Articles

• Hello World in Groovy print, println
• Reading from STDIN in Groovy Console, System, readLine, System.in.newReader().readLine() as Integer
• Groovy types boolean, int, byte, Integer
• Groovy: Undeclared variable - runtime exception - groovy.lang.MissingPropertyException def, MissingPropertyException
• Groovy: Number guessing game Random, nextInt, System.in.newReader().readLine
• Determine type of an object in Groovy instanceof, getClass
• Lists in Groovy List, ArrayList, LinkedList, size, for, each, eachWithIndex, count
• Sum of numbers File, readLines, LineNumberReader, newReader, readLine
• Solution to the "Color selector" exercise
• Read CSV file in Groovy @Grab, import, File, getText, parseCSV, separators, readFirstLine
• Solution to the count digits exercies
• reading and writing files - appending content in Groovy File, getText, readLines, newReader, readLine, write, append
• listing the content of a directory, traversing a directory tree eachFile, eachFileRecurse
• Groovy - Regular Expressions - regexes
• Groovy map (dictionary, hash, associative array) map, containsKey, key, value, keySet, sort (keys, values)
• Groovy Read/Write JSON files
• Groovy: Date, Time, Timezone
• Groovy: import and use functions from another file
• Groovy: Random numbers, random selection from list of values
• Groovy: Closures
• Groovy: remove spaces from a string (replaceAll)
• Groovy: temporary file with auto delete (File, createTempFile, deleteOnExit, absolutePath)
• Groovy: relative path (SourceURI, Path, Paths, get, getParent, resolveSibling)
• Return multiple values from a function
• String length
• Substring
• for loop - break - continue
• Groovy code reuse
• Groovy functions
• Groovy: evaluate code in another file
• Groovy classes
• Groovy function overloading
• Groovy variable scope (def)
• Recursive functions
• Groovy command line arguments (args)
• Command line parameters
• Groovy exit - System.exit - early exit from Groovy script
• Groovy file and directory attributes File, canExecute, isFile, isDirectory
• Groovy join elements of array (join)
• Groovy pop push
• Groovy: Formatted printing with printf and sprintf
• Groovy system properties
• Groovy path to current executable script
• Exception handling (try, catch, Exception)
• Throw (raise) exception
• Casting Integer, String, ...
• Printing Unicode characters from Groovy
• Import standard libraries
• Iterate over map keys
• Get the list of keys of a map as an ArrayList
• STDOUT/STDERR
• Read/Write YAML files
• Read/Write INI files
• Read/Write XML files
• HTTP request

Other resources

• Learn X in Y minutes Where X=Groovy
• Documentation of Groovy

examples/groovy/enum_planets.groovy

enum planets {
   Mercury,
   Venus,
   Earth,
   Mars,
   Jupiter,
   Saturn,
   Uranus,
   Neptune
}

println("hi")

println(planets)
println(planets.Earth)

Elapsed time

examples/groovy/elapsed_time.groovy

import groovy.time.TimeCategory
import groovy.time.TimeDuration

def start = new Date()
println(start)
print("Press any key ...")
def name = System.in.newReader().readLine()
def stop = new Date()
println(stop)
diff = stop - start
println(diff)


TimeDuration td = TimeCategory.minus( stop, start )
println td

Groovy regex

1) Interpolation can be used 2) matcher.matches vs being null ? 3) \b to mark end of word

def exp = 'line'

def matcher = (text =~ /\b$exp\b/)
println("hi")
if (matcher) {
    println("match")
}

groovy time duration - elapsed time

import groovy.time.TimeDuration

tdx = new TimeDuration(0, 0 , 0, 2000)
println(tdx)

http://docs.groovy-lang.org/2.4.9/html/gapi/groovy/time/TimeDuration.html

duration:

println(currentBuild.getClass()) //  class org.jenkinsci.plugins.workflow.support.steps.build.RunWrapper  https://javadoc.jenkins.io/plugin/workflow-support/org/jenkinsci/plugins/workflow/support/steps/build/RunWrapper.html
println("duration: ${currentBuild.durationString}") // duration: 0.35 sec and counting
println(currentBuild.getDuration()) //  397   (miliseconds)
println(currentBuild.getDurationString()) // 0.4 sec and counting

https://stackoverflow.com/questions/51788139/how-to-get-jenkins-build-job-duration