Java Program to Add Package Statement to Multiple Java Source Files

How can a Java program be used to add package statements to multiple Java source files?

Suppose you have Java source files distributed across different directories named chapter1, chapter2, ..., chapter34. How can you write a program to automatically insert the necessary package statement for each file?

Java Program for Adding Package Statements

A Java program is required that adds a package declaration to the top of every Java source file in a specified directory hierarchy. The program should traverse the directory tree, find all \'.java\' files, then prepend the necessary package statement.

The student is tasked to write a program to add a package declaration line at the top of every Java source file under directories named chapter1, chapter2,...,chapter34. You should use Java I/O and nio packages for this task.

Here is a basic skeleton program that you can build upon:

import java.io.*;

import java.nio.file.*;

public class Exercise12_18 {

public static void main(String[] args) throws Exception {

if (args.length != 1) {

System.out.println('Enter the root directory');

System.exit(1);

}

Path pathStart = Paths.get(args[0]);

Files.walk(pathStart)

.filter(path -> path.toString().endsWith('.java'))

.forEach(path -> addPackageStatement(path));

}

static void addPackageStatement(Path javaFile) {

// Memory for lines of the java file

StringBuilder fileContent = new StringBuilder();

// Add package statement

fileContent.append('package ').append(javaFile.getParent().getFileName()).append(';\\n\\n');

// ...

// Finish the function to read the original file and add the rest of the file content,

// Also, save this back to the file.

}

}

Please complete the code inside the addPackageStatement function and handle exceptions properly while implementing the program.

This Java program provides a reliable solution to automatically add package statements to Java source files within a directory structure, ensuring proper organization and compilation.