subclass of X.CA private static method can be called only within other static methods in c

第1题：

package foo；  public class Outer {  public static class Inner {  }  }   Which statement is true？（） 

• A、 Compilation fails.
• B、 An instance of the Inner class can be constructed with “new Outer.Inner（）”.
• C、 An instance of the Inner class cannot be constructed outside of package foo.
• D、 An instance of the Inner class can be constructed only from within the Outer class.
• E、 From within the package foo， and instance of the Inner class can be constructed with “new Inner（）”.

第2题：

Which two of statements are true？（）

• A、It is possible to synchronize static methods.
• B、When a thread has yielded as a result of yield（）， it releases its locks.
• C、When a thread is sleeping as a result of sleep（）， it releases its locks.
• D、The Object.wait（） method can be invoked only from a synchronized context.
• E、The Thread.sleep（） method can be invoked only from a synchronized context.
• F、When the thread scheduler receives a notify（） request， and notifies a thread， that thread immediately releases its lock.

第3题：

10. class Foo {  11. static void alpha（） { /* more code here */ }  12. void beta（） { /* more code here */ }  13. }  Which two are true？（）

• A、 Foo.beta（） is a valid invocation of beta（）.
• B、 Foo.alpha（） is a valid invocation of alpha（）.
• C、 Method beta（） can directly call method alpha（）.
• D、 Method alpha（） can directly call method beta（）.

第4题：

It is desirable that a certain method within a certain class can only be accessed by classes that are defined within the same package as the class of the method. How can such restrictions be enforced？（）  

• A、Mark the method with the keyword public.
• B、Mark the method with the keyword protected.
• C、Mark the method with the keyword private.
• D、Mark the method with the keyword package.
• E、Do not mark the method with any accessibility modifiers.

第5题：

package foo； public class Outer （  public static class Inner （  ）  ）   Which statement is true？ （） 

• A、 An instance of the Inner class can be constructed with “new Outer.Inner （）”
• B、 An instance of the inner class cannot be constructed outside of package foo.
• C、 An instance of the inner class can only be constructed from within the outer class.
• D、 From within the package bar， an instance of the inner class can be constructed with “new inner（）”

第6题：

public class SyncTest {  private int x；  private int y；  private synchronized void setX（ int i ） { x = i； }  private synchronized void setY（ int i ） { y = i； }  public void setXY（ int i ） { setX（i）； setY（i）； }  public synchronized boolean check（） { return x != y； }  }   Under which condition will check return true when called from a different class？ （） 

• A、 check can never return true.
• B、 check can return true when setXY is called by multiple threads.
• C、 check can return true when multiple threads call setX and setY separately.
• D、 check can return true only if SyncTest is changed to allow x and y to be set separately.

第7题：

public class SyncTest （  private int x；  private int y；  private synchronized void setX （int i） （x=1；）  private synchronized void setY （int i） （y=1；）  public void setXY（int 1）（set X（i）； setY（i）；）  public synchronized Boolean check（） （return x !=y；）  ）  Under which conditions will check （） return true when called from a different class？   

• A、 Check（） can never return true.
• B、 Check（） can return true when setXY is called by multiple threads.
• C、 Check（） can return true when multiple threads call setX and setY separately.
• D、 Check（） can only return true if SyncTest is changed to allow x and y to be setseparately.

第8题：

Which two statements are true？（）

• A、 An inner class may be declared as static.
• B、 An anonymous inner class can be declared as public.
• C、 An anonymous inner class can be declared as private.
• D、 An anonymous inner class can extend an abstract class.
• E、 An anonymous inner class can be declared as protected.

第9题：

Which the following two statements are true？（）

• A、 An inner class may be declared as static.
• B、 An anonymous inner class can be declared as public.
• C、 An anonymous inner class can be declared as private.
• D、 An anonymous inner class can extend an abstract class.
• E、 An anonymous inner class can be declared as protected.

第10题：

Which statement is true？（）

• A、 An anonymous inner class may be declared as final.
• B、 An anonymous inner class can be declared as private.
• C、 An anonymous inner class can implement multiple interfaces.
• D、 An anonymous inner class can access final variables in any enclosing scope.
• E、 Construction of an instance of a static inner class requires an instance of the enclosing outer class.