Java Program to Convert a Float value to String

Given a Float value in Java, the task is to write a Java program to convert this float value to string type.

Examples: 

Input: 1.0
Output: "1.0"

Input: 3.14
Output: "3.14"

Strings - Strings in Java are objects that are supported internally by a char array. Since arrays are immutable, and strings are also a type of exceptional array that holds characters, therefore, strings are immutable as well. 

Float - The float data type is a single-precision 32-bit IEEE 754 floating-point. Its value range is unlimited. Using a float (instead of double) is suggested if you need to save memory in large arrays of floating-point numbers. Its default value is 0.0F.

Approaches

There are numerous approaches to convert a float value to a String in Java. These are - 

• Using + operator
• Using String.valueOf() method
• Using Float.toString() method

Approach 1 - Using + operator 

One method is to create a string variable and then append the float value to the string variable. This will directly convert the float value to a string and add it to the string variable. 

Below is the implementation of the above approach:

// Java Program to convert float value to String value
class GFG {

    // Function to convert float value to String value
    public static String convertFloatToString(float floatValue)
    {
        // Convert float value to String value
        // using + operator method
        String stringValue = "" + floatValue;

        return (stringValue);
    }

    // Driver code
    public static void main(String[] args)
    {

        // The float value
        float floatValue = 1f;

        // The expected string value
        String stringValue;

        // Convert float to string
        stringValue = convertFloatToString(floatValue);

        // Print the expected string value
        System.out.println(
            floatValue + " after converting into string = "
            + stringValue);
    }
}

1.0 after converting into string = 1.0

Time Complexity: O(1)
Auxiliary Space: O(1)

Approach 2 - Using String.valueOf() method 

The simplest way to do so is using the valueOf() method of the String class in java.lang package. This method takes the float value to be parsed and returns the value in String type from it. 

Syntax: 

String.valueOf(floatValue);

Below is the implementation of the above approach:

// Java Program to convert float value to String value
class GFG {

    // Function to convert float value to String value
    public static String
    convertFloatToString(float floatValue)
    {
        // Convert float value to String value
        // using valueOf() method
        return String.valueOf(floatValue);
    }

    // Driver code
    public static void main(String[] args)
    {

        // The float value
        float floatValue = 1;

        // The expected string value
        String stringValue;

        // Convert float to string
        stringValue = convertFloatToString(floatValue);

        // Print the expected string value
        System.out.println(
            floatValue
            + " after converting into string = "
            + stringValue);
    }
}

1.0 after converting into string = 1.0

Time Complexity: O(1)
Auxiliary Space: O(1)

Approach 3 - Using Float.toString() method 

The Float.toString() method can also be used to convert the float value to a String. The toString() is the static method of the Float class.

Syntax:

String str = Float.toString(val);

Below is the implementation of the above approach:

// Java Program to convert float value to String value
import java.util.*;
class GFG {

    // Function to convert float value to String value
    public static String
    convertFloatToString(float floatValue)
    {
        // Convert float value to String value
        // using valueOf() method
        return Float.toString(floatValue);
    }

    // Driver code
    public static void main(String[] args)
    {

        // The float value
        float floatValue = 1;

        // The expected string value
        String stringValue;

        // Convert float to string
        stringValue = convertFloatToString(floatValue);

        // Print the expected string value
        System.out.println(
            floatValue
            + " after converting into string = "
            + stringValue);
    }
}

1.0 after converting into string = 1.0

Time Complexity: O(1)
Auxiliary Space: O(1)