Groovy Goodness: Define Compilation Customizers With Builder Syntax

Since Groovy 2.1 we can use a nice builder syntax to define customizers for a CompileConfiguration instance. We must use the static withConfig method of the class CompilerCustomizationBuilder in the package org.codehaus.groovy.control.customizers.builder. We pass a closure with the code to define and register the customizers. For all the different customizers like ImportCustomizer, SecureASTCustomizers and ASTTransformationCustomizer there is a nice compact syntax.

In the following sample we use this builder syntax to define different customizers for a CompileConfiguration instance:

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package com.mrhaki.blog   import org.codehaus.groovy.control.customizers.ASTTransformationCustomizer import org.codehaus.groovy.control.CompilerConfiguration import org.codehaus.groovy.control.customizers.builder.CompilerCustomizationBuilder import groovy.transform.*     def conf = new CompilerConfiguration()   // Define CompilerConfiguration using // builder syntax. CompilerCustomizationBuilder.withConfig(conf) {     ast(TupleConstructor)     ast(ToString, includeNames: true, includePackage: false)           imports {         alias 'Inet', 'java.net.URL'     }           secureAst {         methodDefinitionAllowed = false     } }     def shell = new GroovyShell(conf) shell.evaluate ''' package com.mrhaki.blog   class User {     String username, fullname }   // TupleConstructor is added. def user = new User('mrhaki', 'Hubert A. Klein Ikkink')   // toString() added by ToString transformation. assert user.toString() == 'User(username:mrhaki, fullname:Hubert A. Klein Ikkink)'   // Use alias import. def site = new Inet('http://www.mrhaki.com/') assert site.text '''

Code written with Groovy 2.2.2.