wget https://dl.bintray.com/groovy/maven/apache-groovy-binary-2.4.7.zip
unzip apache-groovy-binary-2.4.7.zip
sudo ln -s /home/osboxes/Downloads/groovy-2.4.7/bin/groovy /usr/bin/groovy
groovy -v
Groovy Version: 2.4.7 JVM: 1.8.0_91 Vendor: Oracle Corporation OS: Linux

https://learnxinyminutes.com/docs/groovy/
http://www.groovy-lang.org/index.html
https://github.com/ciandcd/jenkins-awesome/blob/master/utils/groovy_basic.gy

#!/usr/bin/env groovy// Hello World
println "Hello world!"// Variables: You can assign values to variables for later use
def x = 1
println xx = new java.util.Date()
println xx = -3.1499392
println xx = false
println xx = "Groovy!"
println x//Creating an empty list
def technologies = []/*** Adding a elements to the list ***/
// As with Java
technologies.add("Grails")// Left shift adds, and returns the list
technologies << "Groovy"// Add multiple elements
technologies.addAll(["Gradle","Griffon"])/*** Removing elements from the list ***/
// As with Java
technologies.remove("Griffon")// Subtraction works also
technologies = technologies - 'Grails'/*** Iterating Lists ***/
// Iterate over elements of a list
technologies.each { println "Technology: $it"}
technologies.eachWithIndex { it, i -> println "$i: $it"}/*** Checking List contents ***/
//Evaluate if a list contains element(s) (boolean)
contained = technologies.contains( 'Groovy' )// Or
contained = 'Groovy' in technologies// Check for multiple contents
technologies.containsAll(['Groovy','Grails'])/*** Sorting Lists ***/// Sort a list (mutates original list)
technologies.sort()// To sort without mutating original, you can do:
sortedTechnologies = technologies.sort( false )/*** Manipulating Lists ***///Replace all elements in the list
Collections.replaceAll(technologies, 'Gradle', 'gradle')//Shuffle a list
Collections.shuffle(technologies, new Random())//Clear a list
technologies.clear()//Creating an empty map
def devMap = [:]//Add values
devMap = ['name':'Roberto', 'framework':'Grails', 'language':'Groovy']
devMap.put('lastName','Perez')//Iterate over elements of a map
devMap.each { println "$it.key: $it.value" }
devMap.eachWithIndex { it, i -> println "$i: $it"}//Evaluate if a map contains a key
assert devMap.containsKey('name')//Evaluate if a map contains a value
assert devMap.containsValue('Roberto')//Get the keys of a map
println devMap.keySet()//Get the values of a map
println devMap.values()//Groovy supports the usual if - else syntax
def x1 = 3if(x1==1) {println "One"
} else if(x1==2) {println "Two"
} else {println "X greater than Two"
}//Groovy also supports the ternary operator:
def y = 10
def x2 = (y > 1) ? "worked" : "failed"
assert x2 == "worked"//Instead of using the ternary operator:
//displayName = user.name ? user.name : 'Anonymous'
//We can write it:
//displayName = user.name ?: 'Anonymous'//For loop
//Iterate over a range
def x3 = 0
for (i in 0 .. 30) {x3 += i
}//Iterate over a list
x4 = 0
for( i in [5,3,2,1] ) {x4 += i
}//Iterate over an array
array = (0..20).toArray()
x5 = 0
for (i in array) {x5 += i
}//Iterate over a map
def map = ['name':'Roberto', 'framework':'Grails', 'language':'Groovy']
x6 = 0
for ( e in map ) {x6 += e.value
}/*ClosuresA Groovy Closure is like a "code block" or a method pointer. It is a piece ofcode that is defined and then executed at a later point.More info at: http://www.groovy-lang.org/closures.html
*///Example:
def clos = { println "Hello World!" }println "Executing the Closure:"
clos()//Passing parameters to a closure
def sum = { a, b -> println a+b }
sum(2,4)//Closures may refer to variables not listed in their parameter list.
def x7 = 5
def multiplyBy = { num -> num * x7 }
println multiplyBy(10)// If you have a Closure that takes a single argument, you may omit the
// parameter definition of the Closure
def clos2 = { println it }
clos2( "hi" )/*Groovy can memoize closure results [1][2][3]
*/
def cl = {a, b ->sleep(3000) // simulate some time consuming processinga + b
}mem = cl.memoize()def callClosure(a, b) {def start = System.currentTimeMillis()println mem(a, b)println "Inputs(a = $a, b = $b) - took ${System.currentTimeMillis() - start} msecs."
}callClosure(1, 2)
callClosure(1, 2)
callClosure(2, 3)
callClosure(2, 3)
callClosure(3, 4)
callClosure(3, 4)
callClosure(1, 2)
callClosure(2, 3)
callClosure(3, 4)