Output of Java programs | Set 29

Question 1. What is the output of the following question? JAVA

class Test1 {
public
    static void main(String[] args)
    {
        int String = 65;
        int Runnable = 97;

        System.out.print(String + " : " + Runnable);
    }
}

Option A) Error B) A : a C) 65 : 97 D) None

Output: C

Explanation : We can use all predefined Java class name and interface name as identifiers. Question 2. What is the output of the following question? JAVA

class Test2 {
public
    static void main(String[] args)
    {
        int if = 65;
        int else = 97;

        System.out.println(if + " : " + else);
    }
}

Option A) Error B) A : B C) 65 : 97 D) None

Output: A

Explanation : We can't use reserved words as identifiers. Question 3. What is the output of the following question? JAVA

class Test3 {
public
    static void main(String[] args)
    {
        int x = 1;

        if (x) {
            System.out.print("GeeksForGeeks");
        } else {
            System.out.print("GFG");
        }
    }
}

Option A) GeeksForGeeks B) GFG C) Error D) None

Output: C

Explanation :In Java, Compiler gives error - Incompatible types : int can not be converted to boolean type. But in C or C++ its a valid statement. Question 4. What is the output of the following question? JAVA

class Test4 {
public
    static void main(String[] args)
    {
        double d1 = 123.456;
        double d2 = 12_3.4_5_6;
        double d3 = 12_3.4_56;

        System.out.println(d1);
        System.out.println(d2);
        System.out.println(d3);
    }
}

Option A) Error B) 123.456 12_3.4_5_6 12_3.4_56 C) 123.456 123.456 123.456 D) None

Output: C

Explanation : From (1.7v onwards)we can use '_'(under Score) Symbol between digits of numeric literals. See more at Java naming conventions. Question 5. What is the output of the following question? JAVA

class Test5 {
public
    static void main(String[] args)
    {
        double d1 = _123 .456;
        double d2 = 12_3_.4_5_6;
        double d3 = 12_3.4_56_;

        System.out.println(d1);
        System.out.println(d2);
        System.out.println(d3);
    }
}

Option A) Error B) 123.456 12_3.4_5_6 12_3.4_56 C) 123.456 123.456 123.456 D) None

Output: A

Explanation : We can use the '_' (under score) symbol only between the digits. if we are using anywhere else we will get compile time error - Illegal under score.