Groovy

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TODO

  • Tutorial: www.tutorialspoint.com/groovy/index.htm

TODO Groovy basics: https://docs.gradle.org/current/userguide/writing_build_scripts.html#groovy-dsl-basics

String Programming

TODO next time I need it.

Single-Quoted vs. Double-Quoted Strings

Groovy has both double-quoted and single-quoted String literals. The main difference is that double-quoted String literals support String interpolation:

def x = 10
println "result is $x" // prints: result is 10

Working with Closures

http://groovy-lang.org/closures.html

Defining a Closure

def myClosure = { e -> println "Clicked on $e.source" }

Passing a closure to a method:

file.eachLine(line -> {
  println line
})

Implicit Paramenter

When a closure does not explicitly define a parameter using the '->' syntax, the closure 'always defines an implicit parameter named "it".

Passing Closures to Methods

If the closure is the last argument for a method, it can be passed outside the argument list.

https://mrhaki.blogspot.com/2009/11/groovy-goodness-passing-closures-to.html

Template Engines

Groovy Template Engines

Files

filename = 'example.txt'
File f = new File(filename)
def lines = f.readLines()
for (line in lines) {
    // ...
}
filename = 'example.txt'
File f = new File(filename)
f.eachLine({
 if (!it.startsWith("#") && !it.trim().isEmpty()) {
   ...
  }
})

Strings