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单项选择题 public class Test {
public static void main （String [] args） {
string foo = “blue”；
string bar = foo；
foo = “green”；
System.out.printIn（bar）；
}
}
What is the result？（）

A. An exception is thrown.
B. The code will not compile.
C. The program prints “null”
D. The program prints “blue”
E. The program prints “green”

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1.单项选择题 2. public class Foo implements Runnable （
3. public void run （Thread t） {
4. system.out.printIn（“Running.”）；
5. }
6. public static void main （String[] args） {
7. new thread （new Foo（））.start（）；
8. ）
9. ）
What is the result？（）

A. An exception is thrown.
B. The program exists without printing anything.
C. An error at line 1 causes compilation to fail.
D. An error at line 6 causes the compilation to fail.
E. “Running” is printed and the program exits.

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2.多项选择题Which two can directly cause a thread to stop executing？（）

A. Exiting from a synchronized block.
B. Calling the wait method on an object.
C. Calling the notify method on an object.
D. Calling the notifyAll method on an object.
E. Calling the setPriority method on a thread object.

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3.单项选择题 1. public class ForBar {
2. public static void main（String []args） {
3. int i = 0， j = 5；
4. tp： for （；；） {
5. i ++；
6. for（；；）
7. if（i > --j） break tp；
8. }
9. system.out.printIn（“i = ” + i + “， j = “+ j）；
10. }
11. }
What is the result？（）

A. The program runs and prints “i=1， j=0”
B. The program runs and prints “i=1， j=4”
C. The program runs and prints “i=3， j=4”
D. The program runs and prints “i=3， j=0”
E. An error at line 4 causes compilation to fail.
F. An error at line 7 causes compilation to fail.

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4.单项选择题 1. public class SwitchTest {
2. public static void main （String []args） {
3. System.out.PrintIn（“value =” +switchIt（4））；
4. }
5. public static int switchIt（int x） {
6. int j = 1；
7. switch （x） {
8. case 1： j++；
9. case 2： j++；
10. case 3： j++；
11. case 4： j++；
12. case 5： j++；
13. default：j++；
14. }
15. return j + x；
16. }
17. }
What is the output from line 3？（）

A. Value = 3
B. Value = 4
C. Value = 5
D. Value = 6
E. Value = 7
F. Value = 8

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5.单项选择题 public class ExceptionTest {
class TestException extends Exception {}
public void runTest （） throws TestException {}
public void test （） /* Point X*/ {
runTest （）；
}
}
At point X on line 4， which code can be added to make the code compile？（）

A. Throws Exception.
B. Catch （Exception e）.
C. Throws RuntimeException.
D. Catch （TestException e）.
E. No code is necessary.

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6.单项选择题 1.public class Test {
2.public static void main （String args[]） {
3.class Foo {
4.public int i = 3；
5.}
6.Object o = （Object） new Foo（）；
7.Foo foo = （Foo）o；
8.System.out.printIn（foo. i）；
9. }
10.}
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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7.多项选择题Which two declarations prevent the overriding of a method？（）

A. Final void methoda（） {}
B. Void final methoda（） {}
C. Static void methoda（） {}
D. Static final void methoda（） {}
E. Final abstract void methoda（） {}

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8.多项选择题 public class OuterClass {
private double d1 1.0；
//insert code here
}
You need to insert an inner class declaration at line2. Which two inner class declarations are valid？（）

A. static class InnerOne { public double methoda（） {return d1；} }
B. static class InnerOne { static double methoda（） {return d1；} }
C. private class InnerOne { public double methoda（） {return d1；} }
D. protected class InnerOne { static double methoda（） {return d1；} }
E. public abstract class InnerOne { public abstract double methoda（）； }

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9.多项选择题Which two statements are true regarding the creation of a default constructor？（）

A. The default constructor initializes method variables.
B. The default constructor invokes the no-parameter constructor of the superclass.
C. The default constructor initializes the instance variables declared in the class.
D. If a class lacks a no-parameter constructor，， but has other constructors， the compiler creates a default constructor.
E. The compiler creates a default constructor only when there are no other constructors for the class.

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10.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 modifier that will accomplish that will accomplish this objective？（）

A. Public
B. Private
C. Protected
D. Transient
E. No access modifier is required.

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