Java String Exercises: Get the canonical representation of the string object

Java String: Exercise-20 with Solution

Write a Java program to get the canonical representation of the string object.

Sample Solution:

Java Code:

public class Exercise20 {
public static void main(String[] args)
        // Create three strings in three different ways.
        String str1 = "Java Exercises";
        String str2 = new StringBuffer("Java").append(" Exercises").toString();
        String str3 = str2.intern();

        // Determine which strings are equivalent using the ==
        // operator (as compared to calling equals(), which is
        // a more expensive operation.
        System.out.println("str1 == str2? " + (str1 == str2));
        System.out.println("str1 == str3? " + (str1 == str3));

Sample Output:

str1 == str2? false                                                                                           
str1 == str3? true


Flowchart: Java String  Exercises -  Get the canonical representation of the string object

Visualize Java code execution (Python Tutor):

Java Code Editor:

Improve this sample solution and post your code through Disqus

Previous: Write a Java program to get the index of all the characters of the alphabet.
Next: Write a Java program to get the last index of a string within a string.

What is the difficulty level of this exercise?

Java: Tips of the Day

Array vs ArrayLists:

The main difference between these two is that an Array is of fixed size so once you have created an Array you cannot change it but the ArrayList is not of fixed size. You can create instances of ArrayLists without specifying its size. So if you create such instances of an ArrayList without specifying its size Java will create an instance of an ArrayList of default size.

Once an ArrayList is full it re-sizes itself. In fact, an ArrayList is internally supported by an array. So when an ArrayList is resized it will slow down its performance a bit as the contents of the old Array must be copied to a new Array.

At the same time, it's compulsory to specify the size of an Array directly or indirectly while creating it. And also Arrays can store both primitives and objects while ArrayLists only can store objects.

Ref: https://bit.ly/3o8L2KH