org.springframework.scripting.groovy.GroovyScriptFactory Maven / Gradle / Ivy

/*
 * Copyright 2002-2006 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.scripting.groovy;

import java.io.IOException;

import groovy.lang.GroovyClassLoader;
import org.codehaus.groovy.control.CompilationFailedException;

import org.springframework.scripting.ScriptCompilationException;
import org.springframework.scripting.ScriptFactory;
import org.springframework.scripting.ScriptSource;
import org.springframework.util.Assert;
import org.springframework.util.ClassUtils;

/**
 * {@link org.springframework.scripting.ScriptFactory} implementation
 * for a Groovy script.
 *
 * Typically used in combination with a
 * {@link org.springframework.scripting.support.ScriptFactoryPostProcessor};
 * see the latter's
 * {@link org.springframework.scripting.support.ScriptFactoryPostProcessor Javadoc}
 * for a configuration example.
 *
 * @author Juergen Hoeller
 * @author Rob Harrop
 * @since 2.0
 * @see org.springframework.scripting.support.ScriptFactoryPostProcessor
 * @see groovy.lang.GroovyClassLoader
 */
public class GroovyScriptFactory implements ScriptFactory {

	private final String scriptSourceLocator;


	/**
	 * Create a new GroovyScriptFactory for the given script source.
	 * We don't need to specify script interfaces here, since
	 * a Groovy script defines its Java interfaces itself.
	 * @param scriptSourceLocator a locator that points to the source of the script.
	 * Interpreted by the post-processor that actually creates the script.
	 * @throws IllegalArgumentException if the supplied String is empty
	 */
	public GroovyScriptFactory(String scriptSourceLocator) {
		Assert.hasText(scriptSourceLocator);
		this.scriptSourceLocator = scriptSourceLocator;
	}


	public String getScriptSourceLocator() {
		return this.scriptSourceLocator;
	}

	/**
	 * Groovy scripts determine their interfaces themselves,
	 * hence we don't need to explicitly expose interfaces here.
	 * @return null always
	 */
	public Class[] getScriptInterfaces() {
		return null;
	}

	/**
	 * Groovy scripts do not need a config interface,
	 * since they expose their setters as public methods.
	 * @return false always
	 */
	public boolean requiresConfigInterface() {
		return false;
	}

	/**
	 * Loads and parses the Groovy script via the GroovyClassLoader.
	 * @see groovy.lang.GroovyClassLoader
	 */
	public Object getScriptedObject(ScriptSource actualScriptSource, Class[] actualInterfaces)
			throws IOException, ScriptCompilationException {

		ClassLoader cl = ClassUtils.getDefaultClassLoader();
		GroovyClassLoader groovyClassLoader = new GroovyClassLoader(cl);
		try {
			Class clazz = groovyClassLoader.parseClass(actualScriptSource.getScriptAsString());
			return clazz.newInstance();
		}
		catch (CompilationFailedException ex) {
			throw new ScriptCompilationException(
					"Could not compile Groovy script: " + actualScriptSource, ex);
		}
		catch (InstantiationException ex) {
			throw new ScriptCompilationException(
					"Could not instantiate Groovy script class: " + actualScriptSource, ex);
		}
		catch (IllegalAccessException ex) {
			throw new ScriptCompilationException(
					"Could not access Groovy script constructor: " + actualScriptSource, ex);
		}
	}

}