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单项选择题You want a class to have access to members of another class in the same package. Which is the most restrictive access that accomplishes this objective？（）

A. public
B. private
C. protected
D. transient
E. default access

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1.单项选择题 int i = 1，j = 10；
do {
if（i>j） {
break；
}
j--；
} while （++i <5）；
System.out.println（“i =” +i+” and j = “+j）；
What is the result？（）

A. i = 6 and j = 5
B. i = 5 and j = 5
C. i = 6 and j = 4
D. i = 5 and j = 6
E. i = 6 and j = 6

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2.多项选择题 class A {
A（） { }
}
class B extends A {
}
Which two statements are true？（）

A. Class B’s constructor is public.
B. Class B’s constructor has no arguments.
C. Class B’s constructor includes a call to this（）.
D. Class B’s constructor includes a call to super（）.

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3.单项选择题 interface Animal {
void soundOff（）；
}
class Elephant implements Animal {
public void soundOff（） {
System.out.println（“Trumpet”）；
}
}
class Lion implements Animal {
public void soundOff（） {
System.out.println（“Roar”）；
}
}
class Alpha1 {
static Animal get（ String choice ） {
if （ choice.equalsIgnoreCase（ “meat eater” ）） {
return new Lion（）；
} else {
return new Elephant（）；
}
}
}
Which compiles？（）

A. new Animal（）.soundOff（）；
B. Elephant e = new Alpha1（）；
C. Lion 1 = Alpha.get（“meat eater”）；
D. new Alpha1（）.get（“veggie”）.soundOff（）；

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4.单项选择题 1. class Test {
2. private Demo d；
3. void start（） {
4. d = new Demo（）；
5. this.takeDemo（d）；
6. }
7.
8. void takeDemo（Demo demo） {
9. demo = null；
10. demo = new Demo（）；
11. }
12. }
When is the Demo object， created on line 3， eligible for garbage collection？（）

A. After line 5.
B. After line 9.
C. After the start（） method completes.
D. When the takeDemo（） method completes.
E. When the instance running this code is made eligible for garbage collection.

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5.多项选择题Which two cause a compiler error？（）

A. float[] = new float（3）；
B. float f2[] = new float[]；
C. float[] f1 = new float[3]；
D. float f3[] = new float[3]；
E. float f5[] = { 1.0f， 2.0f， 2.0f }；
F. float f4[] = new float[] { 1.0f. 2.0f. 3.0f}；

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6.单项选择题 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.

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7.单项选择题Which interface does java.util.Hashable implement？（）

A. Java.util.Map.
B. Java.util.List.
C. Java.util.Hashable.
D. Java.util.Collection.

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8.多项选择题Which two interfaces provide the capability to store objects using a key-value pair？（）

A. Java.util.Map.
B. Java.util.Set.
C. Java.util.List.
D. Java.util.StoredSet.
E. Java.util.StoredMap.
F. Java.util.Collection.

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9.单项选择题 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）.

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10.多项选择题Which statements about static inner classes are true？（）

A. A static inner class requires a static initializer.
B. A static inner class requires an instance of the enclosing class.
C. A static inner class has no reference to an instance of the enclosing class.
D. A static inner class has access to the non-static members of the outer class.
E. Static members of a static inner class can be referenced using the class name of the static inner class.

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