Gradle templates

// Generate a new Groovy Project Qwickly (tm) //
// source: https://github.com/townsfolk/gradle-templates

// in build.gradle file (in the project's root folder):
apply from: 'http://www.tellurianring.com/projects/gradle-plugins/gradle-templates/apply.groovy'

dependencies {
   groovy localGroovy()
}

//then get a list of tasks:
>> gradle tasks

...
Template tasks
--------------
createGroovyClass - Creates a new Groovy class in the current project. **************
createGroovyProject - Creates a new Gradle Groovy project in a new directory named after your project.
createJavaClass - Creates a new Java class in the current project.
createJavaProject - Creates a new Gradle Java project in a new directory named after your project.
exportGroovyTemplates - Exports the default groovy template files into the current directory.
exportJavaTemplates - Exports the default java template files into the current directory.
initGroovyProject - Initializes a new Gradle Groovy project in the current directory. **************
initJavaProject - Initializes a new Gradle Java project in the current directory.
...


>> gradle initGroovyProject
>> gradle createGroovyClass


/**********************************************************/

//Here's a pretty useful project build.gradle:
apply plugin: 'groovy'
apply from: 'http://www.tellurianring.com/projects/gradle-plugins/gradle-templates/apply.groovy'
apply from: 'http://evgenyg.artifactoryonline.com/evgenyg/libs-releases-local/CodeNarc.gradle'

group = 'myapp1'
mainClassName = 'org.MyCompany.Main'

dependencies {
   groovy localGroovy()
}

jar {
    manifest {
        attributes("Main-Class": mainClassName)
    }
}

// uberjar adds in groovy jars to make this easy: "java -jar MyApp.jar"
task uberjar(type: Jar, dependsOn:[':compileJava', ':compileGroovy']) {
    from files(sourceSets.main.output.classesDir)
    from configurations.runtime.asFileTree.files.collect { zipTree(it) }

    manifest {
        attributes 'Main-Class': mainClassName
    }
}

Script template

// this is just intended to give a little more OOP structure to a script.
// put most code inside of run(), plus class variables and methods.

class Script {
    
    private String hello = "Hello"
    
    public Script run(Map options = [:]) {
        println "$hello ${options.name ?: 'World'}${shout(23)}"
        
        
        return this // for method chaining
    }
    
    private String shout(int times = 1) {
        return ('!' * times)
    }
    
}

new Script()
    .run()
    .run([name:'Crazy4Groovy'])

println 'DONE'

Simple Performance Benchmarking

int delayMillis = 100

Long startMillis = Calendar.instance.time.time

Thread.sleep(delayMillis)

Long passedMillis = Calendar.instance.time.time - startMillis

println passedMillis

assert passedMillis >= delayMillis

XML StreamingMarkupBuilder

import groovy.xml.StreamingMarkupBuilder

Map props = [addressid:'1', line1:'line-1_VALUE', line2:'line-2_VALUE']

def builder = new StreamingMarkupBuilder()

def address = {
     "address"(id: props.addressid) {
         "line-1"(props.line1)
         "line-2"(props.line2)
         "city"("city_VALUE") // typing wimped out...
         "state"("State_VALUE")
         "postal-code"("postal_VALUE")
     }
}

println builder.bind(address).toString() // something XML-compatible <address id="1">
...</address>

Scrape image src's from a web page

import java.net.URLEncoder

String url = "http://msnbc.com"

String serviceUrl = "http://query.yahooapis.com/v1/public/yql?q=select%20*%20from%20html%20where%20url%3D%22${URLEncoder.encode(url)}%22%20and%20xpath%3D%22%2F%2Fimg%22"
//println serviceUrl

String resultXML = serviceUrl.toURL().text // YQL will return the HTML page as XML!
//println resultXML

def root = new XmlSlurper().parseText(resultXML)

List imgSrcs = root.results.img.@src as List
imgSrcs = imgSrcs*.toString().unique()
//println imgSrcs.join('\n')

Immutable Maps (and Lists)

//source: http://royontechnology.blogspot.co.at/2010/06/creating-collection-with-single-element.html

//note the different constructor args; both return immutables

assert [2] == Collections.singletonMap(1, 1).collect {k,v ->
    return k+v
}

assert [3, 7] == Collections.unmodifiableMap([1:2, 3:4]).collect {k,v ->
    return k+v
}