10. public class SuperCaic { 11. protected static int multiply(int a, int b) { return a * b; } 12. } and: 20. public class SubCalc extends SuperCalc { 21. public static int multiply(int a, int b) { 22. int c = super.multiply(a, b); 23. return c; 24. } 25. } and: 30. SubCalc sc = new SubCalc(); 31. System.out.println(sc.multiply(3,4)); 32. System.out.println(SubCalc.multiply(2,2)); What is the result?()
public class Foo { public static void main (String args) { int i = 1; int j = i++; if ((i>++j) && (i++ ==j)) { i +=j; } } } What is the final value of i?()
public class Test { public static void replaceJ(string text) { text.replace (‘j’, ‘l’); } public static void main(String args[]) { string text = new String (“java”) replaceJ(text); system.out.printIn(text); } } What is the result?()
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?()
public class TestApp{ public static void main(String[] args){ try{ int i = 0; int j = 1 / i; String myname=null; if(myname.length()>2) System.out.print(“1”); }catch(NullPointerException e){ System.out.print(“2”); } catch(Exception e){ System.out.print(“3”); } } } 上述程序运行后的输出是哪项?()
public class TestString 1 { public static void main(String[] args) { String str = “420”; str += 42; System.out.print(str); } } What is the output?()
public class TwoThreads { private static Object resource = new Object(); private static void delay(long n) { try { Thread.sleep(n); } catch (Exception e) { System.out.print(”Error “); } } public static void main(String[] args) { System.out.print(”StartMain “); new Thread1().start(); delay(1000); Thread t2 = new Thread2(); t2.start(); delay(1000); t2.interrupt delay(1000); System.out.print(”EndMain “); } static class Thread 1 extends Thread { public void run() { synchronized (resource) { System.out.print(”Startl “); delay(6000); System.out.print(”End1 “); } } } static class Thread2 extends Thread { public void run() { synchronized (resource) { System.out.print(”Start2 “); delay(2000); System.out.print(”End2 “); } } } } Assume that sleep(n) executes in exactly m milliseconds, and all other code executes in an insignificant amount of time. What is the output if the main() method is run?()
Which statements concerning the correlation between the inner and outer instances of non-static inner classes are true?()
An AIX server is configured with a static IP address but the system administrator wants the server to give out IP addresses for clients who want to use the dynamic host configuration protocol instead of static IP addresses.How is this accomplished?()
1. class Calc { 2. public static void main(String [] args) { 3. try { 4. int x = Integer.parseInt("42a"); 5. //insert code here 6. System.out.print("oops "); 7. } 8. } 9. } 下面哪两行分别插入到第五行,会导致输出“oops”?()