Java开发网 - [经典]JAVA---SCJP考题分析

Java开发网

您没有登录

» Java开发网 » Java SE 综合讨论区

打印话题 寄给朋友 订阅主题

作者

[经典]JAVA---SCJP考题分析

smartzhao

超级元老

CJSDN高级会员

发贴: 309
积分: 180

于 2002-08-03 03:10

由于先的JDK1.4版中去掉了I/O和AWT所以我在分析这两部分的时候没有太仔细! 其实在你考试的时候看到题目你就应该能看书考点,通过绝对没问题,反之通过也是........呵呵 JAVA语言就那么几个优点,SUN会翻来覆去的考的!

1. Given:

1. public class test (
2. public static void main (String args[]) {
3. int i = 0xFFFFFFF1;
4. int j = ~i;
5.
6. }
7. )

What is the decimal value of j at line 5?

A. 0
B. 1
C. 14
D. -15
E. An error at line 3 causes compilation to fail.
F. An error at line 4 causes compilation to fail.
//考点:按位取反的操作符使用

2. Given:

Integer i = new Integer (42);
Long 1 = new Long (42);
Double d = new Double (42.0);

Which two expressions evaluate to True? (Choose Two)

A. (i ==1)
B. (i == d)
C. (d == 1)
D. (i.equals Food

)
E. (d.equals Light Bulb

)
F. (i.equals (42))
//考点:==和equals方法的区别

3. Click the exhibit button:

1. public class test (
2. private static int j = 0;
3.
4. private static boolean methodB(int k) (
5. j += k;
6. return true;
7. )
8.
9. public static void methodA(int i) {
10. boolean b:
11. b = i < 10 | methodB (4);
12. b = i < 10 || methodB Musical Note

;
13. )
14.
15. public static void main (String args[] } (
16. methodA (0);
17. system.out.printIn(j);
18. )
19. )

What is the result?

A. The program prints “0”
B. The program prints “4”
C. The program prints “8”
D. The program prints “12”
E. The code does not complete
//考点:或运算和短逻辑或运算

4. Given:

1.Public class test (
2. Public static void main (String args[]) (
3. System.out.printIn (6 ^ 3);
4. )
5.)

What is the output?

Ans:
//考点:异或的符号实际使用

5. Given:

1. public class Foo {
2. public static void main (String [] args) {
3. StringBuffer a = new StringBuffer (“A”);
4. StringBuffer b = new StringBuffer (“B”);
5. operate (a,b);
6. system.out.printIn{a + “,” +b};
7. )
8. static void operate (StringBuffer x, StringBuffer y) {
9. x.append {y};
10. y = x;
11. )
12. }

What is the result?

A. The code compiles and prints “A,B”.
B. The code compiles and prints “A,A”.
C. The code compiles and prints “B,B”.
D. The code compiles and prints “AB,B”.
E. The code compiles and prints “AB,AB”.
F. The code does not compile because “+” cannot be overloaded for StringBuffer.
//考点:StringBuffer类的使用方法

6. Click the exhibit button:

1. Public class test (
2. Public static void stringReplace (String text) (
3. Text = text.replace (‘j’ , ‘i’);
4. )
5.
6. public static void bufferReplace (StringBuffer text) (
7. text = text.append (“C”)
8. )
9.
10. public static void main (String args[]} (
11. String textString = new String (“java”);
12. StringBuffer text BufferString = new StringBuffer (“java”);
13.
14. stringReplace (textString);
15. BufferReplace (textBuffer);
16.
17. System.out.printIn (textString + textBuffer);
18. }
19. )

What is the output?
Ans:
//考点:String 和StringBuffer类的方法和使用

7. Click the Exhibit button:

1. public class test {
2. public static void add3 (Integer i) }
3. int val = i.intValue ( );
4. val += 3;
5. i = new Integer (val);
6. }
7.
8. public static void main (String args [ ] ) {
9. Integer i = new Integer (0);
10. add3 Light Bulb

;
11. system.out.printIn (i.intValue ( ) );
12. }
13. )

What is the result?

A. Compilation will fail.
B. The program prints “0”.
C. The program prints “3”.
D. Compilation will succeed but an exception will be thrown at line 3.
//考点:原始数据类型是传值的.

8. Given:

1. public class ConstOver {
2. public ConstOver (int x, int y, int z) {
3. }
4. }

Which two overload the ConstOver constructor? (Choose Two)

A. ConstOver ( ) { }
B. Protected int ConstOver ( ) { }
C. Private ConstOver (int z, int y, byte x) { }
D. public Object ConstOver (int x, int y, int z) { }
E. public void ConstOver (byte x, byte y, byte z) { }
//考点:构造器的重载问题

9. Given:

1. public class MethodOver {
2. public void setVar (int a, int b, float c) {
3. }
4. }

Which two overload the setVar method? (Choose Two)

A. private void setVar (int a, float c, int b) { }
B. protected void setVar (int a, int b, float c) { }
C. public int setVar (int a, float c, int b) (return a Wink

D. public int setVar (int a, int b, float c) (return a Wink

E. protected float setVar (int a, int b, float c) (return c Wink

//考点:方法的重载

10. Given:

1. class BaseClass {
2. Private float x = 1.0f ;
3. protected float getVar ( ) ( return x Wink

4. }
5. class Subclass extends BaseClass (
6. private float x = 2.0f;
7. //insert code here
8. )

Which two are valid examples of method overriding? (Choose Two)

A. float getVar ( ) { return x;}
B. public float getVar ( ) { return x;}
C. float double getVar ( ) { return x;}
D. protected float getVar ( ) { return x;}
E. public float getVar (float f ) { return f;}
//考点:方法的覆盖

11. Which two demonstrate an “is a” relationship? (Choose Two)

A. public interface Person { }
public class Employee extends Person { }
B. public interface Shape { }
public class Employee extends Shape { }
C. public interface Color { }
public class Employee extends Color { }
D. public class Species { }
public class Animal (private Species species Wink

E. interface Component { }
Class Container implements Component (
Private Component[ ] children;
)
//考点 Blush

S A的关系问题

12. 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.
//考点:匿名内部类的声明和存取问题

13. Given:

1. package foo;
2.
3. public class Outer (
4. public static class Inner (
5. )
6. )

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()”
//考点:内部类的实例化问题

14. Click the exhibit button:

1. public class enclosingone ( 2. public class insideone{} 3. ) 4. public class inertest( 5. public static void main (string[]args)( 6. enclosingone eo= new enclosingone (); 7. //insert code here 8. ) 9. )

Which statement at line 7 constructs an instance of the inner class?

A. InsideOnew ei= eo.new InsideOn();
B. Eo.InsideOne ei = eo.new InsideOne();
C. InsideOne ei = EnclosingOne.new InsideOne();
D. EnclosingOne.InsideOne ei = eo.new InsideOne();
//考点:内部类的实例化问题

15. Click the exhibit button:

1. interface foo { 2. int k = 0; 3. ] 4. 5. public class test implements Foo ( 6. public static void main(String args[]) ( 7. int i; 8. Test test = new test (); 9. i= test.k; 10. i= Test.k; 11. i= Foo.k; 12. ) 13. ) 14.

