Certified Java Programmer Mock Exam

Question 1

interface A {
  void m1();            // 1
  public void m2();     // 2
  protected void m3();  // 3
  private void m4();    // 4
}

What is the result of attempting to compile the code?

Question 2

interface A {  
  protected int e = 5;              // 1
  private int f = 6;                // 2
  volatile int g = 7;               // 3
  transient int h = 8;              // 4
}

Which of the field declarations result in a compile-time error?

Question 3

Which of the following are modifiers that can be applied to an interface that is not a member of an enclosing class?

Question 4

interface A {
  void m1();              // 1
}
class B implements A {
  public void m1() {}     // 2
}
class C implements A {
  protected void m1() {}  // 3
}
class D implements A {
  private void m1() {}    // 4
}
class E implements A {
  void m1() {}            // 5
}

What is the result of attempting to compile the code?

Question 5

Which of the following are true statements?

Question 6

interface F {abstract void main(String[] args);}      // 1
interface G {synchronized void main(String[] args);}  // 2
interface H {final void main(String[] args);}         // 3
interface I {native void main(String[] args);}        // 4

Which interface declarations generate a compile-time error?

Question 7

Which of the following are true statements?

Question 8

Which of the following modifiers can be applied to a class that is declared within an enclosing interface?

Question 9

Which of the following are modifiers that can be applied to a member interface?

Question 10

1. class A {void m1(String s1) {}}
2. class B extends A {
3.   void m1(String s1) {}
4.   void m1(boolean b) {}
5.   void m1(byte b) throws Exception {}
6.   String m1(short s) {return new String();}
7.   private void m1(char c) {}
8.   protected void m1(int i) {}
9. }

What is the result of attempting to compile and run the above program?

Question 11

Which of the following are modifiers that can be applied to a member interface?

Question 12

Which of the following are true statements?

Question 13

class R {
  private void printS1(){System.out.print("R.printS1 ");}
  protected void printS2() {System.out.print("R.printS2 ");}
  protected void printS1S2(){printS1();printS2();}
}

class S extends R {
  private void printS1(){System.out.print("S.printS1 ");}
  protected void printS2(){System.out.print("S.printS2 ");}
  public static void main(String[] args) {
    new S().printS1S2();
  }
}

What is the result of attempting to compile and run the above program?

Question 14

class A {
  String s1 = "A.s1";
  String s2 = "A.s2";
}

class B extends A {
  String s1 = "B.s1";
  public static void main(String args[]) {
    B x = new B();
    A y = (A)x;
    System.out.println(x.s1+" "+x.s2+" "+y.s1+" "+y.s2);
  }
}

What is the result of attempting to compile and run the above program?

Question 15

interface Z {void m1();}  // 1
class A implements Z {void m1() {}} // 2
class B implements Z {public void m1() {}} // 3
abstract class C implements Z {public abstract void m1();} // 4

Compile-time errors are generated at which lines?

Question 16

interface A {
  String m1();
  class B implements A {public String m1() {return "B";}}
}
class C implements A {
  public String m1() {return "C";}
  class D extends B {public String m1() {return "D";}}
}
class E {
  public static void main(String[] args) {
    // Insert statement here.
  }
}

Which of the following statements could be inserted into the program to print the String ""D"?

Question 17

class SuperA {String s1="SuperA";}
class SuperB {String s1="SuperB";}
class A extends SuperA {
  String s1="A";
  class B extends SuperB {  // 1
    String s1="B";
    void m1() {
      System.out.print(this.s1 + ","); // 2
      System.out.print(super.s1 + ","); // 3
      System.out.print(A.this.s1 + ","); // 4
      System.out.print(A.super.s1); // 5
    }
  }
  public static void main (String[] args) {
    new A().new B().m1(); // 6
  }
}

What is the result of attempting to compile and run the above program?