Constructor toString() method in Java with Examples

Last Updated : 29 Oct, 2019

The toString() method of java.lang.reflect.Constructor class is used to return string representation of this Constructor.This string is the collection of all the properties of this constructor. For creating this string method adds access modifiers of the constructor with the name of the declaring class of constructor then add parenthesized and add a comma-separated list of the constructor’s formal parameter types together.

Syntax:

public String toString()

Parameters: This method accepts nothing.

Return: This method returns string describing this Constructor.

Below programs illustrate toString() method:
Program 1:

// Java program to illustrate toString() method 
  
import java.lang.annotation.Annotation; 
import java.lang.reflect.Constructor; 
  
public class GFG { 
  
    public static void main(String[] args) 
    { 
        // create a class object 
        Class classObj = shape.class; 
  
        // get Constructor object 
        // array from class object 
        Constructor[] cons = classObj.getConstructors(); 
  
        // check get string representation 
        String str = cons[0].toString(); 
  
        // print result 
        System.out.println("Constructor : " + str); 
    } 
  
    public class shape { 
  
        public shape(Object... objects) 
        { 
        } 
    } 
} 

Output:

Constructor : public GFG$shape(GFG, java.lang.Object[])

Program 2:

// Java program to illustrate toString() method 
  
import java.lang.annotation.Annotation; 
import java.lang.reflect.Constructor; 
  
public class GFG { 
  
    public static void main(String[] args) 
    { 
        // create a class object 
        Class classObj = String.class; 
  
        // get Constructor object 
        // array from class object 
        Constructor[] cons = classObj.getConstructors(); 
  
        for (int i = 0; i < cons.length; i++) { 
  
            String str = cons[i].toString(); 
  
            // print result 
            System.out.println(str); 
        } 
    } 
} 

Output:

public java.lang.String(byte[], int, int)
public java.lang.String(byte[], java.nio.charset.Charset)
public java.lang.String(byte[], java.lang.String) throws java.io.UnsupportedEncodingException
public java.lang.String(byte[], int, int, java.nio.charset.Charset)
public java.lang.String(byte[], int, int, java.lang.String) throws java.io.UnsupportedEncodingException
public java.lang.String(java.lang.StringBuilder)
public java.lang.String(java.lang.StringBuffer)
public java.lang.String(byte[])
public java.lang.String(int[], int, int)
public java.lang.String()
public java.lang.String(char[])
public java.lang.String(java.lang.String)
public java.lang.String(char[], int, int)
public java.lang.String(byte[], int)
public java.lang.String(byte[], int, int, int)

References: https://docs.oracle.com/javase/10/docs/api/java/lang/reflect/Constructor.html#toString()