StackOverflowError
NullPointerException
NumberFormatException
IllegalArgumentException
ExceptionlnlnitializerError
第1题:
3下面程序段的输出结果为( )。package test;public class ClassA{ int x=20; static int y=6; public static void main(String args[]) { ClassB b=new ClassB(); b.go(10); System.out.println("x="+b.x); }}class ClassB{ int x; void go(int y) { ClassA a=new ClassA(); x=a.y; }}
A.x=10
B.x=20
C.x=6
D.编译不通过
第2题:
11. class Converter { 12. public static void main(String[] args) { 13. Integer i = args[0]; 14. int j = 12; 15. System.out.println(”It is “ + (j==i) + “that j==i.”); 16. } 17. } What is the result when the programmer attempts to compile the code and run it with the command java Converter 12?()
第3题:
下面程序段的输出结果为 package test; public class ClassA { int x=20; static int y=6; public static void main(String args[]) { ClassB b=new ClassB(); b.go(10); System.out.println("x="+b.x); } } class ClassB { int x; void go(int y) { ClassA a=new ClassA(); x=a.y; } }
A.x=10
B.x=20
C.x=6
D.编译不通过
第4题:
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 (a); 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?()
第5题:
class ClassA { public int numberOfinstances; protected ClassA(int numberOfinstances) { this.numberOflnstances = numberOfinstances; } } public class ExtendedA extends ClassA { private ExtendedA(int numberOfinstances) { super(numberOflnstances); } public static void main(String[] args) { ExtendedA ext = new ExtendedA(420); System.out.print(ext.numberOflnstances); } } Which is true?()
第6题:
10. public class ClassA { 11. public void count(int i) { 12. count(++i); 13. } 14. } And: 20. ClassA a = new ClassA(); 21. a.count(3); Which exception or error should be thrown by the virtual machine?()
第7题:
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 23?()
第8题:
下面程序段的输出结果为( )。 package test; public class ClassA { int x=20: static int y=6; public static void main(String args[]) { ClassB b=new ClassB; go(10); System.out.println("x="+b.x); } } class ClassB { int X; void go(int y) { ClassA a=new ClassA; x=a.Y ; } }
A.x=10
B.x=20
C.x=6
D.编译不通过
第9题:
11.classA { 12. public void process() { System.out.print(”A “); } } 13. class B extends A { 14. public void process() throws RuntimeException { 15. super.process(); 16. if (true) throw new RuntimeException(); 17. System.out.print(“B”); }} 18. public static void main(String[] args) { 19. try { ((A)new B()).process(); } 20. catch (Exception e) { System.out.print(”Exception “); } 21. } What is the result?()
第10题:
10. class Inner { 11. private int x; 12. public void setX( int x) { this.x = x; } 13. public int getX() { return x; } 14. } 15. 16. class Outer { 17. private Inner y; 18. public void setY( Inner y) { this.y = y; } 19. public Inner getY() { return y; } 20. } 21. 22. public class Gamma { 23. public static void main( String[] args) { 24. Outer o = new Outer(); 25. Inner i = new Inner(); 26.int n=10; 27. i.setX(n); 28. o.setY(i); 29. // insert code here 30. System.out.println( o.getY().getX()); 31. } 32. } Which three code fragments, added individually at line 29, produce the output 100?()