What is the result?

A. Compilation succeeds.
B. An error at line 2 causes compilation to fail.
C. An error at line 9 causes compilation to fail.
D. An error at line 10 causes compilation to fail.
E. An error at line 11 causes compilation to fail.
//考点:接口中的变量实际上是常量

16. Given:

1. //point X
2. public class foo (
3. public static void main (String[]args) throws Exception {
4. printWriter out = new PrintWriter (new
5. java.io.outputStreamWriter (System.out), true;
6. out.printIn(“Hello”);
7. }
8. )

Which statement at PointX on line 1 allows this code to compile and run?

A. import java.io.PrintWriter;
B. include java.io.PrintWriter;
C. import java.io.OutputStreamWriter;
D. include java.io.OutputStreamWriter;
E. no statement is needed.
//考点:JAVA源文件声明先后问题

17. Which two statements are reserved words in Java? (Choose Two)

A. run
B. import
C. default
D. implement
//考点:关键字的问题

18. Which three are valid declarations of a float? (Choose Three)

A. float foo = -1;
B. float foo = 1.0;
C. float foo = 42e1;
D. float foo = 2.02f;
E. float foo = 3.03d;
F. float foo = 0x0123;
//考点:原始数据类型的声明问题及原始数据类型自动问题

19. Given:

8. int index = 1;
9. boolean[] test = new Boolean[3];
10. boolean foo= test [index];

What is the result?

A. foo has the value of 0
B. foo has the value of null
C. foo has the value of true
D. foo has the value of false
E. an exception is thrown
F. the code will not compile
//考点:BOOLEAN默认值的问题

20. Given:

1. public class test(
2. public static void main(string[]args){
3. string foo = args [1];
4. string foo = args [2];
5. string foo = args [3];
6. }
7. }

And the command line invocation:
Java Test red green blue

What is the result?

A. baz has the value of “”
B. baz has the value of null
C. baz has the value of “red”
D. baz has the value of “blue”
E. bax has the value of “green”
F. the code does not compile
G. the program throws an exception
//考点:数组下标值问题
21. Given:

8. int index = 1;
9. int [] foo = new int [3];
10. int bar = foo [index];
11. int baz = bar + index;

What is the result?

A. baz has the value of 0
B. baz has the value of 1
C. baz has the value of 2
D. an exception is thrown
E. the code will not compile
//考点:数组使用问题
22. Given:

1. public class foo {
2. public static void main (String[]args) {
3. String s;
4. system.out.printIn (“s=” + s);
5. }
6. }

What is the result?

A. The code compiles and “s=” is printed.
B. The code compiles and “s=null” is printed.
C. The code does not compile because string s is not initialized.
D. The code does not compile because string s cannot be referenced.
E. The code compiles, but a NullPointerException is thrown when toString is called.
//考点:引用型默认值问题问题
23. Which will declare a method that forces a subclass to implement it?

A. Public double methoda();
B. Static void methoda (double d1) {}
C. Public native double methoda();
D. Abstract public void methoda();
E. Protected void methoda (double d1){}
//考点:关键字使用问题
24. You want subclasses in any package to have access to members of a superclass. Which is the most restrictive access modifier that will accomplish this objective?

A. Public
B. Private
C. Protected
D. Transient
E. No access modifier is qualified
//考点:关键字问题
25. Given:

1. abstract class abstrctIt {
2. abstract float getFloat ();
3. )
4. public class AbstractTest extends AbstractIt {
5. private float f1= 1.0f;
6. private float getFloat () {return f1;}
7. }

What is the result?

A. Compilation is successful.
B. An error on line 6 causes a runtime failure.
C. An error at line 6 causes compilation to fail.
D. An error at line 2 causes compilation to fail.
//考点:方法覆盖问题
26. Click the exhibit button:

1. public class test( 2. public int aMethod()[ 3. static int i=0; 4. i++; 5. return I; 6. ) 7. public static void main (String args[]){ 8. test test = new test(); 9. test.aMethod(); 10. int j = test.aMethod(); 11. System.out.printIn(j); 12. ] 13. }

What is the result?

A. Compilation will fail.
B. Compilation will succeed and the program will print “0”.
C. Compilation will succeed and the program will print “1”.
D. Compilation will succeed and the program will print “2”.
//考点:STATIC关键字问题
27. Given:

1. class super {
2. public float getNum() {return 3.0f;}
3. )
4.
5. public class Sub extends Super {
6.
7. )

Which method, placed at line 6, will cause a compiler error?

A. public float getNum() {return 4.0f; }
B. public void getNum () { }
C. public void getNum (double d) { }
D. public double getNum (float d) {retrun 4.0f; }
//考点:方法覆盖问题
28. Which declaration prevents creating a subclass of an outer class?

A. static class FooBar{}
B. private class FooBar{}
C. abstract public class FooBar{}
D. final public class FooBar{}
E. final abstract class FooBar{}
//考点:关键字使用问题
29. Given:

1. byte [] arry1, array2[];
2. byte array3 [][];
3. byte[][] array4;

If each array has been initialized, which statement will cause a compiler error?

A. array2 = array1;
B. array2 = array3;
C. array2 = array4;
D. both A and B
E. both A and C
F. both B and C
//考点:数组声明问题
30. Click the exhibit button:

1. class super ( 2. public int I = 0; 3. 4. public super (string text) ( 5. I = 1 6. ) 7. ) 8. 9. public class sub extends super ( 10. public sub (string text) ( 11. i= 2 12. ) 13. 14. public static void main (straing args[]) ( 15. sub sub = new sub (“Hello”); 16. system.out. PrintIn(sub.i); 17. ) 18. )

What is the result?
A. Compilation will fail.
B. Compilation will succeed and the program will print “0”.
C. Compilation will succeed and the program will print “1”.
D. Compilation will succeed and the program will print “2”.
//考点:方法覆盖问题
31. Given:

1. public class returnIt (
2. returnType methodA(byte x, double y) (
3. return (short) x/y * 2;
4. )
5. )

What is the valid returnType for methodA in line 2?

A. int
B. byte
C. long
D. short
E. float
F. double
//考点:操作符号执行顺序及原始数据类型自动转换问题
32. Given the ActionEvent, which method allows you to identify the affected component?

A. getClass
B. getTarget
C. getSource
D. getComponent
E. getTargetComponent
//考点:AWT问题
33. Which is a method of the MouseMotionListener interface?

