polishing, also fixed concurrency issue in XsltPayloadTransfomer.buildTransformer() method (assigning rootObject to instance var SpEL EvaluationContext)

spring-integration-xml/src/main/java/org/springframework/integration/xml/transformer/MarshallingTransformer.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2009 the original author or authors.
+ * 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.
@@ -46,8 +46,7 @@ public class MarshallingTransformer extends AbstractTransformer {
 	private volatile boolean extractPayload = true;
 
 
-	public MarshallingTransformer(Marshaller marshaller, ResultTransformer resultTransformer)
-			throws ParserConfigurationException {
+	public MarshallingTransformer(Marshaller marshaller, ResultTransformer resultTransformer) throws ParserConfigurationException {
 		Assert.notNull(marshaller, "a marshaller is required");
 		this.marshaller = marshaller;
 		this.resultTransformer = resultTransformer;
@@ -89,9 +88,6 @@ public class MarshallingTransformer extends AbstractTransformer {
 		catch (IOException e) {
 			throw new MessagingException("Failed to marshal payload", e);
 		}
-		if (transformedPayload == null) {
-			throw new MessagingException("Failed to transform payload");
-		}
 		if (this.resultTransformer != null) {
 			transformedPayload = this.resultTransformer.transformResult(result);
 		}

spring-integration-xml/src/main/java/org/springframework/integration/xml/transformer/ResultToDocumentTransformer.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2008 the original author or authors.
+ * 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.
@@ -24,11 +24,12 @@ import javax.xml.parsers.ParserConfigurationException;
 import javax.xml.transform.Result;
 import javax.xml.transform.dom.DOMResult;
 
-import org.springframework.integration.MessagingException;
-import org.springframework.xml.transform.StringResult;
 import org.w3c.dom.Document;
 import org.xml.sax.InputSource;
 
+import org.springframework.integration.MessagingException;
+import org.springframework.xml.transform.StringResult;
+
 /**
  * Creates a {@link Document} from a {@link Result} payload. Supports
  * {@link DOMResult} and {@link StringResult} implementations.
@@ -40,6 +41,7 @@ public class ResultToDocumentTransformer implements ResultTransformer {
 	// Not guaranteed to be thread safe
 	private final DocumentBuilderFactory documentBuilderFactory;
 
+
 	public ResultToDocumentTransformer(DocumentBuilderFactory documentBuilderFactory) {
 		this.documentBuilderFactory = documentBuilderFactory;
 	}
@@ -49,40 +51,41 @@ public class ResultToDocumentTransformer implements ResultTransformer {
 		this.documentBuilderFactory.setNamespaceAware(true);
 	}
 
-	public Object transformResult(Result res) {
-		Document doc = null;
-		if (DOMResult.class.isAssignableFrom(res.getClass())) {
-			doc = createDocumentFromDomResult((DOMResult) res);
+
+	public Object transformResult(Result result) {
+		Document document = null;
+		if (DOMResult.class.isAssignableFrom(result.getClass())) {
+			document = createDocumentFromDomResult((DOMResult) result);
 		}
-		else if (StringResult.class.isAssignableFrom(res.getClass())) {
-			doc = createDocumentFromStringResult((StringResult) res);
+		else if (StringResult.class.isAssignableFrom(result.getClass())) {
+			document = createDocumentFromStringResult((StringResult) result);
 		}
 		else {
-			throw new MessagingException("Failed to create document from payload type [" + res.getClass().getName()
-					+ "]");
+			throw new MessagingException("failed to create document from payload type [" +
+					result.getClass().getName() + "]");
 		}
-		return doc;
+		return document;
 	}
 
-	protected Document createDocumentFromDomResult(DOMResult domResult) {
+	private Document createDocumentFromDomResult(DOMResult domResult) {
 		return (Document) domResult.getNode();
 	}
 
-	protected Document createDocumentFromStringResult(StringResult stringResult) {
+	private Document createDocumentFromStringResult(StringResult stringResult) {
 		try {
 			return getDocumentBuilder().parse(new InputSource(new StringReader(stringResult.toString())));
 		}
 		catch (Exception e) {
-			throw new MessagingException("Failed to create Document from StringResult payload", e);
+			throw new MessagingException("failed to create Document from StringResult payload", e);
 		}
 	}
 
