Certified Java Programmer Mock Exam

Question 1

class GRC4 {public static void main(String[] args) {}} // 1
class GRC5 {public static void main(String []args) {}} // 2
class GRC6 {public static void main(String args[]) {}} // 3

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

Question 2

class MCZ27 {
  public static void main (String[] args) {
    char a = '\f';  // 1
    char b = '\n';  // 2
    char c = '\r';  // 3
    char d = '\l';  // 4
    char e = '\\';  // 5
}}

A compile-time error is generated at which line?

Question 3

class GFC402 {
  static int x=1;
  void m1(int i) {x++; i++;}
  public static void main (String[] args) {
    int y=3; m1(y);
    System.out.println(x + "," + y);
}}

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

Question 4

Which of the following modifiers can be applied to a constructor?

Question 5

Which of the following modifiers can be applied to the declaration of a field?

Question 6

Which of the following modifiers can not be applied to a method?

Question 7

class JSC202 {
  static byte m2() {final short s = 2; return s;}  // 1 
  static byte m4(final short s) {return s;}        // 2
  public static void main(String[] args) {
    short s = 4;
    System.out.print(""+m2()+m4(s));
}}

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

Question 8

Which of the follow statements is true.

Question 9

Which of the follow are true statements.

Question 10

class JMM102 {
  public static void main(String args[]) {
    for (int i = 0; i<5 ;i++) {
      switch(i) {
        case 0: System.out.print("v ");break;
        case 1: System.out.print("w ");
        case 2: System.out.print("x ");break;
        case 3: System.out.print("y ");
        case 4: System.out.print("z ");break;
        default: System.out.print("d ");
}}}}

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

Question 11

class A {
  public static void main (String[] args) {
    Object error = new Error();
    Object runtimeException = new RuntimeException();
    System.out.print((error instanceof Exception) + ",");
    System.out.print(runtimeException instanceof Exception);
}}

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

Question 12

// Class A is declared in a file named A.java.
package com.dan.chisholm;
public class A {
  public void m1() {System.out.print("A.m1, ");}
  protected void m2() {System.out.print("A.m2, ");}
  private void m3() {System.out.print("A.m3, ");}
  void m4() {System.out.print("A.m4, ");}
}
// Class D is declared in a file named D.java.
package com.dan.chisholm.other;
import com.dan.chisholm.A;
public class D {
  public static void main(String[] args) {
    A a = new A();
    a.m1();  // 1
    a.m2();  // 2
    a.m3();  // 3
    a.m4();  // 4
}}

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

Question 13

Which of the following statements are true?

Question 14

class JJF2 {
  public static void main (String args[]) {
    System.out.print(Short.MIN_VALUE+",");
    System.out.print(Short.MAX_VALUE);
}}

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

Question 15

class EBH202 {
  static boolean a, b, c;
  public static void main (String[] args) {
    boolean x = (a = true) || (b = true) && (c = true);
    System.out.print(a + "," + b + "," + c);
}}

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

Question 16

class GFC101 {
  public static void main(String[] args) {
    byte b1 = -128;    // 1
    byte b2 = 128;     // 2
    short s1 = -32769; // 3
    short s2 = 32767;  // 4
    char c1 = 0;       // 5
    char c2 = 65536;   // 6
}}

Compile-time errors are generated at which lines?

Question 17

class B {
  private static int x1;
  public void setX(int x) {x1 = x;}
  public int getX() {return x1;}
  public static void main(String[] args) {
    int i1 = 0, j1 = 0;
    do {
      System.out.print(j1++);
      assert (i1 = j1 + x1) < 6;
    } while (i1 < 3);
}}

Assuming that the setX method is never invoked, which statements are true?

Question 18

class GFM12 {
  static int x;                             // 1
  public static void main(String[] args) {  // 2
    int y;                                  // 3
    System.out.println("x="+x);             // 4
    System.out.println("y="+y);             // 5
}}

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

Question 19

class EBH002 {
  static int m(int i) {
    System.out.print(i + ", ");
    return i;
  }
  public static void main(String s[]) {
    m(m(1) + m(2) % m(3) * m(4));
}}

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

Question 20

class Primitives {
  static void printFloat(float f) {System.out.println(f);}
  static void printDouble(double d) {System.out.println(d);}
  public static void main(String[] args) {
    byte b = 1;     // 1
    short s = b;    // 2
    char c = s;     // 3
    int i = c;      // 4
    long l = i;     // 5
    float f = l;    // 6
    printFloat(i);  // 7
    printFloat(l);  // 8
    printDouble(l); // 9
}}

A compile-time error is generated at which line?

Question 21

interface I1 {}
interface I2 {}
class Base implements I1 {}
class Sub extends Base implements I2 {}
class Orange {
  public static void main(String args[]) {
    Base base = new Base();
    I1 i1 = base;           // 1
    Sub sub = (Sub)base;    // 2
}}

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

Question 22

class Purple {
  public static void main (String []args) {
    int[] i = {1,2,3};  // 1
    Object obj = i;     // 2
    i = obj;            // 3
}}

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

Question 23

class GFC216 {
  static String m(float i) {return "float";}
  static String m(double i) {return "double";}
  public static void main (String[] args) {
    char a1 = 1; long b1 = 2;
    System.out.print(m(a1)+","+ m(b1));
}}

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

Question 24

class C {
  void printS1() {System.out.print("C.printS1 ");}
  static void printS2() {System.out.print("C.printS2 ");}
}
class D extends C {
  void printS1(){System.out.print("D.printS1 ");}
  void printS2() {System.out.print("D.printS2 ");}
  public static void main (String args[]) {
    C c = new D(); c.printS1(); c.printS2();
}}

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

Question 25

class B {
  private static String s1 = "s1";
  final String s2 = "s2";
  B () {new Z("s5","s6");}
  static class Z {
    final String s3 = "s3";
    static String s4 = "s4";
    Z (final String s5, String s6) {
      System.out.print(???);
  }}
  public static void main(String args[]) {new B();}
}

Which variable can not be substituted for ??? without causing a compile-time error?

Question 26

Which of these words belong to the set of Java keywords?

Question 27

class EBH102 {
  static int m(int i) {
    System.out.print(i + ",");
    return i;
  }
  public static void main(String s[]) {
    int i = 1;
    int j = m(i++) + m(i++) * m(i++) + m(i++);
    System.out.print(j % 5);
}}

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

Question 28

class GFC303 {
  private String name;
  public GFC303(String name) {this.name = name;}
  public void setName(String name) {this.name = name;}
  public String getName() {return name;}
  public static void m1(GFC303 pet1, GFC303 pet2) {
    pet1 = new GFC303("Fish");
    pet2 = null;
  }
  public static void main (String[] args) {
    GFC303 pet1 = new GFC303("Dog");
    GFC303 pet2 = new GFC303("Cat");
    m1(pet1,pet2);
    System.out.println(pet1.getName() + "," + pet2.getName());
}}

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

Question 29

class I {
  private String name;
  public String name() {return name;}
  public I(String s) {name = s;}
}
class J {
  public static void m1(I i) {i = null;}
  public static void main (String[] args) {
    I i = new I("X");           // 1
    m1(i);                      // 2
    System.out.print(i.name()); // 3
}}

Which of the following is a true statement?