Integer toString() in Java

  1. The java.lang.Integer.toString() is an inbuilt method in Java which is used to return the String object representing this Integer’s value.

    Syntax :

    public static String toString()

    Parameters: The method does not accept any parameters.

    Return Value:The method returns the string object of the particular Integer value.



    Below program illustrates the Java.lang.Integer.toString() method:

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    // Java program to illustrate the
    // toString() Method
    import java.lang.*;
      
    public class Geeks{
      
    public static void main(String[] args) {
      
        Integer obj = new Integer(8);
          
        //It will return a string representation     
        String stringvalue1 = obj.toString();
        System.out.println("String Value= "
                                stringvalue1);
          
          
            Integer obj3 = new Integer(10);
          
        //It will return a string representation 
        String stringvalue3 = obj3.toString();
        System.out.println("String Value = "
                                stringvalue3);
          
    }
    }

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    Output:

    String Value= 8
    String Value = 10
    
  2. The java.lang.Integer.toString(int a) is an inbuilt method in Java which is used to return a String object, representing the specified integer in the parameter.
    Syntax :

    public static String toString(int a)

    Parameters: The method accepts one parameter a of integer type and refers to the integer needed to be converted to string.

    Return Value: The method returns the string representation of the argument in a particular base.

    Examples:

    For base 8: 
    Input: int a = 75 
    Output: "75"
    
    For base 10:
    Input: int a = -787 
    Output: "-787"
    

    Below programs illustrate the Java.lang.Integer.toString(int a) method:
    Program 1:

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    // Java program to illustrate the
    // toString(int a) method
    import java.lang.*;
      
    public class Geeks{
      
    public static void main(String[] args) {
      
        Integer obj = new Integer(8);
          
        // It will return a string representation
            // in base 8
        String stringvalue1 = obj.toString(75);
        System.out.println("String Value = "
                                stringvalue1);
          
        Integer obj2 = new Integer(8);
          
        // It will return a string representation
            // in base 2
        String stringvalue2 = obj2.toString(6787);
        System.out.println("String Value = "
                                stringvalue2);
          
          
            Integer obj3 = new Integer(10);
          
        // It will return a string representation 
            // in base 10
        String stringvalue3 = obj3.toString(-787);
        System.out.println("String Value = "
                                stringvalue3);
          
    }

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    Output:

    String Value = 75
    String Value = 6787
    String Value = -787
    

    Program 2: For decimal and string parameters.
    Note: This results in an error and as well for the absence of suitable Integer constructor.

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    // Java program to illustrate the
    // Java.lang.Integer.toString(int a)method
    import java.lang.*;
    public class Geeks{
      
    public static void main(String[] args) {
        Integer obj = new Integer(8);    
        String stringvalue1 = obj.toString(58.5);
        System.out.println("String Value = "
                                stringvalue1);
          
        Integer obj2 = new Integer(8);    
        String stringvalue2 = obj2.toString("317");
        System.out.println("String Value = "
                                stringvalue2);
          
          
        // Empty constructor will result in an error
        Integer obj3 = new Integer();
        String stringvalue3 = obj3.toString(-787);
        System.out.println("String Value = "
                                stringvalue3);
          
    }

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    Output:


    prog.java:8: error: incompatible types: possible 
    lossy conversion from double to int
        String stringvalue1 = obj.toString(58.5);
                                           ^
    prog.java:12: error: incompatible types: String cannot 
    be converted to int
        String stringvalue2 = obj2.toString("317");
                                            ^
    prog.java:17: error: no suitable constructor found for 
    Integer(no arguments)
        Integer obj3 = new Integer();
                       ^
        constructor Integer.Integer(int) is not applicable
          (actual and formal argument lists differ in length)
        constructor Integer.Integer(String) is not applicable
          (actual and formal argument lists differ in length)
    Note: Some messages have been simplified; recompile with 
    -Xdiags:verbose to get full output
    3 errors
  3. The java.lang.Integer.toString(int a, int base) is an inbuilt method in Java which is used to return a string representation of the argument a in the base, specified by the second argument base. If the radix/base is smaller than Character.MIN_RADIX or larger than Character.MAX_RADIX, then the base 10 is used. The ASCII characters which are used as digits: 0 to 9 and a to z.
    Syntax:

    public static String toString(int a, int base)

    Parameter: The method accepts two parameters:

    • a: This is of integer type and refers to the integer value that is to be converted.
    • base: This is also of integer type and refers to the base that is to be used while representing the strings.

    Return Value: The method returns a string representation of the specified argument in the specified base.

    Examples:

    Input: a = 71, base = 2
    Output: 1000111
    
    Input: a = 314, base = 16
    Output: 13a
    

    Below programs illustrate the Java.lang.Integer.toString(int a, int base) Method:
    Program 1:

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    // Java program to illustrate the
    // toString(int, int) Method
    import java.lang.*;
      
    public class Geeks{
      
    public static void main(String[] args) {
      
            Integer a = new Integer(10);
          
        // It returns a string representation 
            // in base 2
        String returnvalue = a.toString(5254, 2);
        System.out.println("String Value = "
                                returnvalue);
      
        // It returns a string representation 
            // in base 8
        returnvalue = a.toString(35, 8);
        System.out.println("String Value = "
                                returnvalue);
      
        // It returns a string representation 
            // in base 16
        returnvalue = a.toString(47, 16);
        System.out.println("String Value = "
                                returnvalue);
      
        // It returns a string representation 
            // in base 10
        returnvalue = a.toString(451, 10);
        System.out.println("String Value = "
                                returnvalue);
    }

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    Output:

    String Value = 1010010000110
    String Value = 43
    String Value = 2f
    String Value = 451
    

    Program 2:

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    // Java program to illustrate the
    // toString(int, int) Method
    import java.lang.*;
      
    public class Geeks{
      
    public static void main(String[] args) {
      
            Integer a = new Integer(10);
          
        // It returns a string representation 
            // in base 2
        String returnvalue = a.toString(-525, 2);
        System.out.println("String Value = "
                                returnvalue);
      
        // It returns a string representation 
            // in base 8
        returnvalue = a.toString(31, 8);
        System.out.println("String Value = "
                                returnvalue);
      
        // It returns a string representation 
            // in base 16
        returnvalue = a.toString(28, 16);
        System.out.println("String Value = "
                                returnvalue);
      
        // It returns a string representation 
            // in base 10
        returnvalue = a.toString(29, 10);
        System.out.println("String Value = "
                                returnvalue);
    }

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    Output:

    String Value = -1000001101
    String Value = 37
    String Value = 1c
    String Value = 29
    


    My Personal Notes arrow_drop_up

    lets make it a lil simple

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