jaxb/plugins/org.eclipse.jpt.jaxb.eclipselink.core/src/org/eclipse/jpt/jaxb/eclipselink/core/internal/context/xpath/java/XPath.java - dali/webtools.dali - Git at Google

 /*******************************************************************************
  *  Copyright (c) 2012  Oracle. All rights reserved.
  *  This program and the accompanying materials are made available under the
  *  terms of the Eclipse Public License v1.0, which accompanies this distribution
  *  and is available at http://www.eclipse.org/legal/epl-v10.html
  *
  *  Contributors:
  *  	Oracle - initial API and implementation
  *******************************************************************************/
 package org.eclipse.jpt.jaxb.eclipselink.core.internal.context.xpath.java;

 import java.util.List;
 import java.util.Vector;
 import org.eclipse.jpt.common.core.internal.utility.SimpleTextRange;
 import org.eclipse.jpt.common.core.utility.TextRange;
 import org.eclipse.jpt.common.utility.Filter;
 import org.eclipse.jpt.common.utility.internal.ArrayTools;
 import org.eclipse.jpt.common.utility.internal.CollectionTools;
 import org.eclipse.jpt.common.utility.internal.StringTools;
 import org.eclipse.jpt.common.utility.internal.iterables.CompositeIterable;
 import org.eclipse.jpt.common.utility.internal.iterables.EmptyIterable;
 import org.eclipse.jpt.common.utility.internal.iterables.FilteringIterable;
 import org.eclipse.jpt.common.utility.internal.iterables.SingleElementIterable;
 import org.eclipse.jpt.common.utility.internal.iterables.TransformationIterable;
 import org.eclipse.jpt.jaxb.core.JaxbNode;
 import org.eclipse.jpt.jaxb.core.context.JaxbPackage;
 import org.eclipse.jpt.jaxb.core.context.JaxbPackageInfo;
 import org.eclipse.jpt.jaxb.core.context.XmlNs;
 import org.eclipse.jpt.jaxb.core.context.XmlSchema;
 import org.eclipse.jpt.jaxb.core.xsd.XsdAttributeUse;
 import org.eclipse.jpt.jaxb.core.xsd.XsdElementDeclaration;
 import org.eclipse.jpt.jaxb.core.xsd.XsdTypeDefinition;
 import org.eclipse.jpt.jaxb.eclipselink.core.internal.validation.ELJaxbValidationMessageBuilder;
 import org.eclipse.jpt.jaxb.eclipselink.core.internal.validation.ELJaxbValidationMessages;
 import org.eclipse.wst.validation.internal.provisional.core.IMessage;


 public class XPath {

 	public static String DELIM = "/";

 	public static String ATT_PREFIX = "@";

 	public static String TEXT = "text()";

 	public static String SELF = ".";

 	public static String COLON = ":";

 	public static char OPEN_BRACKET = '[';

 	public static char CLOSE_BRACKET = ']';


 	public static String attributeXPath(String prefix, String localName) {
 		if (prefix == null) {
 			return StringTools.concatenate(ATT_PREFIX, localName);
 		}
 		return StringTools.concatenate(ATT_PREFIX, prefix, COLON, localName);
 	}

 	public static String elementXPath(String prefix, String localName) {
 		if (prefix == null) {
 			return localName;
 		}
 		return StringTools.concatenate(prefix, COLON, localName);
 	}


 	List<Step> steps;


 	XPath(String xpathString) {
 		this.steps = new Vector<Step>();
 		parse(xpathString);
 	}


 	protected int getIndex(Step step) {
 		return this.steps.indexOf(step);
 	}

 	protected Step getFirstStep() {
 		if (this.steps.size() > 0) {
 			return this.steps.get(0);
 		}
 		return null;
 	}

 	protected Step getNextStep(Step step) {
 		int nextIndex = getIndex(step) + 1;
 		if (this.steps.size() > nextIndex) {
 			return this.steps.get(nextIndex);
 		}
 		return null;
 	}

 	protected void parse(String xpath) {
 		for (String segment : xpath.split(DELIM, -1)) {
 			this.steps.add(createStep(segment));
 		}
 	}

 	protected Step createStep(String stepValue) {
 		if (TEXT.equals(stepValue)) {
 			return new TextStep();
 		}
 		else if (SELF.equals(stepValue)) {
 			return new SelfStep();
 		}
 		else if (stepValue.startsWith(ATT_PREFIX)) {
 			return tryCreateAttributeStep(stepValue);
 		}
 		else {
 			return tryCreateElementStep(stepValue);
 		}
 	}

 	protected Step tryCreateAttributeStep(String stepValue) {
 		// must start with "@" - already tested that
 		try {
 			String attributeStepValue = stepValue.substring(1);
 			String[] stepParts = parseStepParts(attributeStepValue);
 			return new AttributeStep(stepParts[0], stepParts[1], ArrayTools.subArray(stepParts, 2, stepParts.length));
 		}
 		catch (IllegalArgumentException ife) {
 			return new InvalidStep(stepValue);
 		}
 	}