A. Public void mouseMoved(MouseEvent)
B. Public boolean mouseMoved(MouseEvent)
C. Public void mouseMoved(MouseMotionEvent)
D. Public boolean MouseMoved(MouseMotionEvent)
E. Public boolean mouseMoved(MouseMotionEvent)
//考点:AWT问题
34. Click the exhibit button:

1. import java.awt*; 2. 3. public class X extends Frame ( 4. public static void main(string []args) ( 5. X x = new X (); 6. X.pack(); 7. x.setVisible(true); 8. ) 9. 10. public X () ( 11. setlayout (new GridLayout (2,2)); 12. 13. Panel p1 = new panel(); 14. Add(p1); 15. Button b1= new Button (“One”); 16. P1.add(b1); 17. 18. Panel p2 = new panel(); 19. Add(p2); 20. Button b2= new Button (“Two”); 21. P2.add(b2); 22. 23. Button b3= new Button (“Three”); 24. add(b3); 25. 26. Button b4= new Button (“Four”); 27. add(b4); 28. ) 29. )

Which two statements are true? (Choose Two)

A. All the buttons change height if the frame height is resized.
B. All the buttons change width if the Frame width is resized.
C. The size of the button labeled “One” is constant even if the Frame is resized.
D. Both width and height of the button labeled “Three” might change if the Frame is resized.
//考点:AWT问题
35. You are assigned the task of building a panel containing a TextArea at the top, a label directly below it, and a button directly below the label. If the three components are added directly to the panel, which layout manager can the panel use to ensure that the TextArea absorbs all of the free vertical space when the panel is resized?

A. GridLayout
B. CardLayout
C. FlowLayout
D. BorderLayout
E. GridBagLayout
//考点布局管理器问题
36. Which of the following gets the name of the parent directory file “file.txt”?

A. String name= File.getParentName(“file.txt”);
B. String name= (new File(“file.txt”)).getParent();
C. String name = (new File(“file.txt”)).getParentName();
D. String name= (new File(“file.txt”)).getParentFile();
E. Directory dir=(new File (“file.txt”)).getParentDir();
String name= dir.getName();
//考点 Blush

/O问题
37. Which can be used to encode charS for output?

A. java.io.OutputStream
B. java.io.OutputStreamWriter
C. java.io.EncodeOutputStream
D. java.io.EncodeWriter
E. java.io.BufferedOutputStream
//考点 Blush

/O问题
38. The file “file.txt” exists on the file system and contains ASCII text.

Given:

38. try {
39. File f = new File(“file.txt”);
40. OutputStream out = new FileOutputStream(f, true);
41. }
42. catch (IOException) {}

What is the result?

A. The code does not compile.
B. The code runs and no change is made to the file.
C. The code runs and sets the length of the file to 0.
D. An exception is thrown because the file is not closed.
E. The code runs and deletes the file from the file system.
//考点 Blush

/O问题
39. Which constructs a DataOutputStream?

A. new dataOutputStream(“out.txt”);
B. new dataOutputStream(new file(“out.txt”));
C. new dataOutputStream(new writer(“out.txt”));
D. new dataOutputStream(new FileWriter(“out.txt”));
E. new dataOutputStream(new OutputStream(“out.txt”));
F. new dataOutputStream(new FileOutputStream(“out.txt”));
//考点 Blush

/O问题
40. What writes the text “<end>” to the end of the file “file.txt”?

A. OutputStream out= new FileOutputStream (“file.txt”);
Out.writeBytes (“<end>/n”);
B. OutputStream os= new FileOutputStream (“file.txt”, true);
DataOutputStream out = new DataOutputStream(os);
out.writeBytes (“<end>/n”);
C. OutputStream os= new FileOutputStream (“file.txt”);
DataOutputStream out = new DataOutputStream(os);
out.writeBytes (“<end>/n”);
D. OutputStream os= new OutputStream (“file.txt”, true);
DataOutputStream out = new DataOutputStream(os);
out.writeBytes (“<end>/n”);
//考点 Blush

/O问题
41. Given:

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
//考点:垃圾收集问题
42. Given:

3. string foo = “ABCDE”;
4. foo.substring(3);
5. foo.concat(“XYZ”);
6.

Type the value of foo at line 6.

Ans:

//考点:STRING类方法使用问题
43. Which method is an appropriate way to determine the cosine of 42 degrees?

A. double d = Math.cos(42);
B. double d = Math.cosine(42);
C. double d = Math.cos(Math.toRadians(42));
D. double d = Math.cos(Math.toDegrees(42));
E. double d = Math.cosine(Math.toRadians(42));
//考点:数学类使用问题
44. You need to store elements in a collection that guarantees that no duplicates are stored and all elements can be accessed in natural order. Which interface provides that capability?

A. java.util.Map
B. java.util.Set
C. java.util.List
D. java.util.StoredSet
E. java.util.StoredMap
F. java.util.Collection
//考点:COLLECTION使用问题
45. Which statement is true for the class java.util.HashSet?

A. The elements in the collection are ordered.
B. The collection is guaranteed to be immutable.
C. The elements in the collection are guaranteed to be unique.
D. The elements in the collection are accessed using a unique key.
E. The elements in the collections are guaranteed to be synchronized.
//考点:COLLECTION使用问题
46. Given:

1. public class IfTest (
2. public static void main(string[]args) {
3. int x = 3;
4. int y = 1;
5. if (x = y)
6. system.out.printIn(“Not equal”);
7. else
8. system.out.printIn(“Equal”);
9. }
10. )

What is the result?
//考点:=不等于= =
A. The output is “Equal”.
B. The output in “Not Equal”.
C. An error at line 5 causes compilation to fall.
D. The program executes but does not print a message.

47. Click the exhibit button:

1. public class test ( 2. public static void main(string args[]) { 3. int 1= 0; 4. while Light Bulb

{ 5. if (i==4) { 6. break; 7. ) 8. ++i; 9. ) 10. 11. ) 12. )

What is the value of i at line 10?

A. 0
B. 3
C. 4
D. 5
E. the code will not compile
//考点:循环嵌套问题
48. Given:

3. int i= 1, j= 10 ;
4. do (
5. if (i++> --j) continue;
6. ) while (i<5);

After execution, what are the values for I and j?

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
//考点:循环嵌套问题
49. Given:

1. switch Light Bulb

{
2. default
3. System.out.printIn(“Hello”);
4. )

What are the two acceptable types for the variable i? (Choose Two)

A. char
B. byte
C. float
D. double
E. object
//考点:关键字问题
50. Given:

1. public class foo {
2. public static void main (string[]args)
3. try {return;}
4. finally {system.out.printIn(“Finally”);}
5. }
6. )

What is the result?

A. The program runs and prints nothing.
B. The program runs and prints “Finally”.
C. The code compiles, but an exception is thrown at runtime.
D. The code will not compile because the catch block is missing.
//考点:TRY CATCH 例外捕捉执行顺序问题
51. Click the exhibit button.

1. import java.io.IOException; 2. public class ExceptionTest( 3. public static void main (String[]args) 4. try ( 5. methodA(); 6. ) catch (IOException e) ( 7. system.out.printIn(“Caught IOException”); 8. ) catch (Exception e) ( 9. system.out.printIn(“Caught Exception”); 10. ) 11. ) 12. public void methodA () { 13. throw new IOException (); 14. ) 15. )

What is the result?
A. The code will not compile.
B. The output is caught exception.
C. The output is caught IOException.
D. The program executes normally without printing a message.
//考点:TRY CATCH 例外捕捉顺序问题
52. Click the exhibit button:

1. public class test { 2. public static string output = “” 3. 4. public static void foo(int i) { 5. try { 6. if(i= =1) { 7. throw new Exception (); 8. } 9. output += “1”; 10. ) 11. catch(Exception e) { 12. output += “2”; 13. return; 14. ) 15. finally ( 16. output += “3”; 17. ) 18. output += “4”; 19. ) 20. 21. public static void main (string args[]) ( 22. foo(0); 23. foo(1); 24. 25. ) 26. )

What is the value of the variable output at line 24?