-	protected synchronized DocumentBuilder getDocumentBuilder() {
+	private synchronized DocumentBuilder getDocumentBuilder() {
 		try {
 			return this.documentBuilderFactory.newDocumentBuilder();
 		}
 		catch (ParserConfigurationException e) {
-			throw new MessagingException("Failed to create a new DocumentBuilder", e);
+			throw new MessagingException("failed to create a new DocumentBuilder", e);
 		}
 	}
 

spring-integration-xml/src/main/java/org/springframework/integration/xml/transformer/ResultToStringTransformer.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2007 the original author or authors.
+ * 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.
@@ -13,11 +13,9 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package org.springframework.integration.xml.transformer;
 
-import javax.xml.parsers.DocumentBuilder;
-import javax.xml.parsers.DocumentBuilderFactory;
-import javax.xml.parsers.ParserConfigurationException;
 import javax.xml.transform.Result;
 import javax.xml.transform.Transformer;
 import javax.xml.transform.TransformerConfigurationException;
@@ -30,62 +28,49 @@ import org.springframework.integration.MessagingException;
 import org.springframework.xml.transform.StringResult;
 
 /**
- * Converts the passed {@link Result} to an instance of {@link String}
- * 
+ * Converts the passed {@link Result} to an instance of {@link String}.
  * Supports {@link StringResult} and {@link DOMResult}
  * 
  * @author Jonas Partner
- * 
+ * @author Mark Fisher
  */
 public class ResultToStringTransformer implements ResultTransformer {
 
-	private DocumentBuilderFactory docBuilderFactory;
+	private final TransformerFactory transformerFactory;
 
-	private TransformerFactory transformerFactory;
 
 	public ResultToStringTransformer() {
-		this.docBuilderFactory = DocumentBuilderFactory.newInstance();
-		this.docBuilderFactory.setNamespaceAware(true);
 		this.transformerFactory = TransformerFactory.newInstance();
 	}
 
-	protected Transformer getNewTransformer()
-			throws TransformerConfigurationException {
-		synchronized (transformerFactory) {
-			return transformerFactory.newTransformer();
-		}
-	}
 
-	public Object transformResult(Result res) {
+	public Object transformResult(Result result) {
 		String returnString = null;
-		if (res instanceof StringResult) {
-			returnString = ((StringResult) res).toString();
-		} else if (res instanceof DOMResult) {
+		if (result instanceof StringResult) {
+			returnString = ((StringResult) result).toString();
+		}
+		else if (result instanceof DOMResult) {
 			try {
-				StringResult strRes = new StringResult();
-				getNewTransformer().transform(
-						new DOMSource(((DOMResult) res).getNode()), strRes);
-				returnString = strRes.toString();
-			} catch (TransformerException transE) {
-				throw new MessagingException(
-						"Transformation from DOMSOurce failed", transE);
+				StringResult stringResult = new StringResult();
+				this.getNewTransformer().transform(
+						new DOMSource(((DOMResult) result).getNode()), stringResult);
+				returnString = stringResult.toString();
+			}
+			catch (TransformerException e) {
+				throw new MessagingException("failed to transform from DOMSource failed", e);
 			}
 		}
-
 		if (returnString == null) {
-			throw new MessagingException("Could not convert Result type "
-					+ res.getClass().getName() + " to string");
+			throw new MessagingException("failed to convert Result type ["
+					+ result.getClass().getName() + "] to string");
 		}
-
 		return returnString;
 	}
 
-	protected DocumentBuilder getNewDocumentBuilder()
-			throws ParserConfigurationException {
-		synchronized (docBuilderFactory) {
-			return docBuilderFactory.newDocumentBuilder();
+	private Transformer getNewTransformer() throws TransformerConfigurationException {
+		synchronized (this.transformerFactory) {
+			return this.transformerFactory.newTransformer();
 		}
-
 	}
 
 }

spring-integration-xml/src/main/java/org/springframework/integration/xml/transformer/ResultTransformer.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2007 the original author or authors.
+ * 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.
@@ -13,10 +13,16 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package org.springframework.integration.xml.transformer;
 