 	protected Step tryCreateElementStep(String stepValue) {
 		try {
 			String[] stepParts = parseStepParts(stepValue);
 			return new ElementStep(stepParts[0], stepParts[1], ArrayTools.subArray(stepParts, 2, stepParts.length));
 		}
 		catch (IllegalArgumentException ife) {
 			return new InvalidStep(stepValue);
 		}
 	}

 	protected String[] parseStepParts(String stepValue) {
 		String[] predicate = new String[0];
 		int predicateStart = stepValue.lastIndexOf(OPEN_BRACKET);
 		while (predicateStart >= 0) {
 			int predicateEnd = stepValue.lastIndexOf(CLOSE_BRACKET);
 			if (predicateEnd <= predicateStart || predicateEnd != stepValue.length() - 1) {
 				throw new IllegalArgumentException();
 			}
 			predicate = ArrayTools.add(predicate, 0, stepValue.substring(predicateStart +1, predicateEnd));
 			stepValue = stepValue.substring(0, predicateStart);
 			predicateStart = stepValue.lastIndexOf(OPEN_BRACKET);
 		}

 		String nsPrefix = null;
 		int colon = stepValue.indexOf(COLON);
 		if (colon > 0) {
 			if (stepValue.indexOf(COLON, colon + 1) != -1) {
 				throw new IllegalArgumentException();
 			}
 			nsPrefix = stepValue.substring(0, colon);
 			stepValue = stepValue.substring(colon +1);
 		}

 		if (StringTools.stringIsEmpty(stepValue)
 				|| stepValue.indexOf(COLON) >= 0
 				|| stepValue.indexOf(OPEN_BRACKET) >= 0
 				|| stepValue.indexOf(CLOSE_BRACKET) >= 0
 				|| stepValue.indexOf(' ') >= 0) {
 			throw new IllegalArgumentException();
 		}

 		String[] result = ArrayTools.add(new String[0], nsPrefix);
 		result = ArrayTools.add(result, stepValue);
 		result = ArrayTools.addAll(result, predicate);
 		return result;
 	}


 	// ***** content assist *****

 	public Iterable<String> getCompletionProposals(
 			Context context, XsdTypeDefinition xsdType, int pos, Filter<String> filter) {

 		return getFirstStep().getCompletionProposals(context, xsdType, StringTools.EMPTY_STRING, pos, filter);
 	}


 	// ***** validation *****

 	public void validate(Context context, XsdTypeDefinition xsdType, List<IMessage> messages) {
 		getFirstStep().validate(context, xsdType, messages);
 	}

 	protected TextRange buildTextRange(Context context, Step step) {
 		TextRange entireTextRange = context.getTextRange();
 		int start = 0;
 		for (Step each : this.steps) {
 			int length = each.getValue().length() + 2;  // include leading/trailing " or /
 			if (each == step) {
 				return new SimpleTextRange(entireTextRange.getOffset() + start, length, entireTextRange.getLineNumber());
 			}
 			else {
 				start += length - 1; // only include leading " or /
 			}
 		}
 		throw new IllegalArgumentException("Step must be in list of this XPath's steps.");
 	}


 	protected class AttributeStep
 			extends NamedComponentStep {

 		protected AttributeStep(String nsPrefix, String localName, String[] predicates) {
 			super(nsPrefix, localName, predicates);
 		}


 		@Override
 		protected String getValue() {
 			return ATT_PREFIX + super.getValue();
 		}

 		@Override
 		protected XsdTypeDefinition resolveNextType(Context context, XsdTypeDefinition previousType) {
 			String namespace = resolveNamespace(context);
 			if (namespace == null) {
 				return null;
 			}

 			XsdAttributeUse xsdAttribute = previousType.getAttribute(namespace, this.localName);
 			return (xsdAttribute == null) ? null : xsdAttribute.getAttributeDeclaration().getType();
 		}

 		@Override
 		protected void validate(
 				Context context, XsdTypeDefinition previousType, List<IMessage> messages) {

 			if (getNextStep() != null) {
 				messages.add(
 						ELJaxbValidationMessageBuilder.buildMessage(
 								IMessage.HIGH_SEVERITY,
 								ELJaxbValidationMessages.XPATH__ATTRIBUTE_SEGMENT_MUST_BE_LAST_SEGMENT,
 								context.getContextObject(),
 								getTextRange(context)));
 				return;
 			}

 			super.validate(context, previousType, messages);
 		}

 		@Override
 		protected XsdTypeDefinition validateLocalName(
 				Context context, XsdTypeDefinition previousType, String namespace, List<IMessage> messages) {

 			XsdAttributeUse xsdAttribute= previousType.getAttribute(namespace, this.localName);
 			if (xsdAttribute == null) {
 				messages.add(
 						ELJaxbValidationMessageBuilder.buildMessage(
 								IMessage.HIGH_SEVERITY,
 								ELJaxbValidationMessages.XPATH__UNRESOLVED_ATTRIBUTE,
 								new String[] { namespace, this.localName },
 								context.getContextObject(),
 								getTextRange(context)));
 				return null;
 			}
 			else {
 				return xsdAttribute.getAttributeDeclaration().getType();
 			}
 		}

