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1. A method name min() that needs two integer arguments is declared as

Public void min();

Public void min (int a, b);

Public void min (int a, int b);

Public int min (a, b);

SKIP THE QUESTION

The correct answer is "public void min (int a, int b)" because it declares a method named "min" that takes two integer arguments, "a" and "b". The "public" keyword indicates that the method can be accessed from other classes. The "void" keyword means that the method does not return any value. The method is correctly declared with the correct parameter types for two integers.

Explanation

The correct answer is "public void min (int a, int b)" because it declares a method named "min" that takes two integer arguments, "a" and "b". The "public" keyword indicates that the method can be accessed from other classes. The "void" keyword means that the method does not return any value. The method is correctly declared with the correct parameter types for two integers.

2. You store java source code files with following extension?

.java

.class

.src

.javadoc

SKIP THE QUESTION

The correct answer is ".java" because Java source code files are typically saved with this extension. This allows the Java compiler to recognize and process the file as a valid Java source code file. The other options, such as ".class", ".src", and ".javadoc", are not used to store Java source code files. ".class" files are generated by the Java compiler after successfully compiling the source code, while ".src" and ".javadoc" are not standard file extensions for Java source code files.

Explanation

The correct answer is ".java" because Java source code files are typically saved with this extension. This allows the Java compiler to recognize and process the file as a valid Java source code file. The other options, such as ".class", ".src", and ".javadoc", are not used to store Java source code files. ".class" files are generated by the Java compiler after successfully compiling the source code, while ".src" and ".javadoc" are not standard file extensions for Java source code files.

3. In Java language, the argument to the method is within

Curly braces

Parenthesis

Square brackets

Single quote

SKIP THE QUESTION

In Java language, the argument to the method is enclosed within parentheses. Parentheses are used to define and separate the arguments that are passed to a method. This is a fundamental syntax rule in Java and is necessary for the proper execution of methods.

Explanation

In Java language, the argument to the method is enclosed within parentheses. Parentheses are used to define and separate the arguments that are passed to a method. This is a fundamental syntax rule in Java and is necessary for the proper execution of methods.

4. State which of the following statements are true
(1) A series of characters that appear in double quote is a Char literal
(2) Java language is case sensitive
(3) The Java programming language is both compiled and interpreted.
(4) As long as a computer has a Java Virtual Machine, the same program written in the Java programming language can run on any computer

All four

2,3 and 4

2 and 4

2 and 3

SKIP THE QUESTION

The given answer states that statements 2, 3, and 4 are true. Statement 2 is true because Java is a case-sensitive language, meaning that uppercase and lowercase letters are considered different. Statement 3 is true because Java is both compiled and interpreted. It is compiled into bytecode and then interpreted by the Java Virtual Machine. Statement 4 is true because Java programs can run on any computer that has a Java Virtual Machine installed, regardless of the underlying hardware or operating system.

Explanation

The given answer states that statements 2, 3, and 4 are true. Statement 2 is true because Java is a case-sensitive language, meaning that uppercase and lowercase letters are considered different. Statement 3 is true because Java is both compiled and interpreted. It is compiled into bytecode and then interpreted by the Java Virtual Machine. Statement 4 is true because Java programs can run on any computer that has a Java Virtual Machine installed, regardless of the underlying hardware or operating system.

5. Java language has support for which following types of comments

Block, line and javadoc

Javadoc, literal and string

Javadoc, char and string

Single, multiple and quote

SKIP THE QUESTION

Java language supports three types of comments: block, line, and javadoc. Block comments are enclosed between /* and */, and can span multiple lines. Line comments start with // and only cover a single line. Javadoc comments are used to generate documentation and are enclosed between /** and */. They can also span multiple lines.

Explanation

Java language supports three types of comments: block, line, and javadoc. Block comments are enclosed between /* and */, and can span multiple lines. Line comments start with // and only cover a single line. Javadoc comments are used to generate documentation and are enclosed between /** and */. They can also span multiple lines.

6. A subclass is also called as

Inner class

Nested class

Derived class

Hidden class

SKIP THE QUESTION

A subclass is also known as a derived class. In object-oriented programming, a subclass is a class that inherits properties and behaviors from a parent class (also known as a superclass). The subclass can add additional features or modify the inherited ones. Therefore, derived class is the correct term to describe a subclass.

Explanation

A subclass is also known as a derived class. In object-oriented programming, a subclass is a class that inherits properties and behaviors from a parent class (also known as a superclass). The subclass can add additional features or modify the inherited ones. Therefore, derived class is the correct term to describe a subclass.

7. State which of the following statements are True
(1) Each method in a parent class can be overridden at most once in any one subclass
(2) A method can be overloaded in the class it is defined as well as in the subclass of its class
(3) Overriding methods must return exactly the same type as the method they override
(4) An overriding method must not be less accessible than the method it
overrides

All 4

1 and 2

1,2 and 4

SKIP THE QUESTION

All 4 statements are true.

(1) Each method in a parent class can be overridden at most once in any one subclass, meaning that a subclass can override a method from its parent class only once.

(2) A method can be overloaded in the class it is defined as well as in the subclass of its class, meaning that a method can have multiple versions with different parameters within the same class or in its subclasses.

(3) Overriding methods must return exactly the same type as the method they override, meaning that the return type of the overriding method must be the same as the return type of the method it is overriding.

(4) An overriding method must not be less accessible than the method it overrides, meaning that the access modifier of the overriding method should be the same or more accessible than the method it is overriding.

Explanation

All 4 statements are true.

(1) Each method in a parent class can be overridden at most once in any one subclass, meaning that a subclass can override a method from its parent class only once.

