Java Programmer looking at Groovy

Some things that might help you when looking over Groovy code with "Java" eyes:

• everything is an object!
• method parenthesis are optional
• semicolons at the end of the line are optional
• elements in brackets are either a List() or a Map()
• Lists are comma separated elements
• def myList = ["one", "two", "three"]
• Maps are name value : pairs separated by commas
• def myMap = [dairy:"cheese", meat:"chicken", shopper:"Mario"]
• the return keyword is optional
• by default the result of the last statement in a code block is returned
• The questionmark protects you from null pointer exceptions
• println myObj?.myAttribute will print myAttribute if myObj is not null, no error thrown
• Strings can be single or double quoted
• Double quoted strings can have variables nested with using the ${ var } syntax or simply $var
• def var = "Crusty"
• println "The clown $var unnerves me"
• The ampersand allows you to call a method from an object
• println myObj.&someMethod
• The at symbol allows you to directly address a classes attribute
• myObj.@fieldName = "somevalue"
• A range of elements can be defined using an elipsis
• (1..10).each {println "toe number $it"}
• Now that opened up a couple of other items....
• Code in braces is called a closure (see other blog "What are Groovy Closures?")
• the keyword "it" is the default iterator for a closure
• The double less than symbol is used for appending with StringBuffer, Lists, Sockets, Files & Writers
• Named Parameters
  
• For example, create a new user with a name and ssn provided
  
• new User (name:"Gorge", ssn: "123-45-9999")
  
• Parameter Defaults
• def myMethod (String name, String type="chef") { //somecodehere }
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