 //		@Override
 //		protected TextRange buildNamespacePrefixTextRange(CompilationUnit astRoot) {
 //			// assume nsPrefix != null
 //			TextRange stepTextRange = ELJavaXmlPath.this.buildTextRange(this, astRoot);
 //			return new SimpleTextRange(stepTextRange.getOffset() + 1, this.nsPrefix.length(), stepTextRange.getLineNumber());
 //		}
 	}

 	protected class ElementStep
 			extends NamedComponentStep {

 		protected ElementStep(String nsPrefix, String localName, String[] predicates) {
 			super(nsPrefix, localName, predicates);
 		}


 		@Override
 		protected XsdTypeDefinition
 				resolveNextType(Context context, XsdTypeDefinition previousType) {

 			String namespace = resolveNamespace(context);
 			if (namespace == null) {
 				return null;
 			}

 			XsdElementDeclaration xsdElement = previousType.getElement(namespace, this.localName);
 			return (xsdElement == null) ? null : xsdElement.getType();
 		}


 		@Override
 		protected XsdTypeDefinition validateLocalName(
 				Context context, XsdTypeDefinition previousType, String namespace, List<IMessage> messages) {

 			XsdElementDeclaration xsdElement = previousType.getElement(namespace, this.localName);
 			if (xsdElement == null) {
 				messages.add(
 						ELJaxbValidationMessageBuilder.buildMessage(
 								IMessage.HIGH_SEVERITY,
 								ELJaxbValidationMessages.XPATH__UNRESOLVED_ELEMENT,
 								new String[] { namespace, this.localName },
 								context.getContextObject(),
 								getTextRange(context)));
 				return null;
 			}
 			else {
 				return xsdElement.getType();
 			}
 		}

 //		@Override
 //		protected TextRange buildNamespacePrefixTextRange(CompilationUnit astRoot) {
 //			// assume nsPrefix != null
 //			TextRange stepTextRange = ELJavaXmlPath.this.buildTextRange(this, astRoot);
 //			return new SimpleTextRange(stepTextRange.getOffset(), this.nsPrefix.length(), stepTextRange.getLineNumber());
 //		}
 	}

 	protected class InvalidStep
 			extends Step {

 		protected String value;

 		protected InvalidStep(String value) {
 			super();
 			this.value = value;
 		}

 		@Override
 		protected String getValue() {
 			return this.value;
 		}

 		@Override
 		protected XsdTypeDefinition
 				resolveNextType(Context context, XsdTypeDefinition previousType) {

 			return null;
 		}

 		@Override
 		protected void validate(
 				Context context, XsdTypeDefinition previousType, List<IMessage> messages) {

 			messages. add(ELJaxbValidationMessageBuilder.buildMessage(
 							IMessage.HIGH_SEVERITY,
 							ELJaxbValidationMessages.XPATH__INVALID_FORM_ILLEGAL_SEGMENT,
 							new String[] { getValue() },
 							context.getContextObject(),
 							getTextRange(context)));
 			return;
 		}
 	}

 	protected abstract class NamedComponentStep
 			extends Step {

 		protected String nsPrefix;

 		protected String localName;

 		protected List<String> predicates;


 		protected NamedComponentStep(String nsPrefix, String localName, String[] predicates) {
 			super();
 			this.nsPrefix = nsPrefix;
 			this.localName = localName;
 			this.predicates = new Vector<String>();
 			CollectionTools.addAll(this.predicates, predicates);
 		}

 		@Override
 		protected String getValue() {
 			StringBuffer sb = new StringBuffer();
 			if (this.nsPrefix != null) {
 				sb.append(nsPrefix);
 				sb.append(COLON);
 			}
 			sb.append(this.localName);
 			for (String predicate : this.predicates) {
 				sb.append(OPEN_BRACKET);
 				sb.append(predicate);
 				sb.append(CLOSE_BRACKET);
 			}
 			return sb.toString();
 		}

 		protected String resolveNamespace(Context context) {
 			JaxbPackage pkg = context.getJaxbPackage();
 			if (this.nsPrefix == null) {
 				return "";
 			}
 			else {
 				JaxbPackageInfo pkgInfo = pkg.getPackageInfo();
 				return (pkgInfo == null) ? null : pkgInfo.getNamespaceForPrefix(this.nsPrefix);
 			}
 		}

 		@Override
 		protected void validate(
 				Context context, XsdTypeDefinition previousType, List<IMessage> messages) {

 			String namespace = resolveNamespace(context);

 			if (namespace == null) {
 				messages.add(
 						ELJaxbValidationMessageBuilder.buildMessage(
 								IMessage.HIGH_SEVERITY,
 								ELJaxbValidationMessages.XPATH__INVALID_NS_PREFIX,
 								new String[] { this.nsPrefix },
 								context.getContextObject(),
 								getTextRange(context)));
 			}

 			XsdTypeDefinition nextType = (previousType == null) ? null : validateLocalName(context, previousType, namespace, messages);
 			if (nextType != null) {
 				Step nextStep = getNextStep();
 				if (nextStep != null) {
 					nextStep.validate(context, nextType, messages);
 				}
 			}
 		}

 		protected abstract XsdTypeDefinition validateLocalName(
 				Context context, XsdTypeDefinition previousType, String namespace, List<IMessage> messages);

