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SCJP 1.4 Mock Exam – 4

Mock Exam – 4
Q1 public class Test1{

static void method(Object obj){

System.out.println(“Object”);

}

static void method(String str){

System.out.println(“String”);

}

public static void main(String args[]){

method(null);

}

}

What will be the output? 
A1 String
A2 Object
A3 null
A4 Compiler Error
Q2 public class Test2{

static void method(StringBuffer obj){

System.out.println(“StringBuffer”);

}

static void method(String str){

System.out.println(“String”);

}

public static void main(String args[]){

method(null);

}

}

What will be the output? 
A1 String
A2 Object
A3 null
A4 Compiler Error
Q3 class Test{}

public class Test3{

static void method(Object obj){

System.out.println(“StringBuffer”);

}

static void method(String str){

System.out.println(“String”);

}

static void method(Test t){

System.out.println(“Test”);

}

public static void main(String args[]){

method(null);

}

}

What will be the output?
A1 String
A2 Object
A3 Test
A4 Compiler Error
Q4 public class Test4{

public static void main(String args[]){

I i1 = new A();

I i2 = new B();

A a = new A();

System.out.println(i1
instanceof I);

System.out.println(i2
instanceof B);

System.out.println(a
instanceof I);

}

}

interface I{}

class A implements I{}

class B implements I{}

What will be the output?
A1 true true true
A2 true false true
A3 true false false
A4 Compiler Error
Q5 public class Test5{

public static void main(String args[]){

System.out.println(I.k);

}

}

interface I{

int k;

}

What will be the output?
A1 true true true
A2 true false true
A3 true false false
A4 Compiler Error
Q6 public class Test6 implements I{

int k = 1;

public static void main(String args[]){

System.out.println(k);

}

}

interface I{

int k = 0;

}

What will be the output?
A1 0
A2 1
A3 null
A4 Compiler Error
Q7 public class Test7 implements I{

int k = 1;

static{

k = k * 2;

}

{

k = k * 2;

}

public static void main(String args[]){

Test7 t1 = new
Test7();

Test7 t2 = new
Test7();

System.out.println(t1.k);

System.out.println(t2.k);

System.out.println(k);

}

}

What will be the output?
A1 0
A2 1
A3 null
A4 Compiler Error
Q8 public class Test8{

static int k = 1;

static{

k = k * 2;

}

{

k = k * 2;

}

public static void main(String args[]){

System.out.println(k);

}

}

What will be the output?
A1 1
A2 2
A3 4
A4 Compiler Error
Q9 public class Test9{

static int k = 1;    {

k = k * 2;

}

public static void main(String
args[]){

System.out.println(k);

}

}

What will be the output?

 
A1 1
A2 2
A3 4
A4 Compiler Error
Q10 public class Test10{

final static int k;

static{

k = 0;

}

public static void main(String
args[]){

System.out.println(k);

}

}

What will be the output?
A1 0
A2 1
A3 null
A4 Compiler Error
Answers
1 String
2 Compiler Error
3 Compiler Error
4 true true true
5 true true true
6 Compiler Error
7 Compiler Error
8 2
9 1
10 0