test.groovy

// Hello World
println "Hello world!"

/*
  Variables:

  You can assign values to variables for later use
*/

def x = 1
println x

x = new java.util.Date()
println x

x = -3.1499392
println x

x = false
println x

x = "Groovy!"
println x

/*
  Collections and maps
*/

//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

// To sort without mutating original, you can do:
sortedTechnologies = technologies.sort( false )


//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')

//Get the keys of a map
println devMap.keySet()

class Foo {
    // read only property
    final String name = "Roberto"

    // read only property with public getter and protected setter
    String language
    protected void setLanguage(String language) { this.language = language }

    // dynamically typed property
    def lastName
}

/*
  Logical Branching and Looping
*/

//Groovy supports the usual if - else syntax
def x = 3

if(x==1) {
    println "One"
} else if(x==2) {
    println "Two"
} else {
    println "X greater than Two"
}

//Groovy also supports the ternary operator:
def y = 10
def x = (y > 1) ? "worked" : "failed"
assert x == "worked"

//Groovy supports 'The Elvis Operator' too!
//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 x = 0
for (i in 0 .. 30) {
    x += i
}

//Iterate over a list
x = 0
for( i in [5,3,2,1] ) {
    x += i
}

//Iterate over an array
array = (0..20).toArray()
x = 0
for (i in array) {
    x += i
}

//Iterate over a map
def map = ['name':'Roberto', 'framework':'Grails', 'language':'Groovy']
x = 0
for ( e in map ) {
    x += e.value
}

def technologies = ['Groovy','Grails','Gradle']
technologies*.toUpperCase() // = to technologies.collect { it?.toUpperCase() }

def user = User.get(1)
def username = user?.username

def clos = { println "Hello World!" }

def sum = { a, b -> println a+b }
sum(2,4)

def x = 5
def multiplyBy = { num -> num * x }
println multiplyBy(10)

def clos = { print it }
clos( "hi" )

def cl = {a, b ->
    sleep(3000) // simulate some time consuming processing
    a + b
}

mem = cl.memoize()

def callClosure(a, b) {
    def start = System.currentTimeMillis()
    mem(a, b)
    println "Inputs(a = $a, b = $b) - took ${System.currentTimeMillis() - start} msecs."
}

callClosure(1, 2)

//Another example:
import groovy.transform.TypeChecked

@TypeChecked
Integer test() {
    Integer num = "1"

    Integer[] numbers = [1,2,3,4]

    Date date = numbers[1]

    return "Test"

}

//CompileStatic example:
import groovy.transform.CompileStatic

@CompileStatic
int sum(int x, int y) {
    x + y
}

assert sum(2,5) == 7