 //		protected abstract TextRange buildNamespacePrefixTextRange(CompilationUnit astRoot);
 	}

 	protected class SelfStep
 			extends Step {

 		protected SelfStep() {
 			super();
 		}


 		@Override
 		protected String getValue() {
 			return SELF;
 		}

 		@Override
 		protected XsdTypeDefinition
 				resolveNextType(Context context, XsdTypeDefinition previousType) {

 			return previousType;
 		}

 		@Override
 		protected void validate(
 				Context context, XsdTypeDefinition previousType, List<IMessage> messages) {

 			if (getIndex() != 0) {
 				messages.add(
 						ELJaxbValidationMessageBuilder.buildMessage(
 								IMessage.HIGH_SEVERITY,
 								ELJaxbValidationMessages.XPATH__SELF_SEGMENT_MUST_BE_FIRST_SEGMENT,
 								context.getContextObject(),
 								getTextRange(context)));
 				return;
 			}

 			if (getNextStep() != null) {
 				getNextStep().validate(context, previousType, messages);
 			}
 		}
 	}

 	protected abstract class Step {

 		protected int getIndex() {
 			return XPath.this.getIndex(this);
 		}

 		protected Step getNextStep() {
 			return XPath.this.getNextStep(this);
 		}

 		protected abstract String getValue();

 		protected abstract XsdTypeDefinition resolveNextType(Context context, XsdTypeDefinition previousType);

 		protected Iterable<String> getCompletionProposals(
 				Context context, XsdTypeDefinition previousType,
 				final String prefix, int pos, Filter<String> filter) {

 			if (getTextRange(context).includes(pos) || getNextStep() == null) {
 				return StringTools.convertToJavaStringLiterals(
 						new FilteringIterable<String>(
 								new TransformationIterable<String, String>(
 										new CompositeIterable<String>(
 												getTextProposals(context, previousType),
 												getAttributeProposals(context, previousType),
 												getElementProposals(context, previousType))) {
 									@Override
 									protected String transform(String o) {
 										return StringTools.concatenate(prefix, o);
 									}
 								},
 								filter));
 			}

 			Step nextStep = getNextStep();
 			XsdTypeDefinition nextType = resolveNextType(context, previousType);
 			if (nextStep != null && nextType != null) {
 				return nextStep.getCompletionProposals(context, nextType, prefix + getValue() + DELIM, pos, filter);
 			}

 			return new SingleElementIterable(TEXT);
 		}

 		protected Iterable<String> getTextProposals(Context context, final XsdTypeDefinition xsdType) {
 			return (xsdType.hasTextContent()) ? new SingleElementIterable(TEXT) : EmptyIterable.instance();
 		}

 		protected Iterable<String> getAttributeProposals(Context context, final XsdTypeDefinition xsdType) {
 			return new CompositeIterable<String>(
 					new CompositeIterable<String>(
 							new TransformationIterable<XmlNs, Iterable<String>>(getXmlNsInfos(context)) {
 								@Override
 								protected Iterable<String> transform(final XmlNs xmlns) {
 									return new TransformationIterable<String, String>(xsdType.getAttributeNames(xmlns.getNamespaceURI())) {
 										@Override
 										protected String transform(String o) {
 											return XPath.attributeXPath(xmlns.getPrefix(), o);
 										}
 									};
 								}
 							}),
 					new TransformationIterable<String, String>(xsdType.getAttributeNames("")) {
 						@Override
 						protected String transform(String o) {
 							return XPath.attributeXPath(null, o);
 						}
 					});
 		}

 		protected Iterable<String> getElementProposals(Context context, final XsdTypeDefinition xsdType) {
 			return new CompositeIterable<String>(
 					new CompositeIterable<String>(
 							new TransformationIterable<XmlNs, Iterable<String>>(getXmlNsInfos(context)) {
 								@Override
 								protected Iterable<String> transform(final XmlNs xmlns) {
 									return new TransformationIterable<String, String>(xsdType.getElementNames(xmlns.getNamespaceURI(), false)) {
 										@Override
 										protected String transform(String o) {
 											return XPath.elementXPath(xmlns.getPrefix(), o);
 										}
 									};
 								}
 							}),
 					xsdType.getElementNames("", false));
 		}

 		protected Iterable<XmlNs> getXmlNsInfos(Context context) {
 			JaxbPackageInfo pkgInfo = context.getJaxbPackage().getPackageInfo();
 			XmlSchema xmlSchema = (pkgInfo == null) ? null : pkgInfo.getXmlSchema();
 			return (xmlSchema == null) ? EmptyIterable.<XmlNs>instance() : xmlSchema.getXmlNsPrefixes();
 		}

 		protected void validate(Context context, XsdTypeDefinition previousType, List<IMessage> messages) {
 			// no op
 		}

 		protected TextRange getTextRange(Context context) {
 			return XPath.this.buildTextRange(context, this);
 		}
 	}

 	protected class TextStep
 			extends Step {

 		protected TextStep() {
 			super();
 		}

 		@Override
 		protected String getValue() {
 			return TEXT;
 		}

 		@Override
 		protected XsdTypeDefinition
 				resolveNextType(Context context, XsdTypeDefinition previousType) {

 			return previousType;
 		}

 		@Override
 		protected void validate(
 				Context context, XsdTypeDefinition previousType, List<IMessage> messages) {

 			if (getNextStep() != null) {
 				messages.add(
 						ELJaxbValidationMessageBuilder.buildMessage(
 								IMessage.HIGH_SEVERITY,
 								ELJaxbValidationMessages.XPATH__TEXT_SEGMENT_MUST_BE_LAST_SEGMENT,
 								context.getContextObject(),
 								getTextRange(context)));
 			}
 		}
 	}


 	public interface Context {

 		JaxbNode getContextObject();