Ans:

//考点:TRY CATCH 例外捕捉问题
53. Given:

1. public class Foo implements Runnable (
2. public void run (Thread t) {
3. system.out.printIn(“Running.”);
4. }
5. public static void main (String[] args) {
6. new thread (new Foo()).start();
7. )
8. )

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 2 causes the compilation to fail.
E. “Running” is printed and the program exits
//考点:线程启动方法
54. Which statement is true?

A. If only one thread is blocked in the wait method of an object, and another thread executes the modify on that same object, then the first thread immediately resumes execution.
B. If a thread is blocked in the wait method of an object, and another thread executes the notify method on the same object, it is still possible that the first thread might never resume execution.
C. If a thread is blocked in the wait method of an object, and another thread executes the notify method on the same object, then the first thread definitely resumes execution as a direct and sole consequence of the notify call.
D. If two threads are blocked in the wait method of one object, and another thread executes the notify method on the same object, then the first thread that executed the wait call first definitely resumes execution as a direct and sole consequence of the notify call.
//考点:线程方法问题
55. Which two CANNOT directly cause a thread to stop executing? (Choose Two)

A. Calling the yield method
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 start method on another Thread object
//考点:线程方法问题
56. Which two can be used to create a new Thread? (Choose Two)

A. Extend java.lang.Thread and override the run method.
B. Extend java.lang.Runnable and override the start method.
C. Implement java.lang.thread and implement the run method.
D. Implement java.lang.Runnable and implement the run method.
E. Implement java.lang.Thread and implement the start method.
//考点:创建线程方法问题
57. Given:

1. public class SyncTest (
2. private int x;
3. private int y;
4. private synchronized void setX (int i) (x=1 Wink

5. private synchronized void setY (int i) (y=1 Wink

6. public void setXY(int 1)(set X Light Bulb

; setY

7. public synchronized Boolean check() (return x !=y Wink

8. )

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 set separately.
//考点:线程方法问题
58. Click the exhibit button:

1. class A implements runable ( 2. int i; 3. public void run () ( 4. try ( 5. thread.sleep(5000); 6. i= 10; 7. ) catch(InterruptedException e) {} 8. ) 9. ) 10. 11. public class Test { 12. public static void main (string args[]) ( 13. try ( 14. A a = new A (); 15. Thread t = new Thread Angel

; 16. t.start(); 17. 18. int j= a.i; 19. 20. ) catch (Exception e) {} 21. ) 22. )

Which statement al line 17 will ensure that j=10 at line 19?

A. a.wait();
B. t.wait();
C. t.join();
D. t.yield();
E. t.notify();
F. a.notify();
G. t.interrupt();
//考点:线程方法问题
59. Click the exhibit button:

1. public class X implements Runnable (
2. private int x;
3. private int y;
4.
5. public static void main(String [] args) (
6. X that = new X();
7. (new Thread(that)) . start( );
8. (new Thread(that)) . start( );
9. )
10.
11. public synchronized void run( ) (
12. for (;(
13. x++;
14. y++;
15. System.out.printIn(“x = “ + x + “, y = “ + y);
16. )
17. )
18. )

What is the result?

A.An error at line 11 causes compilation to fail.
B.Errors at lines 7 and 8 cause compilation to fail.
C.The program prints pairs of values for x and y that might not always be the same on the same line (for example, “x=2, y=1”)
D.The program prints pairs of values for x and y that are always the same on the same line (for example, “x=1, y=1”. In addition, each value appears twice (for example, “x=1, y=1” followed by “x=1, y=1”)
E.The program prints pairs of values for x and y that are always the same on the same line (for example, “x=1, y=1”. In addition, each value appears twice (for example, “x=1, y=1” followed by “x=2s, y=2”)
//考点:循环嵌套问题
60. Which two CANNOT directly cause a thread to stop executing? (Choose Two)

A.Existing from a synchronized block
B.Calling the wait method on an object
C.Calling notify method on an object
D.Calling read method on an InputStream object
E.Calling the SetPriority method on a Thread object
//考点:线程方法问题
61. Click the exhibit button:

1. public class SyncTest{ 2. public static void main(String[] args) { 3. final StringBuffer s1= new StringBuffer(); 4. final StringBuffer s2= new StringBuffer(); 5. new Thread () { 6. public void run() { 7. synchronized(s1) { 8. s2.append(“A”); 9. synchronized(s2) { 10. s2.append(“B”); 11. System.out.print(s1); 12. System.out.print(s2); 13. } 14. } 15. } 16. }.start(); 17. new Thread() { 18. public void run() { 19. synchronized(s2) { 20. s2.append(“C”); 21. synchronized(s1) { 22. s1.append(“D”); 23. System.out.print(s2); 24. System.out.print(s1); 25. } 26. } 27. } 28. }.start(); 29. } 30. }

Which two statements are true? (Choose Two)

A. The program prints “ABBCAD”
B. The program prints “CDDACB”
C. The program prints “ADCBADBC”
D. The output is a non-deterministic point because of a possible deadlock condition
E. The output is dependent on the threading model of the system the program is running on.
//考点:线程启动方法及STRING方法问题
62. Which method in the Thread class is used to create and launch a new thread of execution?

A. run();
B. start();
C. execute();
D. run(Runnable r);
E. start(Runnable r);
F. execute(Thread t);
//考点:线程启动方法问题
63. Given:

5. String foo = “base”;
6. foo.substring(0,3);
7. foo.concat(“ket”)
8.

Type the value of foo at line 8.

Ans:

//考点:STRING类方法问题
64. Which code determines the int value foo closest to, but not greater than, a double value bar?

A. int foo = (int) Math.max(bar);
B. int foo = (int) Math.min(bar);
C. int foo = (int) Math.abs(bar);
D. int foo = (int) Math.ceil(bar);
E. int foo = (int) Math.floor(bar);
F. int foo = (int) Math.round(bar);
//考点:数学类使用问题
65. Which statement is true?

A. A flow layout can be used to position a component that should resize horizontally when the container is resized.
B. A grid layout can be used to position a component that should maintain a constant size even when the container is resized.
C. A border layout can be used to position a component that should maintain a constant size even when the container is resized.
D. The grid bag layout can be used to give a grid-like layout which differs from the normal grid in that individual rows and columns can have unique sizes.
E. If two components are placed in the same column of a grid bag layout, and one component resizes horizontally, then the other component must resize horizontally.
//考点:AWT问题
66. Given an ActionEvent, which method allows you to identify the affected Component?