(2) A method can be overloaded in the class it is defined as well as in the subclass of its class, meaning that a method can have multiple versions with different parameters within the same class or in its subclasses.

(3) Overriding methods must return exactly the same type as the method they override, meaning that the return type of the overriding method must be the same as the return type of the method it is overriding.

(4) An overriding method must not be less accessible than the method it overrides, meaning that the access modifier of the overriding method should be the same or more accessible than the method it is overriding.

8. What will be the outcome of executing following code.
class MyClass
{
public static void main (String args[])
{
   String s1[] = new String[5];
   String str = s1[0].toUpperCase();
   System.out.println(str);
}
}

Will print null

Will give NullPointerException

Will not compile

Will print NULL

SKIP THE QUESTION

The code initializes an array of Strings, but it does not assign any values to the elements of the array. Therefore, when the code tries to access the first element of the array (s1[0]) and call the toUpperCase() method on it, a NullPointerException will occur because the element is null. This will result in a runtime error and the program will terminate.

Explanation

The code initializes an array of Strings, but it does not assign any values to the elements of the array. Therefore, when the code tries to access the first element of the array (s1[0]) and call the toUpperCase() method on it, a NullPointerException will occur because the element is null. This will result in a runtime error and the program will terminate.

9. State which of the following statements are True
(1) Java language support multi-dimentional arrays
(2) StringBuffer class is alternative to String class
(3) A class which you create only to extend from, but not to instantiate
from is called derived class
(4) You cannot instantiate objects of interfaces or abstract classes

All 4

1 and 2

1,2 and 4

SKIP THE QUESTION

The given answer states that statements 1, 2, and 4 are true.

Statement 1 is true because Java language does support multi-dimensional arrays.

Statement 2 is true because the StringBuffer class in Java is an alternative to the String class. It provides mutable strings and additional methods for string manipulation.

Statement 4 is true because interfaces and abstract classes cannot be instantiated directly. They can only be implemented by classes or extended by other classes.

Therefore, the correct answer is 1, 2, and 4.

Explanation

The given answer states that statements 1, 2, and 4 are true.

Statement 1 is true because Java language does support multi-dimensional arrays.

Statement 2 is true because the StringBuffer class in Java is an alternative to the String class. It provides mutable strings and additional methods for string manipulation.

Statement 4 is true because interfaces and abstract classes cannot be instantiated directly. They can only be implemented by classes or extended by other classes.

Therefore, the correct answer is 1, 2, and 4.

10. What will be the outcome of executing following code.
class MyClass
{
public static void main(String []args)
{
   final int i = 100;
   byte b = i;
   System.out.println(b);
}
}

Will give compilation error

Will compile and print 100

Will throw an exception

SKIP THE QUESTION

The code will compile and print 100 because the variable "i" is declared as final, which means its value cannot be changed. When the value of "i" is assigned to the byte variable "b", it will be automatically converted to a byte value. Since the value of "i" (100) can be represented as a byte, there will be no compilation error and the value 100 will be printed.

Explanation

The code will compile and print 100 because the variable "i" is declared as final, which means its value cannot be changed. When the value of "i" is assigned to the byte variable "b", it will be automatically converted to a byte value. Since the value of "i" (100) can be represented as a byte, there will be no compilation error and the value 100 will be printed.

11. What will be the outcome of executing following code.
class MyClass
{
public static void main(String []args)
{
   int i = 100;
   byte b = i;
   System.out.println(b);
}
}

Will give compilation error

Will compile and print 100

Will throw an exception

SKIP THE QUESTION

The code will give a compilation error because a byte cannot directly hold the value of an integer without explicit casting. In this code, the variable "i" is of type integer and the variable "b" is of type byte. When the value of "i" is assigned to "b", there is a type mismatch because the range of a byte is smaller than the range of an integer. Therefore, the code will not compile.

Explanation

The code will give a compilation error because a byte cannot directly hold the value of an integer without explicit casting. In this code, the variable "i" is of type integer and the variable "b" is of type byte. When the value of "i" is assigned to "b", there is a type mismatch because the range of a byte is smaller than the range of an integer. Therefore, the code will not compile.

12. Which are the valid declarations for an integer literal
(1) 0
(2) -5
(3) 0416
(4) 0xabcdef

All 4

1 and 2

1,2 and 3

SKIP THE QUESTION

All 4 options are valid declarations for an integer literal. Option 1 represents the decimal number 0, option 2 represents the negative decimal number -5, option 3 represents the octal number 0416, and option 4 represents the hexadecimal number 0xabcdef.

Explanation

All 4 options are valid declarations for an integer literal. Option 1 represents the decimal number 0, option 2 represents the negative decimal number -5, option 3 represents the octal number 0416, and option 4 represents the hexadecimal number 0xabcdef.

13. What will be the result of compiling following code

public class MyClass
{
public static void main(String args[])
{
System.out.println("In first main()");
}
public static void main(char args[])
{
System.out.println('a');
}
}

(1) Code will not compile and will give "Duplicate main() method declaration" error

(2) Code will compile correctly but will give a runtime exception

(3) Code will compile correctly and will print "In first main()" (without quotes) when run with argument of 'a'.

(4) Code will compile correctly and will print "a" (without quotes) when run with argument of 'a'.

SKIP THE QUESTION

The code will compile correctly because it defines two main() methods with different parameter types. When the code is run with the argument of 'a', it will execute the main() method that accepts a char array as an argument. However, since the argument is a single character 'a', it will not match the char array parameter. Therefore, the code will not print anything.

Explanation

The code will compile correctly because it defines two main() methods with different parameter types. When the code is run with the argument of 'a', it will execute the main() method that accepts a char array as an argument. However, since the argument is a single character 'a', it will not match the char array parameter. Therefore, the code will not print anything.