From 3060030787d582b830af32eb305fea7b57dd7c2b Mon Sep 17 00:00:00 2001
From: Mark Fisher <markfisher@vmware.com>
Date: Fri, 30 Sep 2011 10:27:19 -0400
Subject: [PATCH] Create ScriptEngine per execution

---
 .../jsr223/DefaultScriptExecutor.java         | 48 +++++++++----------
 1 file changed, 24 insertions(+), 24 deletions(-)

diff --git a/spring-integration-scripting/src/main/java/org/springframework/integration/scripting/jsr223/DefaultScriptExecutor.java b/spring-integration-scripting/src/main/java/org/springframework/integration/scripting/jsr223/DefaultScriptExecutor.java
index 0eecdc45b5..ce23ce3f77 100644
--- a/spring-integration-scripting/src/main/java/org/springframework/integration/scripting/jsr223/DefaultScriptExecutor.java
+++ b/spring-integration-scripting/src/main/java/org/springframework/integration/scripting/jsr223/DefaultScriptExecutor.java
@@ -23,18 +23,23 @@ import javax.script.ScriptException;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+
 import org.springframework.integration.scripting.ScriptExecutor;
 import org.springframework.scripting.ScriptSource;
+import org.springframework.util.Assert;
 import org.springframework.util.ClassUtils;
 
 /**
  * Executes JSR223 scripts
  * 
  * @author David Turanski
+ * @author Mark Fisher
  * @since 2.1
  */
 public class DefaultScriptExecutor implements ScriptExecutor {
 
+	private static final Log logger = LogFactory.getLog(DefaultScriptExecutor.class);
+
 	static {
 		if (ClassUtils.isPresent("org.jruby.embed.jsr223.JRubyEngine", System.class.getClassLoader())) {
 			System.setProperty("org.jruby.embed.localvariable.behavior", "transient");
@@ -42,50 +47,46 @@ public class DefaultScriptExecutor implements ScriptExecutor {
 		}
 	}
 
-	private static Log log = LogFactory.getLog(DefaultScriptExecutor.class);
 
-	private final ScriptEngine scriptEngine;
+	private final ScriptEngineManager scriptEngineManager = new ScriptEngineManager();
+
+	private final String language;
+
 
 	/**
-	 * Set the language name (JSR233 alias)
-	 * @param language
+	 * Create a DefaultScriptExceutor for the specified language name (JSR233 alias).
 	 */
 	public DefaultScriptExecutor(String language) {
-		ScriptEngineManager manager = new ScriptEngineManager();
-
-		scriptEngine = manager.getEngineByName(language);
-		if (log.isDebugEnabled()) {
-			log.debug("using script engine : " + scriptEngine.getFactory().getEngineName());
+		Assert.hasText(language, "language must not be empty");
+		this.language = language;
+		if (logger.isDebugEnabled()) {
+			logger.debug("using script engine : " + scriptEngineManager.getEngineByName(language).getFactory().getEngineName());
 		}
 	}
 
+
 	public Object executeScript(ScriptSource scriptSource) {
 		return this.executeScript(scriptSource, null);
 	}
 
-	public synchronized Object executeScript(ScriptSource scriptSource, Map<String, Object> variables) {
-		Object obj = null;
+	public Object executeScript(ScriptSource scriptSource, Map<String, Object> variables) {
+		Object result = null;
+		ScriptEngine scriptEngine = this.scriptEngineManager.getEngineByName(this.language);
 		try {
-
 			if (variables != null) {
 				for (Entry<String, Object> entry : variables.entrySet()) {
 					scriptEngine.put(entry.getKey(), entry.getValue());
 				}
 			}
-
 			String script = scriptSource.getScriptAsString();
-
 			Date start = new Date();
-			if (log.isDebugEnabled()) {
-				log.debug("executing script: " + script);
+			if (logger.isDebugEnabled()) {
+				logger.debug("executing script: " + script);
 			}
-
-			obj = scriptEngine.eval(script);
-
-			if (log.isDebugEnabled()) {
-				log.debug("script executed in " + (new Date().getTime() - start.getTime()) + " ms");
+			result = scriptEngine.eval(script);
+			if (logger.isDebugEnabled()) {
+				logger.debug("script executed in " + (new Date().getTime() - start.getTime()) + " ms");
 			}
-
 		}
 		catch (IOException e) {
 			throw new RuntimeException(e);
@@ -93,8 +94,7 @@ public class DefaultScriptExecutor implements ScriptExecutor {
 		catch (ScriptException e) {
 			throw new RuntimeException(e);
 		}
-
-		return obj;
+		return result;
 	}
 
 }