A. public class getClass()
B. public Object getSource()
C. public Component getSource()
D. public Component getTarget()
E. public Component getComponent()
F. public Component getTargetComponent()
//考点:AWT问题
67. Click the exhibit button:

1. import java.awt.*; 2. 3. public class Test extends Frame { 4. public Test() { 5. add(new Label(“Hello”) ); 6. add(new TextField(“Hello”) ); 7. add(new Button(“Hello”) ); 8. pack(); 9. show(); 10. } 11. 12. public static void main(String args[]) { 13. new Test (); 14. } 15. )

What is the result?

A. The code will not compile.
B. A Window will appear containing only a Button.
C. An IllegalArgumentException is thrown at line 6.
D. A Window button will appear but will not contain the Label, TextField, or Button.
E. A Window will appear containing a Label at the top, a TextField below the Label, and a Button below the TextField.
F. A Window will appear containing a Label on the left, a TextField to the right of the Label, and a button to the right of the TextField.
//考点:AWT问题
68. Click the exhibit button:

1. class A { 2. public int getNumber(int a) { 3. return a + 1; 4. } 5. } 6. 7. class B extends A { 8. public int getNumber (int a) { 9. return a + 2 10. } 11. 12. public static void main (String args[]) { 13. A a = new B(); 14. System.out.printIn(a.getNumber(0)); 15. } 16. }

What is the result?

A. Compilation succeeds and 1 is printed.
B. Compilation succeeds and 2 is printed.
C. An error at line 8 causes compilation to fail.
D. An error at line 13 causes compilation to fail.
E. An error at line 14 causes compilation to fail.
//考点:方法覆盖及多态问题
69. Given:

1. class BaseClass{
2. private float x= 1.0f;
3. protected void setVar (float f) {x = f;}
4. }
5. class SubClass exyends BaseClass {
6. private float x = 2.0f;
7. //insert code here
8. }

Which two are valid examples of method overriding? (Choose Two)

A. void setVar(float f) {x = f;}
B. public void setVar(int f) {x = f;}
C. public void setVar(float f) {x = f;}
D. public double setVar(float f) {x = f;}
E. public final void setVar(float f) {x = f;}
F. protected float setVar() {x=3.0f; return 3.0f; }
//考点:方法覆盖问题
70. Which statement about static inner classes is true?

A. An anonymous class can be declared as static.
B. A static inner class cannot be a static member of the outer class
C. A static inner class does not require an instance of the enclosing class.
D. Instance members of a static inner class can be referenced using the class name of the static inner class.
//考点:内部类问题
71. Click the exhibit button:

1. class A { 2. public byte getNumber () { 3. return 1; 4. } 5. } 6. 7. class B extends A { 8. public short getNumber() { 9. return 2; 10. } 11. 12. public static void main (String args[]) { 13. B b = new B (); 14. System.out.printIn(b.getNumber()) 15. } 16. }

What is the result?

A. Compilation succeeds and 1 is printed.
B. Compilation succeeds and 2 is printed.
C. An error at line 8 causes compilation to fail.
D. An error at line 14 causes compilation to fail.
E. Compilation succeeds but an exception is thrown at line 14.
//考点:方法覆盖问题
72. Given:

AnInterface is an interface.
AnAdapter0 is a non-abstract, non-final class with a zero argument constructor.
AnAdapter1 is a non-abstract, non-final class without a zero argument constructor, but with a constructor that takes one int argument.

Which two construct an anonymous inner class? (Choose Two)

A. AnAdapter1 aa=new AnAdapter1(){}
B. AnAdapter0 aa=new AnAdapter0(){}
C. AnAdapter0 aa=new AnAdapter0(5){}
D. AnAdapter1 aa=new AnAdapter1(5){}
E. AnInterface a1=new AnInterface(5){}
//考点:适配器声明问题
73. Which two statements are true? (Choose Two)

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.
//考点:匿名内部类问题
74. Click the exhibit button:

1. public class Mycircle { 2. public double radius; 3. public double diameter; 4. 5. public void setRadius(double radius) 6. this.radius = radius; 7. this.diameter= radius * 2; 8. } 9. 10. public double getRadius() { 11. return radius; 12. } 13. }

Which statement is true?

A. The Mycircle class is fully encapsulated.
B. The diameter of a given MyCircle is guaranteed to be twice its radius.
C. Lines 6 and 7 should be in a synchronized block to ensure encapsulation.
D. The radius of a MyCircle object can be set without affecting its diameter.
//考点:THIS引用问题
75. You want to limit access to a method of a public class to members of the same class. Which access modifier accomplishes this objective?

A. Public
B. Private
C. Protected
D. Transient
E. No access modifier is required
//考点:关键字使用问题
76. Click the exhibit button.

ClassOne.java 1. package com.abc.pkg1; 2. public class ClassOne { 3. private char var = ‘a’; 4. char getVar() {return var;} 5. } ClassTest.java 1. package com.abc.pkg2; 2. import com.abc.pkg1.ClassOne; 3. public class ClassTest extends ClassOne { 4. public static void main(String[]args) { 5. char a = new ClassOne().getVar(); 6. char b = new ClassTest().getVar(); 7. } 8. }

What is the result?

A. Compilation will fail.
B. Compilation succeeds and no exceptions are thrown.
C. Compilation succeeds but an exception is thrown at line 5 in ClassTest.java.
D. Compilation succeeds but an exception is thrown at line 6 in ClassTest.java.
//考点:类实例化问题问题
77. Given:

1. public class ArrayTest {
2. public static void main (String[]args) {
3. float f1[], f2[];
4. f1 = new float [10];
5. f2 = f1;
6. System.out.printIn (“f2[0]=” + f2[0]);
7. }
8. }

What is the result?

A. It prints f2[0] = 0.0.
B. It prints f2[0] = NaN.
C. An error at line 5 causes compile to fail.
D. An error at line 6 causes compile to fail.
E. An error at line 6 causes an exception at runtime.
//考点:原始数据类型默认值问题
78. Which two statements are true regarding the creation of a default constructor? (Choose Two)

A. The default constructor initializes method variables.
B. The compiler always creates a default constructor for every class.
C. The default constructor invokes the no-parameter constructor of the superclass.
D. The default constructor initializes the instance variables declared in the class.
E. When a class has only constructors with parameters, the compiler does not create a default constructor.
//考点:默认构造方法问题
79. Click the exhibit button:

1. class super { 2. public int getLength() {return 4;} 3. } 4. 5. public class Sub extends Super { 6. public long getLength() {return 5;} 7. 8. public static void main (String[]args) { 9. super sooper = new Super (); 10. Sub sub = new Sub(); 11. System.out.printIn( 12. sooper.getLength()+ “,” + sub.getLength() }; 13. } 14. }

What is the output?

A. 4, 4
B. 4, 5
C. 5, 4
D. 5, 5
E. the code will not compile
//考点:方法覆盖问题
80. Given:

1. public abstract class Test {
2. public abstract void methodA();
3.
4. public abstract void methodB()
5. {
6. System.out.printIn(“Hello”);
7. }
8. }

Which three changes (made independently) allow the code to compile? (Choose Three)

A. Add a method body to methodA.
B. Replace lines 5-7 with a semicolon (“.”).
C. Remove the abstract qualifier from the declaration of Test.
D. Remove the abstract qualifier from the declaration of methodB.
E. Remove the abstract qualifier from the declaration of methodA.
F. Remove methodB in its entirely and change class o interface in line 1.
//考点:抽象类及抽象方法问题
81. Which determines if “prefs” is a directory and exists on the file system?