+import javax.xml.transform.Result;
+
+/**
+ * @author Jonas Partner
+ */
 public interface ResultTransformer {
 
-	Object transformResult(javax.xml.transform.Result res);
+	Object transformResult(Result result);
 
 }

spring-integration-xml/src/main/java/org/springframework/integration/xml/transformer/SourceCreatingTransformer.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2008 the original author or authors.
+ * 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.
@@ -41,6 +41,7 @@ public class SourceCreatingTransformer extends AbstractPayloadTransformer<Object
 		this.sourceFactory = sourceFactory;
 	}
 
+
 	@Override
 	public Source transformPayload(Object payload) {
 		return this.sourceFactory.createSource(payload);

spring-integration-xml/src/main/java/org/springframework/integration/xml/transformer/UnmarshallingTransformer.java

@@ -50,12 +50,12 @@ import org.springframework.xml.transform.StringSource;
  */
 public class UnmarshallingTransformer extends AbstractPayloadTransformer<Object, Object> {
 
-	private volatile boolean alwaysUseSourceFactory = false;
-
 	private final Unmarshaller unmarshaller;
 
 	private volatile SourceFactory sourceFactory = new DomSourceFactory();
 
+	private volatile boolean alwaysUseSourceFactory = false;
+
 
 	public UnmarshallingTransformer(Unmarshaller unmarshaller) {
 		this.unmarshaller = unmarshaller;
@@ -63,22 +63,21 @@ public class UnmarshallingTransformer extends AbstractPayloadTransformer<Object,
 
 
 	/**
-	 * If true always delegate to the {@link SourceFactory}.
-	 * 
-	 * @param alwaysUseSourceFactory
-	 */
-	public void setAlwaysUseSourceFactory(boolean alwaysUseSourceFactory) {
-		this.alwaysUseSourceFactory = alwaysUseSourceFactory;
-	}
-
-	/**
-	 * @param sourceFactory
+	 * Provide the SourceFactory to be used. Must not be null.
 	 */
 	public void setSourceFactory(SourceFactory sourceFactory) {
 		Assert.notNull(sourceFactory, "sourceFactory must not be null");
 		this.sourceFactory = sourceFactory;
 	}
 
+	/**
+	 * If true always delegate to the {@link SourceFactory}.
+	 */
+	public void setAlwaysUseSourceFactory(boolean alwaysUseSourceFactory) {
+		this.alwaysUseSourceFactory = alwaysUseSourceFactory;
+	}
+
+
 	@Override
 	public Object transformPayload(Object payload) {
 		Source source = null;

spring-integration-xml/src/main/java/org/springframework/integration/xml/transformer/XPathHeaderEnricher.java

@@ -31,7 +31,7 @@ import org.springframework.xml.xpath.XPathExpressionFactory;
 
 /**
  * Transformer implementation that evaluates XPath expressions against the
- * message payload and inserts the result of the evaluation into a messsage
+ * message payload and inserts the result of the evaluation into a message
  * header. The header names will match the keys in the map of expressions.
  * 
  * @author Jonas Partner
@@ -49,7 +49,7 @@ public class XPathHeaderEnricher extends HeaderEnricher {
 	}
 
 
-	public static class XPathExpressionEvaluatingHeaderValueMessageProcessor implements HeaderValueMessageProcessor<Object> {
+	static class XPathExpressionEvaluatingHeaderValueMessageProcessor implements HeaderValueMessageProcessor<Object> {
 
 		private final XPathExpression expression;
 

spring-integration-xml/src/main/java/org/springframework/integration/xml/transformer/XsltHeaders.java

@@ -1,35 +0,0 @@
-/*
- * 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.xml.transformer;
-
-import javax.xml.transform.Transformer;
-
-/**
- * Message headers that can be used to configure the {@link Transformer}
- * instance used for XSL transformation.
- * 
- * @author Jonas Partner
- */
-public abstract class XsltHeaders {
-
-	public static final String PREFIX = "xslt_";
-
-	public static final String OUTPUT_PROPERTY = PREFIX +  "output_property_";
-
-	public static final String PARAMETER = PREFIX +  "parameter_";
-
-}

spring-integration-xml/src/main/java/org/springframework/integration/xml/transformer/XsltPayloadTransformer.java

