Output of Java Programs | Set 21 (Type Conversions)

Prerequisite – Type Conversions in Java with Examples

1) What is the output of the following program?

public class Test
{
    public static void main(String[] args)
    {
        int value = 554;
        String var = (String)value;  //line 1
        String temp = "123";
        int data = (int)temp; //line 2
        System.out.println(data + var);
    }
}

a) 677
b) Compilation error due to line 1
c) Compilation error due to line 2
d) Compilation error due to line 1 and line 2

Ans. (d)
Explanation: Converting from int to String as well as converting from String to int is not allowed in java.

2) What is the output of the following program?

public class Test
{
    public static void main(String[] args)
    {
        double data = 444.324;
        int value = data;
        System.out.println(data);
    }
}

a) 444.324
b) 444
c) Runtime error
d) Compilation error

Ans. (d)
Explanation: Converting from a bigger data type to a smaller data type is not allowed in java as it is a lossy conversion.

3) What is the output of the following program?

public class Test
{
    public static void main(String[] args)
    {
        double data = 444.324;
        int sum = 9;
        float value = 5.1f;
        System.out.println(data + sum + value);

    }
}

a) 444.32495.1
b) 456
c) 458.42399
d) 458.4

Ans. (c)
Explanation: If one of the operands is long, double or float, the entire expression is converted to long, double or float respectively.

4) What is the output of the following program?

public class Test
{
    public static void main(String[] args)
    {
        byte var = 1;
        var = (byte) var * 0; //line 1
        byte data = (byte) (var * 0); //line 2
        System.out.println(var);
    }
}

a) 0
b) Compilation error due to line 1
c) Compilation error due to line 2
d) Compilation error due to line 1 and line 2

Ans. (b)
Explanation: When the expressions are evaluated, the data type of the result is implicitly changed to a larger data type and therefore, explicit recasting has to be done as shown in line 2. On the other hand, line 1 shows compilation error because the expression on the right side has data type as int whereas left side it is byte.

5) What is the output of the following program?

public class Test
{
    public static void main(String[] args)
    {
        System.out.println((100/25.0)*Integer.parseInt("5") + 50);
    }
}

a) Compilation error
b) 70
c) 70.0
d) Runtime error

Ans. (c)
Explanation: If a double value is used in an expression then the output is returned in double format rather than an int.

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