A.Boolean exists=Directory.exists (“prefs”);
B.Boolean exists=(new File(“prefs”)).isDir();
C.Boolean exists=(new Directory(“prefs”)).exists();
D.Boolean exists=(new File(“prefs”)).isDirectory();
E.Boolean exists=true;
Try{
Directory d = new Directory(“prefs”);
}
catch (FileNotFoundException e) {
exists = false;
}
//考点 Blush

/O问题
82. Which two create an InputStream and open file the “file.txt” for reading? (Choose Two)

A. InputStream in=new FileReader(“file.txt”);
B. InputStream in=new FileInputStream(“file.txt”);
C. InputStream in=new InputStreamFileReader (“file.txt”, “read”);
D. FileInputStream in=new FileReader(new File(“file.txt”));
E. FileInputStream in=new FileInputStream(new File(“file.txt”));
//考点 Blush

/O问题
83. Which two construct an OutputSream that appends to the file “file.txt”? (Choose Two)

A. OutputStream out=new FileOutputStream(“file.txt”);
B. OutputStream out=new FileOutputStream(“file.txt”, “append”);
C. FileOutputStream out=new FileOutputStream(“file.txt”, true);
D. FileOutputStream out=new FileOutputStream(new file(“file.txt”));
E. OutputStream out=new FileOutputStream(new File(“file.txt”)true);
//考点 Blush

/O问题
84. Which constructs a BufferedInputStream?

A. New BufferedInputStream(“in.txt”);
B. New BufferedInputStream(new File(“in.txt”));
C. New BufferedInputStream(new Writer(“in.txt”));
D. New BufferedInputStream(new Writer(“in.txt”));
E. New BufferedInputStream(new InputStream(“in.txt”));
F. New BufferedInputStream(new FileInputStream(“in.txt”));
//考点 Blush

/O问题
85. Which is a valid identifier?

A. false
B. default
C. _object
D. a-class
//考点:标识符问题
86. Click the exhibit button:

1. package foo; 2. 3. import java.util.Vector; 4. 5. private class MyVector extends Vector { 6. int i = 1; 7. public MyVector() { 8. i = 2; 9. } 10. } 11. 12. public class MyNewVector extends MyVector { 13. public MyNewVector () { 14. i = 4; 15. } 16. public static void main (String args []) { 17. MyVector v = new MyNewVector(); 18. } 19. }

The file MyNewVector.java is shown in the exhibit.

What is the result?

A. Compilation will succeed
B. Compilation will fail at line 5
C. Compilation will fail at line 6
D. Compilation will fail at line 14
E. Compilation will fail at line 17
//考点:关键字使用问题
87. Given:

1. public class Test {
2. public static void main (String[]args) {
3. String foo = args[1];
4. String bar = args[2];
5. String baz = args[3];
6. System.out.printIn(“baz = ” + baz);
7. }
8. }

And the output:
Baz = 2

Which command line invocation will produce the output?

A. java Test 2222
B. java Test 1 2 3 4
C. java Test 4 2 4 2
D. java Test 4 3 2 1
//考点:主方法及数组下标值得问题
88. Given:

8. int index = 1;
9. String [] test = new String[3];
10. String foo = test[index];

What is the result?

A. foo has the value “”
B. foo has the value null
C. an exception is thrown
D. the code will not compile
//考点:数组下标值问题
89. Given:

1. public interface Foo{
2. int k = 4;
3. }

Which three are equivalent to line 2? (Choose Three)

A.final int k = 4;
B.public int k = 4;
C.static int k = 4;
D.private int k = 4;
E.abstract int k = 4;
F.volatile int k = 4;
G.transient int k = 4;
H.protected int k = 4;
//考点:接口中常量默认的存取控制符号问题
90. Given:

1. public class foo {
2. static String s;
3. public static void main (String[]args) {
4. system.out.printIn (“s=” + s);
5. }
6. }

What is the result?

A. The code compiles and “s=” is printed.
B. The code compiles and “s=null” is printed.
C. The code does not compile because string s is not initialized.
D. The code does not compile because string s cannot be referenced.
E. The code compiles, but a NullPointerException is thrown when toString is called.
//考点:引用型传址问题
91. Which of the following two are valid declarations of a char? (Choose Two)

A.char ch = “a”;
B.char ch = ‘\’ ‘;
C.char ch = ‘cafe’;
D.char ch = “cafe”;
E.char ch = ‘\ucafe’;
F.char ch = ‘\u10100’;
G.char ch = (char) true;
//考点:原始数据类型取值范围问题
92. Given:

1. String foo = “blue”;
2. Boolean[]bar = new Boolean [1];
3. if (bar[0]) {
4. foo = “green”;
5. }

What is the result?

A.foo has the value of “”
B.foo has the value of null
C.foo has the value of “blue”
D.foo has the value of “green”
E.an exception is thrown
F.the code will not compile
//考点:布尔型默认值问题
93. Click the exhibit button:

1. public class X { 2. public static void main (String[]args) { 3. String s1 = new String (“true”); 4. Boolean b1 = new Boolean (true); 5. if (s2.equals(b1)) { 6. System.out.printIn(“Equal”); 7. } 8. } 9. }

What is the result?

A. The program runs and prints nothing.
B. The program runs and prints “Equal.”
C. An error at line 5 causes compilation to fail.
D. The program runs but aborts with an exception.
//考点:EQUALS方法使用问题
94. Given:

1. public class Foo {
2. public static void main (String []args) {
3. int i = 1;
4. int j = i++;
5. if ((i>++j) && (i++ ==j)) {
6. i +=j;
7. }
8. }
9. }

What is the final value of i?

A.1
B.2
C.3
D.4
E.5
//考点:循环嵌套问题
95. Click the exhibit button:

1. public class X { 2. public static void main (String[]args) { 3. string s = new string (“Hello”); 4. modify Moon

; 5. System.out.printIn Moon

; 6. } 7. 8. public static void modify (String s) { 9. s += “world!”; 10. } 11. }

What is the result?

A.The program runs and prints “Hello”.
B.An error causes compilation to fail.
C.The program runs and prints “Hello world!”.
D.The program runs but aborts with an exception.
//考点:引用型传址问题
96. Which two are equivalent? (Choose Two)

A.16>4
B.16/2
C.16*4
D.16>>2
E.16/2^2
F.16>>>2
//考点:操作符号问题
97. Click the exhibit button

1. public class X { 2. public static void main (String[]args) { 3. int [] a = new int [1] 4. modify Angel

; 5. System.out.printIn(a[0]); 6. } 7. 8. public static void modify (int[] a) { 9. a[0] ++; 10. } 11. }

What is the result?

