INT-1552 doc polishing, also updated Groovy-based Control Bus to be more consistent with the SpEL version

spring-integration-groovy/src/main/java/org/springframework/integration/groovy/GroovyCommandMessageProcessor.java

@@ -0,0 +1,74 @@
+/*
+ * Copyright 2002-2010 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.integration.groovy;
+
+import groovy.lang.GString;
+
+import java.util.Map;
+
+import org.springframework.integration.Message;
+import org.springframework.integration.handler.AbstractScriptExecutingMessageProcessor;
+import org.springframework.scripting.ScriptSource;
+import org.springframework.scripting.groovy.GroovyObjectCustomizer;
+import org.springframework.scripting.groovy.GroovyScriptFactory;
+import org.springframework.scripting.support.StaticScriptSource;
+import org.springframework.util.Assert;
+
+/**
+ * @author Dave Syer
+ * @author Mark Fisher
+ * @since 2.0
+ */
+public class GroovyCommandMessageProcessor extends AbstractScriptExecutingMessageProcessor<Object> {
+
+	private final GroovyObjectCustomizer customizer;
+
+
+	public GroovyCommandMessageProcessor() {
+		this((GroovyObjectCustomizer) null);
+	}
+
+	public GroovyCommandMessageProcessor(Map<String, ?> map) {
+		this(new MapContextBindingCustomizer(map));
+	}
+
+	public GroovyCommandMessageProcessor(GroovyObjectCustomizer customizer) {
+		this.customizer = customizer;
+	}
+
+
+	@Override
+	protected ScriptSource getScriptSource(Message<?> message) {
+		Object payload = message.getPayload();
+		Assert.isInstanceOf(String.class, payload, "Payload must be a String containing a Groovy script.");
+		String className = generateScriptName(message);
+		return new StaticScriptSource((String) payload, className);
+	}
+
+	@Override
+	protected Object executeScript(ScriptSource scriptSource, Message<?> message) throws Exception {
+		// Keeping everything local prevents PermGen (class instances) leaks...
+		MessageContextBindingCustomizer bindingCustomizer = new MessageContextBindingCustomizer(this.customizer);
+		bindingCustomizer.setMessage(message);
+		GroovyScriptFactory scriptFactory = new GroovyScriptFactory(this.getClass().getSimpleName(), bindingCustomizer);
+		Object result = scriptFactory.getScriptedObject(scriptSource, null);
+		return (result instanceof GString) ? result.toString() : result;
+	}
+
+	protected String generateScriptName(Message<?> message) {
+		// Don't use the same script (class) name for all invocations by default
+		return getClass().getSimpleName() + message.getHeaders().getId().toString().replaceAll("-", "");
+	}
+
+}