Step by Step solution about How to resolve the algorithm Interactive programming (repl) step by step in the Java programming language

This Java code demonstrates string concatenation and its usage through a REPL (Read-Evaluate-Print-Loop) console called jshell. A step-by-step explanation of the code:

1. Main Method:

   • The main method is the entry point of the program:
     • System.out.println(concat("Rosetta", "Code", ":"));:
       • Calls the concat method with the strings "Rosetta," "Code," and ":" and prints the result.

2. concat Method:

   • It's a static method that takes three string arguments: a, b, and c.
   • It concatenates the strings in the order a + c + c + b and returns the result.

3. JShell:

   • The code includes a sample jshell session to demonstrate the usage of the concat method interactively.
   • concat("Rosetta", "Code", ":"):
     • Evaluates the concat method with the given arguments.
   • The result, "Rosetta::Code," is printed to the console.

public static void main(String[] args) {
    System.out.println(concat("Rosetta", "Code", ":"));
}

public static String concat(String a, String b, String c) {
   return a + c + c + b;
}

Rosetta::Code


Java has an interactive REPL (Read-Evaluate-Print-Loop) console, jshell, that is included with the JDK. 
The REPL is started by invoking: $JAVA_HOME/bin/jshell 
Here is a sample session to accomplish the task.
 
 | Welcome to JShell -- Version 20
 | For an introduction type: /help 

 jshell> String concat(String a, String b, String c) { return a + c + c + b; }
 |  created method concat(String, String, String)
   
 jshell> concat("Rosetta", "Code", ":")
 $2 ==> "Rosetta::Code"
  
 jshell>