A. The program runs and prints “0”.
B. The program runs and prints “1”.
C. The program runs but aborts with an exception.
D. An error “possible undefined variable” at line 4 causes compilation to fail.
E. An error “possible undefined variable” at line 9 causes compilation to fail.
//考点:STATIC修饰符及原始数据类型默认值问题
98. Given:

13. public class Foo {
14. public static void main (String [] args) {
15. StringBuffer a = new StringBuffer (“A”);
16. StringBuffer b = new StringBuffer (“B”);
17. operate (a,b);
18. system.out.printIn{a + “,” +b};
19. )
20. static void operate (StringBuffer x, StringBuffer y) {
21. y.append {x};
22. y = x;
23. )
24. }

What is the result?

A.The code compiles and prints “A,B”.
B.The code compiles and prints “A, BA”.
C.The code compiles and prints “AB, B”.
D.The code compiles and prints “AB, AB”.
E.The code compiles and prints “BA, BA”.
F.The code does not compile because “+” cannot be overloaded for stringBuffer.
//考点:STRINGBUFFER类使用问题
99. Given:

1. public class X {
2. public static void main (String[] args) {
3. byte b = 127;
4. byte c = 126;
5. byte d = b + c;
6. }
7. }

Which statement is true?
//考点:原始数据类型取值范围问题
A.Compilation succeeds and d takes the value 253.
B.Line 5 contains an error that prevents compilation.
C.Line 5 throws an exception indicating “Out of range”.
D.Line 3 and 4 contain error that prevent compilation.
E.The compilation succeeds and d takes the value of 1.

100. Given:

1. public class WhileFoo {
2. public static void main (String []args) {
3. int x= 1, y = 6;
4. while (y--) {x--;}
5. system.out.printIn(“x=” + x “y =” + y);
6. }
7. }

What is the result?

A.The output is x = 6 y = 0
B.The output is x = 7 y = 0
C.The output is x = 6 y = -1
D.The output is x = 7 y = -1
E.Compilation will fail
//考点:操作符号与循环嵌套组合问题
101. Which statement is true?

A. The Error class is a RuntimeException.
B. No exceptions are subclasses of Error.
C. Any statement that may throw an Error must be enclosed in a try block.
D. Any statement that may throw an Exception must be enclosed in a try block.
E. Any statement that may thro a runtimeException must be enclosed in a try block.
//考点:RuntimeException 是否需要捕捉问题
102. Click the exhibit button:

1. int I=1, j=0 2. 3. switch Light Bulb

{ 4. case 2: 5. j+=6; 6. 7. case 4: 8. j+=1; 9. 10. default: 11. j +=2; 12. 13. case 0: 14. j +=4; 15. } 16.

What is the value of j at line 16?

A. 0
B. 1
C. 2
D. 4
E. 6
//考点:原始数据类型传值问题
103. Given:

1. switch Light Bulb

{
2. default:
3. System.out.printIn(“Hello”);
4. )

What is the acceptable type for the variable i?

A.byte
B.long
C.float
D.double
E.object
F.A and B
G.C and D
//考点:传参数问题
104. You need to store elements in a collection that guarantees that no duplicates are stored. Which two interfaces provide that capability? (Choose Two)

A. java.util.Map
B. java.util.Set
C. java.util.List
D. java.util.StoredSet
E. java.util.StoredMap
F. java.util.Collection
//考点:collection 类问题
105. Which statement is true for the class java.util.ArrayList?

A. The elements in the collection are ordered.
B. The collection is guaranteed to be immutable.
C. The elements in the collection are guaranteed to be unique.
D. The elements in the collection are accessed using a unique key.
E. The elements in the collections are guaranteed to be synchronized.
//考点:collection 类问题
106. Click the exhibit button:

1. public class X implements Runnable( 2. private int x; 3. private int y; 4. 5. public static void main(String[]args) 6. X that = new X(); 7. (new Thread(that)).start(); 8. (new Thread(that)).start(); 9. ) 10. 11. public void run() ( 12. for (; ( 13. x++; 14. y++; 15. System.out.printIn(“x=” + x + “, y = ” + y); 16. ) 17. ) 18. )

What is the result?

A. Errors at lines 7 and 8 cause compilation to fail.
B. The program prints pairs of values for x and y that might not always be the same on the same line (for example, “x=2, y=1”).
C. The program prints pairs of values for x and y that are always the same on the same line (for example, “x=1, y=1”. In addition, each value appears twice (for example, “x=1, y=1” followed by “x=1, y=1”).
D. The program prints pairs of values for x and y that are always the same on the same line (for example, “x=1, y=1”. In addition, each value appears only for once (for example, “x=1, y=1” followed by “x=2, y=2”).
//考点:线程类方法使用使用问题
107. Given:

1. public class SyncTest {
2. private int x;
3. private int y;
4. public synchronized void setX (int i) (x=1 Wink

5. public synchronized void setY (int i) (y=1 Wink

6. public synchronized void setXY(int 1)(set X Light Bulb

; setY

7. public synchronized Boolean check() (return x !=y Wink

8. )

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 set separately.
//考点:SYNCHRONIZED关键字使用问题
108. Which is a method of the MouseMotionListener interface?

A. Public void mouseDragged(MouseEvent)
B. Public boolean mouseDragged(MouseEvent)
C. Public void mouseDragged(MouseMotionEvent)
D. Public boolean MouseDragged(MouseMotionEvent)
E. Public boolean mouseDragged(MouseMotionEvent)
//考点:AWT使用问题
109. Given:

4. String foo = “base”;
5. foo.substring(0,3);
6. foo.concat(“ket”);
7. foo += “ball”;
8.

Type the value of foo at line 8.
//考点:STRING类方法问题
110. Given:

1. public class Test {
2. public static void leftshift(int i, int j) {
3. i<<=j;
4. }
5. public static void main(String args[]) {
6. int i = 4, j = 2;
7. leftshift(i, j);
8. System.out.printIn Light Bulb

;
9. }
10. }

What is the result?

A.2
B.4
C.8
D.16
E.The code will not compile
//考点:操作符号使用问题
111. Given:

1. public class Foo {
2. private int val;
3. public foo(int v) (val = v Wink

}
4. public static void main (String [] args) {
5. Foo a = new Foo (10);
6. Foo b = new Foo (10);
7. Foo c = a;
8. int d = 10;
9. double e = 10.0;
10. }
11. }

Which three logical expressions evaluate to true? (Choose Three)

A.(a ==c)
B.(d ==e)
C.(b ==d)
D.(a ==b)
E.(b ==c)
F.(d ==10.0)
//考点:==使用问题
112. Click the exhibit button:

1. public class X { 2. private static int a; 3. 5. public static void main (String[] args) { 6. modify Angel

; 7. } 8. 9. public static void modify (int a) { 10. a++; 11. } 12. }

What is the result?

A. The program runs and prints “0”.
B. The program runs and prints “1”.
C. The program runs but aborts with an exception.
D. En error “possible undefined variable” at line 5 causes compilation to fail.
E. En error “possible undefined variable” at line 10 causes compilation to fail.
//考点:STATIC变量使用问题问题
113. Click the exhibit button:

1. public class Test { 2. public static void replaceJ(string text) { 3. text.replace (‘j’, ‘l’); 4. } 5. 6. public static void main(String args[]) { 7. string text = new String (“java”) 8. replaceJ(text); 9. system.out.printIn(text); 10. } 11. }

What is the result?