@@ -13,6 +13,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package org.springframework.integration.xml.transformer;
 
 import java.io.IOException;
@@ -44,6 +45,7 @@ import org.springframework.integration.xml.result.ResultFactory;
 import org.springframework.integration.xml.source.DomSourceFactory;
 import org.springframework.integration.xml.source.SourceFactory;
 import org.springframework.util.Assert;
+import org.springframework.util.ObjectUtils;
 import org.springframework.util.PatternMatchUtils;
 import org.springframework.xml.transform.StringResult;
 import org.springframework.xml.transform.StringSource;
@@ -76,8 +78,11 @@ import org.w3c.dom.Document;
 public class XsltPayloadTransformer extends AbstractTransformer {
 
 	private final Log logger = LogFactory.getLog(this.getClass());
+
 	private final Templates templates;
-	private final StandardEvaluationContext context = new StandardEvaluationContext();
+
+	private final StandardEvaluationContext evaluationContext = new StandardEvaluationContext();
+
 	private Map<String, Expression> xslParameterMappings;
 
 	private final ResultTransformer resultTransformer;
@@ -88,17 +93,13 @@ public class XsltPayloadTransformer extends AbstractTransformer {
 
 	private volatile boolean alwaysUseSourceResultFactories = false;
 
-	private String[] xsltParamHeaders;
+	private volatile String[] xsltParamHeaders;
+
 
 	public XsltPayloadTransformer(Templates templates) throws ParserConfigurationException {
 		this(templates, null);
 	}
 
-	public XsltPayloadTransformer(Templates templates, ResultTransformer resultTransformer) throws ParserConfigurationException {
-		this.templates = templates;
-		this.resultTransformer = resultTransformer;
-	}
-
 	public XsltPayloadTransformer(Resource xslResource) throws Exception {
 		this(TransformerFactory.newInstance().newTemplates(createStreamSourceOnResource(xslResource)), null);
 	}
@@ -107,28 +108,18 @@ public class XsltPayloadTransformer extends AbstractTransformer {
 		this(TransformerFactory.newInstance().newTemplates(createStreamSourceOnResource(xslResource)), resultTransformer);
 	}
 
-
-	/**
-	 * Compensate for the fact that a Resource <i>may</i> not be a File or even
-	 * addressable through a URI. If it is, we want the created StreamSource to
-	 * read other resources relative to the provided one. If it isn't, it loads
-	 * from the default path.
-	 */
-	private static StreamSource createStreamSourceOnResource(Resource xslResource) throws IOException {
-		try {
-			String systemId = xslResource.getURI().toString();
-			return new StreamSource(xslResource.getInputStream(), systemId);
-		}
-		catch (IOException e) {
-			return new StreamSource(xslResource.getInputStream());
-		}
+	public XsltPayloadTransformer(Templates templates, ResultTransformer resultTransformer) throws ParserConfigurationException {
+		this.templates = templates;
+		this.resultTransformer = resultTransformer;
+		this.evaluationContext.addPropertyAccessor(new MapAccessor());
 	}
 
+
 	/**
 	 * Sets the SourceFactory.
 	 */
 	public void setSourceFactory(SourceFactory sourceFactory) {
-		Assert.notNull(sourceFactory, "SourceFactory can not be null");
+		Assert.notNull(sourceFactory, "SourceFactory must not be null");
 		this.sourceFactory = sourceFactory;
 	}
 
@@ -136,7 +127,7 @@ public class XsltPayloadTransformer extends AbstractTransformer {
 	 * Sets the ResultFactory
 	 */
 	public void setResultFactory(ResultFactory resultFactory) {
-		Assert.notNull(sourceFactory, "ResultFactory can not be null");
+		Assert.notNull(sourceFactory, "ResultFactory must not be null");
 		this.resultFactory = resultFactory;
 	}
 
