Groovy

• https://groovy-lang.org/

Apache Groovy is a powerful, optionally typed and dynamic language, with static-typing and static compilation capabilities, for the Java platform aimed at improving developer productivity thanks to a concise, familiar and easy to learn syntax

• https://dl.bintray.com/groovy/maven/apache-groovy-binary-3.0.3.zip

Install

   1 cp apache-groovy-binary-3.0.3.zip ~/
   2 cd  ~/
   3 unzip  apache-groovy-binary-3.0.3.zip 
   4 nano ~/.bashrc
   5 # export GROOVY_HOME=$HOME/groovy-3.0.3
   6 # PATH=/usr/local/bin:/usr/bin:/bin:/usr/local/games:/usr/games:/home/user/jdk-11.0.2/bin:/home/user/scripts
   7 # PATH=$PATH:/opt/mssql-tools/bin/:$GROOVY_HOME/bin
   8 # export PATH
   9 . ~/.bashrc 
  10 groovysh
  11 # print("aaa")
  12 groovyConsole

groovyc - compiler

• nano MyClass.groovy

class X{
  int amount
}

def x = new X()
x.amount = 1
println("${x.amount}")

• groovyc MyClass.groovy

• java -cp . -jar $GROOVY_HOME/lib/groovy-3.0.3.jar MyClass

• java -jar $GROOVY_HOME/lib/groovy-3.0.3.jar MyClass

swing - groovy

import groovy.swing.SwingBuilder
import java.awt.BorderLayout as BL

count = 0

def actionPerformedFn(){
  count++; 
  textlabel.text = "Clicked ${count} time(s)."
  println "clicked"
}

def quitFn(){
  System.exit(0) 
}

new SwingBuilder().edt {
  frame(title: 'Frame', size: [300, 300], show: true) {
    borderLayout()
    textlabel = label(text: 'Click the button!', constraints: BL.NORTH)
    button(text:'Click Me', actionPerformed: {actionPerformedFn()}, constraints:BL.WEST)
    button(text:'Quit', actionPerformed: {quitFn()}, constraints:BL.EAST)
  }
}

• groovyc swing.groovy
• java -cp .:$GROOVY_HOME/lib/groovy-3.0.3.jar:$GROOVY_HOME/lib/groovy-swing-3.0.3.jar swing