A. If the hashCode values are different, the objects might be equal.
B. If the hashCode values are the same, the object must be equal.
C. If the hashCode values are the same, the objects might be equal.
D. If the hashCode values are different, the objects must be unequal.
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A. run
B. import
C. default
D. implement
11. public static void main(String[] args) {
12. Object obj = new Object() {
13. public int hashCode() {
14. returns 42;
15. }
16. };
17. System.out.println(obj.hashCode());
18. }
What is the result? ()
A. 42
B. An exception is thrown at runtime.
C. Compilation fails because of an error on line 12.
D. Compilation fails because of an error on line 16.
E. Compilation fails because of an error on line 17.
A. void run()
B. public void run()
C. public void start()
D. void run(int priority)
E. public void run(int priority)
F. public void start(int priority)
public class Test {
public static void main( String[] args) {
String foo = args[1];
String bar = args[2];
String baz = args[3];
System.out.println(“baz = “ + baz);
}
}
And the command line invocation: java Test red green blue
What is the result?()
A. baz =
B. baz = null
C. baz = blue
D. Compilation fails.
E. An exception is thrown at runtime.
public class Test {
private static int[] x;
public static void main(String[] args) {
System.out.println(x[0]);
}
}
What is the result?()
A. 0
B. null
C. Compilation fails.
D. A NullPointerException is thrown at runtime.
E. An ArrayIndexOutOfBoundsException is thrown at runtime.
A. float f = 1F;
B. float f = 1.0.;
C. float f = ‘1’;
D. float f = “1”;
E. float f = 1.0d;
// Point X
public class foo {
public static void main(String[] args) throws Exception {
jave.io.PrintWriter out = new jave.io.PrintWriter(
new jave.io.OutputStreamWriter(System.out), true);
out.println(“Hello”);
}
}
Which statement at Point X on line 1 is required to allow this code to compile?()
A. No statement is required.
B. import jave.io.*;
C. include java.io.*;
D. import jave.io.PrintWriter;
E. include java.io.PrintWriter;
ArraryList a = new ArrayList();
a.add(“Alpha”);
a.add(“Bravo”):
a.add(“Charlie”);
a.add(“Delta”);
Iterator iter = a.iterator();
Which two, added at line 17, print the names in the ArrayList in alphabetical order?()
A. for (int i=0; i< a.size(); i++) System.out.println(a.get(i)));
B. for (int i=0; i< a.size(); i++) System.out.println(a[i]);
C. while( iter.hasNext() ) System.out.println(iter.next()) ;
D. for (int i=0, i< a.size(); i++) System.out.println(iter[i]);
E. for (int i=0; i< a.size(); i++) System.out.println(iter.get(i));
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.
public class A extends Thread {
A() {
setDaemon(true);
}
public void run() {
(new B()).start();
try {
Thread.sleep(60000);
} catch (InterruptedException x) {}
System.out.println(“A done”);
}
class B extends Thread {
public void run() {
try {
Thread.sleep(60000);
} catch (InterruptedException x) {}
System.out.println(“B done”);
}
}
public static void main(String[] args) {
(new A()).start();
}
}
What is the result?()
A. A done
B. B done
C. A done B done
D. B done A done
E. There is no exception that the application will print anything.
F. The application outputs “A done” and “B done”, in no guaranteed order.
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