@@ -144,8 +135,20 @@ public class XsltPayloadTransformer extends AbstractTransformer {
 	 * Specifies whether {@link ResultFactory} and {@link SourceFactory} should always
 	 * be used, even for directly supported payloads such as {@link String} and {@link Document}.
 	 */
-	public void setAlwaysUseSourceResultFactories(boolean alwaysUserSourceResultFactories) {
-		this.alwaysUseSourceResultFactories = alwaysUserSourceResultFactories;
+	public void setAlwaysUseSourceResultFactories(boolean alwaysUseSourceResultFactories) {
+		this.alwaysUseSourceResultFactories = alwaysUseSourceResultFactories;
+	}
+
+	public void setXslParameterMappings(Map<String, Expression> xslParameterMappings) {
+		this.xslParameterMappings = xslParameterMappings;
+	}
+
+	public void setXsltParamHeaders(String[] xsltParamHeaders) {
+		this.xsltParamHeaders = xsltParamHeaders;
+	}
+
+	public String getComponentType() {
+		return "xml:xslt-transformer";
 	}
 
 	@Override
@@ -172,29 +175,29 @@ public class XsltPayloadTransformer extends AbstractTransformer {
 		return transformedPayload;
 	}
 
-	protected Object transformUsingFactories(Object payload, Transformer transformer) throws TransformerException {
-		Source source = sourceFactory.createSource(payload);
+	private Object transformUsingFactories(Object payload, Transformer transformer) throws TransformerException {
+		Source source = this.sourceFactory.createSource(payload);
 		return transformSource(source, payload, transformer);
 	}
 
-	protected Object transformSource(Source source, Object payload, Transformer transformer) throws TransformerException {
-		Result result = resultFactory.createResult(payload);
+	private Object transformSource(Source source, Object payload, Transformer transformer) throws TransformerException {
+		Result result = this.resultFactory.createResult(payload);
 		transformer.transform(source, result);
-		if (resultTransformer != null) {
-			return resultTransformer.transformResult(result);
+		if (this.resultTransformer != null) {
+			return this.resultTransformer.transformResult(result);
 		}
 		return result;
 	}
 
-	protected String transformString(String stringPayload, Transformer transformer) throws TransformerException {
+	private String transformString(String stringPayload, Transformer transformer) throws TransformerException {
 		StringResult result = new StringResult();
 		transformer.transform(new StringSource(stringPayload), result);
 		return result.toString();
 	}
 
-	protected Document transformDocument(Document documentPayload, Transformer transformer) throws TransformerException {
+	private Document transformDocument(Document documentPayload, Transformer transformer) throws TransformerException {
 		DOMSource source = new DOMSource(documentPayload);
-		Result result = resultFactory.createResult(documentPayload);
+		Result result = this.resultFactory.createResult(documentPayload);
 		if (!DOMResult.class.isAssignableFrom(result.getClass())) {
 			throw new MessagingException(
 					"Document to Document conversion requires a DOMResult-producing ResultFactory implementation.");
@@ -203,51 +206,52 @@ public class XsltPayloadTransformer extends AbstractTransformer {
 		transformer.transform(source, domResult);
 		return (Document) domResult.getNode();
 	}
-	
-	protected Transformer buildTransformer(Message<?> message) throws TransformerException {
+
+	private Transformer buildTransformer(Message<?> message) throws TransformerException {
 		//process  individual mappings
 		Transformer transformer = this.templates.newTransformer();
-		context.setRootObject(message);
-		context.addPropertyAccessor(new MapAccessor());
-		if (xslParameterMappings != null){
-			for (String parameterName: xslParameterMappings.keySet()) {
-				Expression expression = xslParameterMappings.get(parameterName);
-				Object value = null;
+		if (this.xslParameterMappings != null){
+			for (String parameterName: this.xslParameterMappings.keySet()) {
+				Expression expression = this.xslParameterMappings.get(parameterName);
 				try {
-					value = expression.getValue(context);
+					Object value = expression.getValue(this.evaluationContext, message);
 					transformer.setParameter(parameterName, value);
-				} catch (Exception e) {
-					logger.warn("Header expression '" + expression.getExpressionString() + "' can not resolve within current message and will not be mapped to XSLT parameter");
-				}		
+				}
+				catch (Exception e) {
+					if (logger.isWarnEnabled()) {
+						logger.warn("Evaluation of header expression '" + expression.getExpressionString() +
+								"' failed. The XSLT parameter '" + parameterName + "' will be skipped.");
+					}
+				}
 			}
 		}
 		// process xslt-parameter-headers
 		MessageHeaders headers =  message.getHeaders();
-		if (xsltParamHeaders != null){
+		if (!ObjectUtils.isEmpty(this.xsltParamHeaders)) {
 			for (String headerName : headers.keySet()) {
-				if (PatternMatchUtils.simpleMatch(xsltParamHeaders, headerName)){
+				if (PatternMatchUtils.simpleMatch(this.xsltParamHeaders, headerName)) {
 					transformer.setParameter(headerName, headers.get(headerName));
-				}			
+				}
 			}
 		}
 		return transformer;
 	}
 