 		JaxbPackage getJaxbPackage();

 		TextRange getTextRange();
 	}
 }
	/*******************************************************************************
	* Copyright (c) 2012 Oracle. All rights reserved.
	* This program and the accompanying materials are made available under the
	* terms of the Eclipse Public License v1.0, which accompanies this distribution
	* and is available at http://www.eclipse.org/legal/epl-v10.html
	*
	* Contributors:
	* Oracle - initial API and implementation
	*******************************************************************************/
	package org.eclipse.jpt.jaxb.eclipselink.core.internal.context.xpath.java;

	import java.util.List;
	import java.util.Vector;
	import org.eclipse.jpt.common.core.internal.utility.SimpleTextRange;
	import org.eclipse.jpt.common.core.utility.TextRange;
	import org.eclipse.jpt.common.utility.Filter;
	import org.eclipse.jpt.common.utility.internal.ArrayTools;
	import org.eclipse.jpt.common.utility.internal.CollectionTools;
	import org.eclipse.jpt.common.utility.internal.StringTools;
	import org.eclipse.jpt.common.utility.internal.iterables.CompositeIterable;
	import org.eclipse.jpt.common.utility.internal.iterables.EmptyIterable;
	import org.eclipse.jpt.common.utility.internal.iterables.FilteringIterable;
	import org.eclipse.jpt.common.utility.internal.iterables.SingleElementIterable;
	import org.eclipse.jpt.common.utility.internal.iterables.TransformationIterable;
	import org.eclipse.jpt.jaxb.core.JaxbNode;
	import org.eclipse.jpt.jaxb.core.context.JaxbPackage;
	import org.eclipse.jpt.jaxb.core.context.JaxbPackageInfo;
	import org.eclipse.jpt.jaxb.core.context.XmlNs;
	import org.eclipse.jpt.jaxb.core.context.XmlSchema;
	import org.eclipse.jpt.jaxb.core.xsd.XsdAttributeUse;
	import org.eclipse.jpt.jaxb.core.xsd.XsdElementDeclaration;
	import org.eclipse.jpt.jaxb.core.xsd.XsdTypeDefinition;
	import org.eclipse.jpt.jaxb.eclipselink.core.internal.validation.ELJaxbValidationMessageBuilder;
	import org.eclipse.jpt.jaxb.eclipselink.core.internal.validation.ELJaxbValidationMessages;
	import org.eclipse.wst.validation.internal.provisional.core.IMessage;


	public class XPath {

	public static String DELIM = "/";

	public static String ATT_PREFIX = "@";

	public static String TEXT = "text()";

	public static String SELF = ".";

	public static String COLON = ":";

	public static char OPEN_BRACKET = '[';

	public static char CLOSE_BRACKET = ']';


	public static String attributeXPath(String prefix, String localName) {
	if (prefix == null) {
	return StringTools.concatenate(ATT_PREFIX, localName);
	}
	return StringTools.concatenate(ATT_PREFIX, prefix, COLON, localName);
	}

	public static String elementXPath(String prefix, String localName) {
	if (prefix == null) {
	return localName;
	}
	return StringTools.concatenate(prefix, COLON, localName);
	}


	List<Step> steps;


	XPath(String xpathString) {
	this.steps = new Vector<Step>();
	parse(xpathString);
	}


	protected int getIndex(Step step) {
	return this.steps.indexOf(step);
	}

	protected Step getFirstStep() {
	if (this.steps.size() > 0) {
	return this.steps.get(0);
	}
	return null;
	}

	protected Step getNextStep(Step step) {
	int nextIndex = getIndex(step) + 1;
	if (this.steps.size() > nextIndex) {
	return this.steps.get(nextIndex);
	}
	return null;
	}

	protected void parse(String xpath) {
	for (String segment : xpath.split(DELIM, -1)) {
	this.steps.add(createStep(segment));
	}
	}

	protected Step createStep(String stepValue) {
	if (TEXT.equals(stepValue)) {
	return new TextStep();
	}
	else if (SELF.equals(stepValue)) {
	return new SelfStep();
	}
	else if (stepValue.startsWith(ATT_PREFIX)) {
	return tryCreateAttributeStep(stepValue);
	}
	else {
	return tryCreateElementStep(stepValue);
	}
	}

	protected Step tryCreateAttributeStep(String stepValue) {
	// must start with "@" - already tested that
	try {
	String attributeStepValue = stepValue.substring(1);
	String[] stepParts = parseStepParts(attributeStepValue);
	return new AttributeStep(stepParts[0], stepParts[1], ArrayTools.subArray(stepParts, 2, stepParts.length));
	}
	catch (IllegalArgumentException ife) {
	return new InvalidStep(stepValue);
	}
	}