A. The program prints “lava”.
B. The program prints “java”.
C. An error at line 7 causes compilation to fail.
D. Compilation succeeds but the program throws an exception.
//考点:STRING类方法问题
114. Which two are equivalent? (Choose Two)

A.3/2
B.3<2
C.3*4
D.3<<2
E.3*2^2
F.3<<<2
//考点:操作符号使用问题
115. What is the numerical range of a char?

A. 0 . . . 32767
B. 0 . . . 65535
C. -256 . . . 255
D. -32768 . . . 32767
E. range is platform dependent
//考点:原始数据类型取值范围问题
116. Given:

1. public class Test {
2. public static void main (String []args) {
3. unsigned byte b = 0;
4. b--;
5.
6. }
7. }

What is the value of b at line 5?

A.-1
B.255
C.127
D.compilation will fail
E.compilation will succeed but the program will throw an exception at line 4
//考点:关键字问题
117. Given:

1. public class Foo {
2. public void main (String [] args) {
3. system.out.printIn(“Hello World.”);
4. }
5. }

What is the result?

A.An exception is thrown.
B.The code does not compile.
C.“Hello World.” is printed to the terminal.
D.The program exits without printing anything.
//考点:实例化问题
118. Given:

1. //point X
2. public class foo (
3. public static void main (String[]args) throws Exception {
4. java.io.printWriter out = new java.io.PrintWriter (
5. new java.io.outputStreamWriter (System.out), true;
6. out.printIn(“Hello”);
7. }
8. }

Which statement at PointX on line 1 allows this code to compile and run?

A. import java.io.*;
B. include java.io.*;
C. import java.io.PrintWriter;
D. include java.io.PrintWriter;
E. no statement is needed.
//考点:JAVA原文件声明顺序问题
119. Which will declare a method that is available to all members of the same package and can be referenced without an instance of the class?

A.abstract public void methoda();
B.public abstract double methoda();
C.static void methoda(double d1){}
D.public native double methoda() {}
E.protected void methoda(double d1) {}
//考点:存取控制符问题
120. Which type of event indicates a key pressed on a java.awt.Component?

A. KeyEvent
B. KeyDownEvent
C. KeyPressEvent
D. KeyTypedEvent
E. KeyPressedEvent
//考点:AWT事件处理
121. Click the exhibit button:

1. import java.awt.*; 2. 3. public class X extends Frame { 4. public static void main (String [] args) { 5. X x = new X(); 6. x.pack(); 7. x.setVisible(true); 8. } 9. 10. public X() { 11. setLayout (new BordrLayout()); 12. Panel p = new Panel (); 13. add(p, BorderLayout.NORTH); 14. Button b = new Button (“North”); 15. p.add Beer

: 16. Button b = new Button (“South”); 17. add(b1, BorderLayout.SOUTH): 18. } 19. }
//考点:布局管理器问题
Which two statements are true? (Choose Two)

A. The buttons labeled “North” and “South” will have the same width
B. The buttons labeled “North” and “South” will have the same height
C. The height of the button labeled “North” can very if the Frame is resized
D. The height of the button labeled “South” can very if the Frame is resized
E. The width of the button labeled “North” is constant even if the Frame is resized
F. The width of the button labeled “South” is constant even if the Frame is resized
//考点:布局管理器问题
122. How can you create a listener class that receives events when the mouse is moved?

A.By extending MouseListener.
B.By implementing MouseListener.
C.By extending MouseMotionListener.
D.By implementing MouseMotionListener.
E.Either by extending MouseMotionListener or extending MouseListener.
F.Either by implementing MouseMotion Listener or implementing MouseListener.
//考点:接口使用问题
123. Which statement is true?

A. A grid bag layout can position components such that they span multiple rows and/or columns.
B. The “North” region of a border layout is the proper place to locate a menuBar component in a Frame.
C. Components in a grid bag layout may either resize with their cell, or remain centered in that cell at their preferred size.
D. A border layout can be used to position a component that should maintain a constant size even when the container is resized.
//考点:布局管理器问题
124. 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 this objective?

A. Public
B. Private
C. Protected
D. Transient
E. No access modifier is required
//考点:关键字使用问题
125. Which two statements are true regarding the creation of a default constructor? (Choose Two)

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.
//考点:默认构造方法问题
126. Given:

1. public class OuterClass {
2. private double d1 1.0;
3. //insert code here
4. }

You need to insert an inner class declaration at line2. Which two inner class declarations are valid? (Choose Two)

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();
}
//考点:内部类声明问题
127. Which two declarations prevent the overriding of a method? (Choose Two)

A. final void methoda() {}
B. void final methoda() {}
C. static void methoda() {}
D. static final void methoda() {}
E. final abstract void methoda() {}
//考点:方法覆盖问题
128. Given:

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
//考点:内部类的变量使用问题
129. Which two create an instance of an array? (Choose Two)

A. int[] ia = new int [15];
B. float fa = new float [20];
C. char[] ca = “Some String”;
D. Object oa = new float[20];
E. Int ia [][

yamakasy edited on 2002-08-03 12:21

话题树型展开

人气	标题	作者	字数	发贴时间
14853	[经典]JAVA---SCJP考题分析	smartzhao	60352	2002-08-03 03:10
13221	回复：经典JAVA---SCJP考题分析	smartzhao	1451	2002-08-03 03:12
11945	回复： [经典]JAVA---SCJP考题分析	jx_ceo	46	2002-09-06 02:14
12173	回复： [经典]JAVA---SCJP考题分析	jmd7	93	2002-09-06 09:37
12362	回复： [经典]JAVA---SCJP考题分析	bluemud	115	2002-09-11 16:06
12798	回复：经典JAVA---SCJP考题分析	smartzhao	8061	2002-08-03 03:13
12488	回复：经典JAVA---SCJP考题分析	yamakasy	118	2002-08-03 10:13
12904	回复：回复：经典JAVA---SCJP考题分析	smartzhao	229	2002-08-03 10:57
13067	回复： [经典]JAVA---SCJP考题分析	Biubiu	6	2002-08-04 10:16
11992	回复： [经典]JAVA---SCJP考题分析	wunglee	571	2002-08-18 00:01
12239	回复：回复： [经典]JAVA---SCJP考题分析	smartzhao	709	2002-08-18 00:52
11948	回复：回复： [经典]JAVA---SCJP考题分析	淡淡的忧伤	678	2002-08-19 21:33
11968	回复： [经典]JAVA---SCJP考题分析	wunglee	102	2002-08-19 20:09
12186	回复： [经典]JAVA---SCJP考题分析	jmd7	500	2002-08-19 20:41
12182	回复： [经典]JAVA---SCJP考题分析	jx_ceo	1277	2002-09-05 21:38
12165	回复： [经典]JAVA---SCJP考题分析	jmd7	305	2002-09-06 01:04

已读帖子

新的帖子

被删除的帖子