Manipulating Data types

def newString = "Hello Groovy in JMWE"

//startsWith
newString.startsWith("Hello") //returns true
newString.startsWith("Groovy") //returns false

//getAt()
newString.getAt(1) == "e"
newString[0] == "H"

//indexOf
newString.indexOf("in") == 13

//contains()
newString.contains("JMWE") //returns true

//Remove a part of the String
newString - "Hello " //returns "Groovy in JMWE"

//size()
newString.size() //returns 20

//Adding spaces to the String
"a".padLeft(3) //returns "   a"
"a".padRight(3) //retunrs "a   "
"a".center(3) //returns " a "
"a"*3 //returns "aaa"

//Strip extra lines
def multiline = """
String
containing 
multiple 
lines
"""

//Get the absolute value
(-1).abs() == 1

//Transform to integer
2.5.toInteger() == 2

//Enforced coercion
2.5 as Integer == 2

//Casting a number
(int) 2.5 == 2

//Rounding
2.5f.round() == 3
Math.PI.round(3) == 3.142

//String methods on numbers
"2.718".isNumber() //returns true

//Increment by one
2.next() ==  3

//times - Repeat certain number of times
def store = ""
10.times{
 store += "x"
}
store == "xxxxxxxxxx" //returns true

//upto - Walking upto a number
def store = ""
1.upto(5) { number ->
 store += number
}
store == "12345" 

//downto - Walking down to a number
def store = ""
2.downto(-2) { number -> 
 store += number + " "
}
store == "2 1 0 -1 -2 "

//step - Walking with step width 
def store = ""
0.step(0.5, 0.1 ){ number ->
 store += number + " "
} 
store == "0 0.1 0.2 0.3 0.4 "

//String.eachMatch method
def sentence = "Rain in spain stays mainly in plain"
def wordEnding = /w*ain/
def rhyme = /b$wordEndingb/
def found = ""
sentence.eachMatch(rhyme){ match ->
  found += match + " "
}

//Matcher.each method
found = ''
(sentence =~ rhyme).each { match ->
 found += match + ' '
}
found 

//String.replaceAll(regex){}
def replace = sentence.replaceAll(rhyme){ it-'ain'+'___' }
replace 

//Logical conjuction of two boolean operators
"2.718".isNumber().and(2.718f.round() == 3)

//Coerce to a boolean value
(x=3).asBoolean()

HashSet set = [1,2,3]

//Append a value at the end of the set
set.add(4) == [1,2,3,4]

//Get an element at a specified location
set.getAt(2)

//Contains an element
set.contains(4) == true

//Check whether the set is empty
set.isEmpty() == false

//Remove an element
set.minus(3)

//Add an element
set.plus(5)

//Size of the set
set.size() == 4

//Max and min in the set
set.max() == 4
set.min() == 1

//Find for the first element matching the condition
set.find{ it > 1 } //returns 2

//Find for all elements matching the condition
set.findAll{ it > 1 } //returns [2,3,4]

//Returns true if all elements match
set.every { it < 5 }

//Returns true if any element matches
set.any { it > 2 }

HashSet set1 = ["a", "b", "c", "d", "e"]
//Find index of 1st element matching criteria
set1.findIndexOf { it in ["c", "e", "g"] } //returns 2

//Sum of all the elements
set.sum() == 21
set1.sum() == "abcde"

//Join the elements
set.join('-') == "1-2-3"
HashSet set2 = [["a", "b"],["c", "d"]]
set2.sum() == ["a", "b", "c", "d"]

def list = [1,2,3]

//Reverse a list
list.reverse() == [4, 3, 2, 1]

//Index returned
["a", "b", "c", "d", "c"].indexOf("c") == 2

//Get an element at a specified location
list.get(2)

def map = [name: "John", branch: "Electrical", id: 1234]

//Get the value of a key
map.get("name") == "John"
map["name"] == "John"
map.name == "John"

//Size of the map
map.size() == 3

//Escape key by adding paranthesis
def a = "John"
def ages = [(a):50]

ages.("John") //returns 50

//Clone a map
map2 = map.clone()

//Check the map contains a key
map.containsKey("id") == true

//Collection view of the values contained in the Map
map.values()

//Add elements
map.put("location", "Denmark")
map == [name: "John", branch: "Electrical", id: 1234, "location":"Denmark"]

def map3 = [1: "a", 2: "b", 3: "c"]
map.putAll(map3)
map == [name: "John", branch: "Electrical", id: 1234, "location":"Denmark", 1: "a", 2: "b", 3: "c"]

//Remove elements
map.clear() == null

//Obtain a Set of the keys in the Map
map.keySet()

def people = [
    1: [name:"Bob", age: 32, gender: "M"],
    2: [name:"Johnny", age: 36, gender: "M"],
    3: [name:"Claire", age: 21, gender: "F"],
    4: [name:"Amy", age: 54, gender:"F"]
]

//Find a specific element matching a condition
people.find { it.value.name == "Bob" } // returns a single entry

//Find all elements matching a condition
people.findAll { it.value.gender == "F" } //returns a Map matching the entries

//Collect specific values
def agesOfPeople = people.collect{
  it.value.age
}
agesOfPeople == [32, 36, 21, 54]

//Every - Returns true if all elements match the condition
people.every{ id, person ->
  person.age > 18
}

//Any - Returns true if any element matches the condition
people.any{ id, person ->
  person.age > 18
}

//Group a list into a map
list = ['a', 7, 'b', [2, 3]]
list.groupBy{
  it.class
}
//returns
[(String)   : ['a', 'b'],
 (Integer)  : [7],
 (ArrayList): [[2, 3]]
]

def range = (0..10)

//Contains a specific element
range.contains(3) == true

//Get a specific element
range.get(4) == 4

//Lower value of the range
range.getFrom() == 0

//Upper value of the range
range.getTo() == 10

//Size of the range
range.size() == 11

//Reverse the range
range.reverse() == 10..0