How to split a file into multiple files in Kotlin

How to split a file into multiple files in Kotlin.

Here's a step-by-step tutorial on how to split a file into multiple files in Kotlin.

Read the Input File The first step is to read the contents of the input file that you want to split. You can use the File class from the java.io package to accomplish this. Here's an example:
```
val inputFile = File("input.txt")
val fileContents = inputFile.readText()
```
Define the Split Size Determine the size at which you want to split the file. This can be the number of lines, size in bytes, or any other measurement that suits your requirements. For this tutorial, let's split the file by the number of lines. You can modify this as per your needs. Here's an example:
```
val linesPerFile = 100 // Split the file into files with 100 lines each
```
Split the File Now, it's time to split the file into multiple files. Iterate over the lines of the input file and create new files as needed. Write the lines to the respective files, ensuring that each file contains the desired number of lines. Here's an example:
```
val lines = fileContents.lines()
var fileIndex = 1
var lineCount = 0

lines.forEachIndexed { index, line ->
    if (lineCount == 0 || lineCount % linesPerFile == 0) {
        val outputFile = File("output$fileIndex.txt")
        outputFile.writeText(line)
        fileIndex++
    } else {
        val outputFile = File("output$fileIndex.txt")
        outputFile.appendText("\n$line")
    }
    lineCount++
}
```
In this example, we use the forEachIndexed function to iterate over the lines of the input file. If the line count is a multiple of linesPerFile, we create a new output file (output$fileIndex.txt). Otherwise, we append the line to the existing output file.
Verify the Output After splitting the file, it's a good practice to verify the output. You can check the contents of the generated files to ensure that the splitting process worked as expected. Here's an example:
```
val outputFiles = File(".").listFiles { file ->
    file.isFile && file.name.startsWith("output")
}

outputFiles?.forEach { outputFile ->
    val fileContents = outputFile.readText()
    println("File: ${outputFile.name}")
    println(fileContents)
    println()
}
```
In this example, we use the listFiles function to get a list of all files in the current directory that start with "output". We then read and print the contents of each output file.
Handle Exceptions Remember to handle any exceptions that may occur during file operations. This includes handling FileNotFoundException, IOException, and any other exceptions that may be thrown. You can use try-catch blocks to handle these exceptions gracefully.

And that's it! You have successfully split a file into multiple files in Kotlin. Make sure to customize the code as per your specific requirements, such as file paths, splitting criteria, and error handling.