	protected Step tryCreateElementStep(String stepValue) {
	try {
	String[] stepParts = parseStepParts(stepValue);
	return new ElementStep(stepParts[0], stepParts[1], ArrayTools.subArray(stepParts, 2, stepParts.length));
	}
	catch (IllegalArgumentException ife) {
	return new InvalidStep(stepValue);
	}
	}

	protected String[] parseStepParts(String stepValue) {
	String[] predicate = new String[0];
	int predicateStart = stepValue.lastIndexOf(OPEN_BRACKET);
	while (predicateStart >= 0) {
	int predicateEnd = stepValue.lastIndexOf(CLOSE_BRACKET);
	if (predicateEnd <= predicateStart \|\| predicateEnd != stepValue.length() - 1) {
	throw new IllegalArgumentException();
	}
	predicate = ArrayTools.add(predicate, 0, stepValue.substring(predicateStart +1, predicateEnd));
	stepValue = stepValue.substring(0, predicateStart);
	predicateStart = stepValue.lastIndexOf(OPEN_BRACKET);
	}

	String nsPrefix = null;
	int colon = stepValue.indexOf(COLON);
	if (colon > 0) {
	if (stepValue.indexOf(COLON, colon + 1) != -1) {
	throw new IllegalArgumentException();
	}
	nsPrefix = stepValue.substring(0, colon);
	stepValue = stepValue.substring(colon +1);
	}

	if (StringTools.stringIsEmpty(stepValue)
	\|\| stepValue.indexOf(COLON) >= 0
	\|\| stepValue.indexOf(OPEN_BRACKET) >= 0
	\|\| stepValue.indexOf(CLOSE_BRACKET) >= 0
	\|\| stepValue.indexOf(' ') >= 0) {
	throw new IllegalArgumentException();
	}

	String[] result = ArrayTools.add(new String[0], nsPrefix);
	result = ArrayTools.add(result, stepValue);
	result = ArrayTools.addAll(result, predicate);
	return result;
	}


	// *** content assist ***

	public Iterable<String> getCompletionProposals(
	Context context, XsdTypeDefinition xsdType, int pos, Filter<String> filter) {

	return getFirstStep().getCompletionProposals(context, xsdType, StringTools.EMPTY_STRING, pos, filter);
	}


	// *** validation ***

	public void validate(Context context, XsdTypeDefinition xsdType, List<IMessage> messages) {
	getFirstStep().validate(context, xsdType, messages);
	}

	protected TextRange buildTextRange(Context context, Step step) {
	TextRange entireTextRange = context.getTextRange();
	int start = 0;
	for (Step each : this.steps) {
	int length = each.getValue().length() + 2; // include leading/trailing " or /
	if (each == step) {
	return new SimpleTextRange(entireTextRange.getOffset() + start, length, entireTextRange.getLineNumber());
	}
	else {
	start += length - 1; // only include leading " or /
	}
	}
	throw new IllegalArgumentException("Step must be in list of this XPath's steps.");
	}


	protected class AttributeStep
	extends NamedComponentStep {

	protected AttributeStep(String nsPrefix, String localName, String[] predicates) {
	super(nsPrefix, localName, predicates);
	}


	@Override
	protected String getValue() {
	return ATT_PREFIX + super.getValue();
	}

	@Override
	protected XsdTypeDefinition resolveNextType(Context context, XsdTypeDefinition previousType) {
	String namespace = resolveNamespace(context);
	if (namespace == null) {
	return null;
	}

	XsdAttributeUse xsdAttribute = previousType.getAttribute(namespace, this.localName);
	return (xsdAttribute == null) ? null : xsdAttribute.getAttributeDeclaration().getType();
	}

	@Override
	protected void validate(
	Context context, XsdTypeDefinition previousType, List<IMessage> messages) {

	if (getNextStep() != null) {
	messages.add(
	ELJaxbValidationMessageBuilder.buildMessage(
	IMessage.HIGH_SEVERITY,
	ELJaxbValidationMessages.XPATH__ATTRIBUTE_SEGMENT_MUST_BE_LAST_SEGMENT,
	context.getContextObject(),
	getTextRange(context)));
	return;
	}

	super.validate(context, previousType, messages);
	}

	@Override
	protected XsdTypeDefinition validateLocalName(
	Context context, XsdTypeDefinition previousType, String namespace, List<IMessage> messages) {

	XsdAttributeUse xsdAttribute= previousType.getAttribute(namespace, this.localName);
	if (xsdAttribute == null) {
	messages.add(
	ELJaxbValidationMessageBuilder.buildMessage(
	IMessage.HIGH_SEVERITY,
	ELJaxbValidationMessages.XPATH__UNRESOLVED_ATTRIBUTE,
	new String[] { namespace, this.localName },
	context.getContextObject(),
	getTextRange(context)));
	return null;
	}
	else {
	return xsdAttribute.getAttributeDeclaration().getType();
	}
	}