-	public Map<String, Expression> getXslParameterMappings() {
-		return xslParameterMappings;
+
+	/**
+	 * Compensate for the fact that a Resource <i>may</i> not be a File or even
+	 * addressable through a URI. If it is, we want the created StreamSource to
+	 * read other resources relative to the provided one. If it isn't, it loads
+	 * from the default path.
+	 */
+	private static StreamSource createStreamSourceOnResource(Resource xslResource) throws IOException {
+		try {
+			String systemId = xslResource.getURI().toString();
+			return new StreamSource(xslResource.getInputStream(), systemId);
+		}
+		catch (IOException e) {
+			return new StreamSource(xslResource.getInputStream());
+		}
 	}
 
-	public void setXslParameterMappings(Map<String, Expression> xslParameterMappings) {
-		this.xslParameterMappings = xslParameterMappings;
-	}
-	public String[] getXsltParamHeaders() {
-		return xsltParamHeaders;
-	}
-
-	public void setXsltParamHeaders(String[] xsltParamHeaders) {
-		this.xsltParamHeaders = xsltParamHeaders;
-	}
-	public String getComponentType(){
-		return "xml:xslt-transformer";
-	}
 }

spring-integration-xml/src/main/java/org/springframework/integration/xml/xpath/XPathEvaluationType.java

@@ -1,33 +1,62 @@
+/*
+ * 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.xml.xpath;
 
-import org.springframework.xml.xpath.XPathExpression;
 import org.w3c.dom.Node;
 
+import org.springframework.xml.xpath.XPathExpression;
 
 /**
- * Enumeration of different types o XPath evaluation used to indicate the type of evaluation that should be carried out
- * using a provided XPath expression
+ * Enumeration of different types of XPath evaluation used to indicate the type
+ * of evaluation that should be carried out using a provided XPath expression.
  */
 public enum XPathEvaluationType {
 
-    BOOLEAN_RESULT {public Object evaluateXPath(XPathExpression expression, Node node) {
-        return expression.evaluateAsBoolean(node);
-    }},
+	BOOLEAN_RESULT {
+		public Object evaluateXPath(XPathExpression expression, Node node) {
+			return expression.evaluateAsBoolean(node);
+		}
+	},
 
-    STRING_RESULT {public Object evaluateXPath(XPathExpression expression, Node node) {
-        return expression.evaluateAsString(node);
-    }},
-    NUMBER_RESULT {public Object evaluateXPath(XPathExpression expression, Node node) {
-        return expression.evaluateAsNumber(node);
-    }},
+	STRING_RESULT {
+		public Object evaluateXPath(XPathExpression expression, Node node) {
+			return expression.evaluateAsString(node);
+		}
+	},
 
-    NODE_RESULT {public Object evaluateXPath(XPathExpression expression, Node node) {
-        return expression.evaluateAsNode(node);
-    }},
-    NODE_LIST_RESULT {public Object evaluateXPath(XPathExpression expression, Node node) {
-        return expression.evaluateAsNodeList(node);
-    }};
+	NUMBER_RESULT {
+		public Object evaluateXPath(XPathExpression expression, Node node) {
+			return expression.evaluateAsNumber(node);
+		}
+	},
 
-    public abstract Object evaluateXPath(XPathExpression expression, Node node);
+	NODE_RESULT {
+		public Object evaluateXPath(XPathExpression expression, Node node) {
+			return expression.evaluateAsNode(node);
+		}
+	},
+
+	NODE_LIST_RESULT {
+		public Object evaluateXPath(XPathExpression expression, Node node) {
+			return expression.evaluateAsNodeList(node);
+		}
+	};
+
+
+	public abstract Object evaluateXPath(XPathExpression expression, Node node);
 
 }