• hello world needs a class and special method
• primitive types
• arrays  are primitives, collections are objects 
• no closures/labmdas until Java8!
• read/write from/to file example
• use plain JDBC interface
• try to parse or generate XML, JSON without any library in few lines
• String API is limited, helper classes don't solve all problems
• lot's of useful code snipets are available in other libraries
• no scripting support
• no functional support

• Simplify the life of (Java) Developers
• Groovy is Java superset
• It's also easy to learn
• As safe and fast as Java with static type checking and compilation
• great for scripting
• fit for Domain-Specific Languages (DSL)
• most seamless integration & interoperability with Java
• expressive, concise readable

@RestController
class ThisWillActuallyRun {

    @RequestMapping("/")
    String home() {
        return "Hello World!"
    }

}

• semicolons
• parentheses
• typing
• public keyword
• return keyword

• implicit parameter 'it'
• explicit parameter types
• default parameter values
• methods as functions (& turns static method as a function)
• def printer = System.out.&println
• printer 'Hello world'

• Lists can be evaluated as a boolean value
  
• We can use the each and eachWithIndex methods to execute code on each item in a list
  
• [1, 2, 3].each{ println "Item: $it" }
• Other useful methods added in GDK
• assert [1, 2, 3].find{ it > 1 } == 2
  
• assert [1,2,3,4,5,6].sum() == 21
  
• ssert [1, 2, 3].join('-') == '1-2-3'
  
• We can remove elements from a list by referring to the element/s to be removed
  
• assert ['a','b','c','b','b'] - 'c' == ['a','b','b','b']
  

• other useful methods
• assert [1,2,3,3,3,3,4,5].count(3) == 4
  
• assert [1,2,3] * 3 == [1,2,3,1,2,3,1,2,3]
  
• def stack= [1,2,4,6]; stack << 7
  
• assert [1,2,4,6,8,10,12].intersect([1,3,6,9,12]) == [1,6,12]
  
• assert ! [1,2,3].disjoint( [2,4,6] )
  
• map (collect), filter (findAll), reduce (inject)

• Ranges
• assert 5..8 == [5,6,7,8] //includes both values
  
• assert 5..<8 == [5, 6, 7] //excludes specified top value
  
• Sets
• def s1= [1,2,3,3,3,4] as Set
  
• Immutable collections
• def imList= ['a', 'b', 'c'].asImmutable()
  
• Maps
• def map= ['id':'FX-11', 'name':'Radish', 'no':1234, 99:'Y']
  

• Strings, GStrings, multiline strings
• lots of useful annotations, @groovy.transform.Immutable, @Memoized, @Grab, @EqualsAndHashCode, @Singleton
• decimals represented as BigDecimal
• Date ehnancements
• def today= new Date() , tomorrow= today + 1
• regular expressions
• powerful switch/case on steroids

String fileContents = new File('/path/to/file').text
String fileContents = new File('/path/to/file').getText('UTF-8')

new File('/path/to/file').eachLine { line ->
  println line 
}

• markup, xml, json, swing
  

• Groovy DSL for testing
• Builds on JUnit 4
• Goals: Concise, maintanable 
• Given/when/then
• Data driven testing (feature testing)
• Interaction based testing (mocking and stubing)
• Spock basics

• stubs
• spies
• creating extensions
• asynchronous testing
• hamcrest assertions

• power of Selenium Webdriver 2
• elegance of jQuery content selection
• robustness of PageObject modeling
• expressiveness of Groovy
• lead by Spock

• The browser is the centre of Geb. It encapsulates a WebDriver implementation and references a Page object that provides access to the content.
• Browser objects dynamically delegate all method calls and property read/writes that it doesn't implement to the current page instance via propertyMissing() and methodMissing().