Filter lines
The filterLine returns those lines where the closure returns true.
The file test.txt contains the following contents.
Hello World 1234 Hello World 1234
def file = new File("test.txt")
StringWriter writer = new StringWriter()
file.filterLine(writer) { line ->
line.contains("Hello World")
}
println writer.toString()
This groovy snippets will output the following.
Hello World Hello World 1234