Read file

Reading a file in Groovy, a dynamic language that runs on the Java platform, is quite straightforward due to Groovy's simplified syntax and powerful features. Here are a couple of common methods you can use to read a file in Groovy:

1. Using File.text

This method is very convenient for reading small files as it directly returns the content of the file as a String.

def fileContent = new File('path/to/file.txt').text
println(fileContent)

2. Using File.eachLine

If you're dealing with larger files or if you want to process the file line by line, you can use eachLine. This method allows you to handle each line individually, which can be useful for memory management.

new File('path/to/file.txt').eachLine { line ->
    println(line)
}

3. Using InputStream

For binary files or when you need more control over the reading process (like specifying a buffer size), you can use an InputStream.

new File('path/to/file.txt').withInputStream { stream ->
    byte[] buffer = new byte[1024]
    int bytesRead
    while ((bytesRead = stream.read(buffer)) != -1) {
        // process buffer
        println(new String(buffer, 0, bytesRead))
    }
}

4. Using BufferedReader

This is another way to read large text files efficiently. BufferedReader provides a convenient way to read text from a character input stream.

new File('path/to/file.txt').withReader { reader ->
    reader.eachLine { line ->
        println(line)
    }
}

Each of these methods has its own use cases depending on your specific requirements, such as the size of the file and the type of processing needed.