	// @Override
	// protected TextRange buildNamespacePrefixTextRange(CompilationUnit astRoot) {
	// // assume nsPrefix != null
	// TextRange stepTextRange = ELJavaXmlPath.this.buildTextRange(this, astRoot);
	// return new SimpleTextRange(stepTextRange.getOffset() + 1, this.nsPrefix.length(), stepTextRange.getLineNumber());
	// }
	}

	protected class ElementStep
	extends NamedComponentStep {

	protected ElementStep(String nsPrefix, String localName, String[] predicates) {
	super(nsPrefix, localName, predicates);
	}


	@Override
	protected XsdTypeDefinition
	resolveNextType(Context context, XsdTypeDefinition previousType) {

	String namespace = resolveNamespace(context);
	if (namespace == null) {
	return null;
	}

	XsdElementDeclaration xsdElement = previousType.getElement(namespace, this.localName);
	return (xsdElement == null) ? null : xsdElement.getType();
	}


	@Override
	protected XsdTypeDefinition validateLocalName(
	Context context, XsdTypeDefinition previousType, String namespace, List<IMessage> messages) {

	XsdElementDeclaration xsdElement = previousType.getElement(namespace, this.localName);
	if (xsdElement == null) {
	messages.add(
	ELJaxbValidationMessageBuilder.buildMessage(
	IMessage.HIGH_SEVERITY,
	ELJaxbValidationMessages.XPATH__UNRESOLVED_ELEMENT,
	new String[] { namespace, this.localName },
	context.getContextObject(),
	getTextRange(context)));
	return null;
	}
	else {
	return xsdElement.getType();
	}
	}

	// @Override
	// protected TextRange buildNamespacePrefixTextRange(CompilationUnit astRoot) {
	// // assume nsPrefix != null
	// TextRange stepTextRange = ELJavaXmlPath.this.buildTextRange(this, astRoot);
	// return new SimpleTextRange(stepTextRange.getOffset(), this.nsPrefix.length(), stepTextRange.getLineNumber());
	// }
	}

	protected class InvalidStep
	extends Step {

	protected String value;

	protected InvalidStep(String value) {
	super();
	this.value = value;
	}

	@Override
	protected String getValue() {
	return this.value;
	}

	@Override
	protected XsdTypeDefinition
	resolveNextType(Context context, XsdTypeDefinition previousType) {

	return null;
	}

	@Override
	protected void validate(
	Context context, XsdTypeDefinition previousType, List<IMessage> messages) {

	messages. add(ELJaxbValidationMessageBuilder.buildMessage(
	IMessage.HIGH_SEVERITY,
	ELJaxbValidationMessages.XPATH__INVALID_FORM_ILLEGAL_SEGMENT,
	new String[] { getValue() },
	context.getContextObject(),
	getTextRange(context)));
	return;
	}
	}

	protected abstract class NamedComponentStep
	extends Step {

	protected String nsPrefix;

	protected String localName;

	protected List<String> predicates;


	protected NamedComponentStep(String nsPrefix, String localName, String[] predicates) {
	super();
	this.nsPrefix = nsPrefix;
	this.localName = localName;
	this.predicates = new Vector<String>();
	CollectionTools.addAll(this.predicates, predicates);
	}

	@Override
	protected String getValue() {
	StringBuffer sb = new StringBuffer();
	if (this.nsPrefix != null) {
	sb.append(nsPrefix);
	sb.append(COLON);
	}
	sb.append(this.localName);
	for (String predicate : this.predicates) {
	sb.append(OPEN_BRACKET);
	sb.append(predicate);
	sb.append(CLOSE_BRACKET);
	}
	return sb.toString();
	}

	protected String resolveNamespace(Context context) {
	JaxbPackage pkg = context.getJaxbPackage();
	if (this.nsPrefix == null) {
	return "";
	}
	else {
	JaxbPackageInfo pkgInfo = pkg.getPackageInfo();
	return (pkgInfo == null) ? null : pkgInfo.getNamespaceForPrefix(this.nsPrefix);
	}
	}

	@Override
	protected void validate(
	Context context, XsdTypeDefinition previousType, List<IMessage> messages) {

	String namespace = resolveNamespace(context);

	if (namespace == null) {
	messages.add(
	ELJaxbValidationMessageBuilder.buildMessage(
	IMessage.HIGH_SEVERITY,
	ELJaxbValidationMessages.XPATH__INVALID_NS_PREFIX,
	new String[] { this.nsPrefix },
	context.getContextObject(),
	getTextRange(context)));
	}

	XsdTypeDefinition nextType = (previousType == null) ? null : validateLocalName(context, previousType, namespace, messages);
	if (nextType != null) {
	Step nextStep = getNextStep();
	if (nextStep != null) {
	nextStep.validate(context, nextType, messages);
	}
	}
	}

	protected abstract XsdTypeDefinition validateLocalName(
	Context context, XsdTypeDefinition previousType, String namespace, List<IMessage> messages);

