Integer toString() in Java (original) (raw)

Last Updated : 05 Dec, 2018

  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: java `
    // 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);

}
}
**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:** java
// 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);

}
}
**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. java
// 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);

}
}
` 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: 

// 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);

}
}
**Output:** String Value = 1010010000110 String Value = 43 String Value = 2f String Value = 451 **Program 2:** java
// 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);

}
}
`
Output:
String Value = -1000001101
String Value = 37
String Value = 1c
String Value = 29