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org.exoplatform.services.script.groovy.GroovyScriptInstantiator is part of the exo.core.component.script.groovy project. GroovyScriptInstantiator can load script from specified URL and parse stream that contains Groovy source code. It has possibility of injecting the component from Container in the Groovy Class constructor. See the configuration example:
<component>
<type>org.exoplatform.services.script.groovy.GroovyScriptInstantiator</type>
</component>