	// protected abstract TextRange buildNamespacePrefixTextRange(CompilationUnit astRoot);
	}

	protected class SelfStep
	extends Step {

	protected SelfStep() {
	super();
	}


	@Override
	protected String getValue() {
	return SELF;
	}

	@Override
	protected XsdTypeDefinition
	resolveNextType(Context context, XsdTypeDefinition previousType) {

	return previousType;
	}

	@Override
	protected void validate(
	Context context, XsdTypeDefinition previousType, List<IMessage> messages) {

	if (getIndex() != 0) {
	messages.add(
	ELJaxbValidationMessageBuilder.buildMessage(
	IMessage.HIGH_SEVERITY,
	ELJaxbValidationMessages.XPATH__SELF_SEGMENT_MUST_BE_FIRST_SEGMENT,
	context.getContextObject(),
	getTextRange(context)));
	return;
	}

	if (getNextStep() != null) {
	getNextStep().validate(context, previousType, messages);
	}
	}
	}

	protected abstract class Step {

	protected int getIndex() {
	return XPath.this.getIndex(this);
	}

	protected Step getNextStep() {
	return XPath.this.getNextStep(this);
	}

	protected abstract String getValue();

	protected abstract XsdTypeDefinition resolveNextType(Context context, XsdTypeDefinition previousType);

	protected Iterable<String> getCompletionProposals(
	Context context, XsdTypeDefinition previousType,
	final String prefix, int pos, Filter<String> filter) {

	if (getTextRange(context).includes(pos) \|\| getNextStep() == null) {
	return StringTools.convertToJavaStringLiterals(
	new FilteringIterable<String>(
	new TransformationIterable<String, String>(
	new CompositeIterable<String>(
	getTextProposals(context, previousType),
	getAttributeProposals(context, previousType),
	getElementProposals(context, previousType))) {
	@Override
	protected String transform(String o) {
	return StringTools.concatenate(prefix, o);
	}
	},
	filter));
	}

	Step nextStep = getNextStep();
	XsdTypeDefinition nextType = resolveNextType(context, previousType);
	if (nextStep != null && nextType != null) {
	return nextStep.getCompletionProposals(context, nextType, prefix + getValue() + DELIM, pos, filter);
	}

	return new SingleElementIterable(TEXT);
	}

	protected Iterable<String> getTextProposals(Context context, final XsdTypeDefinition xsdType) {
	return (xsdType.hasTextContent()) ? new SingleElementIterable(TEXT) : EmptyIterable.instance();
	}

	protected Iterable<String> getAttributeProposals(Context context, final XsdTypeDefinition xsdType) {
	return new CompositeIterable<String>(
	new CompositeIterable<String>(
	new TransformationIterable<XmlNs, Iterable<String>>(getXmlNsInfos(context)) {
	@Override
	protected Iterable<String> transform(final XmlNs xmlns) {
	return new TransformationIterable<String, String>(xsdType.getAttributeNames(xmlns.getNamespaceURI())) {
	@Override
	protected String transform(String o) {
	return XPath.attributeXPath(xmlns.getPrefix(), o);
	}
	};
	}
	}),
	new TransformationIterable<String, String>(xsdType.getAttributeNames("")) {
	@Override
	protected String transform(String o) {
	return XPath.attributeXPath(null, o);
	}
	});
	}

	protected Iterable<String> getElementProposals(Context context, final XsdTypeDefinition xsdType) {
	return new CompositeIterable<String>(
	new CompositeIterable<String>(
	new TransformationIterable<XmlNs, Iterable<String>>(getXmlNsInfos(context)) {
	@Override
	protected Iterable<String> transform(final XmlNs xmlns) {
	return new TransformationIterable<String, String>(xsdType.getElementNames(xmlns.getNamespaceURI(), false)) {
	@Override
	protected String transform(String o) {
	return XPath.elementXPath(xmlns.getPrefix(), o);
	}
	};
	}
	}),
	xsdType.getElementNames("", false));
	}

	protected Iterable<XmlNs> getXmlNsInfos(Context context) {
	JaxbPackageInfo pkgInfo = context.getJaxbPackage().getPackageInfo();
	XmlSchema xmlSchema = (pkgInfo == null) ? null : pkgInfo.getXmlSchema();
	return (xmlSchema == null) ? EmptyIterable.<XmlNs>instance() : xmlSchema.getXmlNsPrefixes();
	}

	protected void validate(Context context, XsdTypeDefinition previousType, List<IMessage> messages) {
	// no op
	}

	protected TextRange getTextRange(Context context) {
	return XPath.this.buildTextRange(context, this);
	}
	}

	protected class TextStep
	extends Step {

	protected TextStep() {
	super();
	}

	@Override
	protected String getValue() {
	return TEXT;
	}

	@Override
	protected XsdTypeDefinition
	resolveNextType(Context context, XsdTypeDefinition previousType) {

	return previousType;
	}

	@Override
	protected void validate(
	Context context, XsdTypeDefinition previousType, List<IMessage> messages) {

	if (getNextStep() != null) {
	messages.add(
	ELJaxbValidationMessageBuilder.buildMessage(
	IMessage.HIGH_SEVERITY,
	ELJaxbValidationMessages.XPATH__TEXT_SEGMENT_MUST_BE_LAST_SEGMENT,
	context.getContextObject(),
	getTextRange(context)));
	}
	}
	}


	public interface Context {

	JaxbNode getContextObject();

	JaxbPackage getJaxbPackage();

	TextRange getTextRange();
	}
	}