String fileContents = new File('/path/to/file').text
If you need to specify the character encoding, use the following instead:
String fileContents = new File('/path/to/file').getText('UTF-8')
String fileContents = new File('/path/to/file').text
If you need to specify the character encoding, use the following instead:
String fileContents = new File('/path/to/file').getText('UTF-8')