Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you 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.apache.ode.bpel.rtrep.v2.xquery10.runtime; import java.util.ArrayList; import java.util.Calendar; import java.util.Collections; import java.util.Date; import java.util.List; import java.util.Map; import java.util.Properties; import java.util.Set; import javax.xml.namespace.QName; import javax.xml.transform.TransformerFactory; import javax.xml.xpath.XPathConstants; import javax.xml.xquery.XQConnection; import javax.xml.xquery.XQConstants; import javax.xml.xquery.XQDataSource; import javax.xml.xquery.XQException; import javax.xml.xquery.XQItem; import javax.xml.xquery.XQItemType; import javax.xml.xquery.XQPreparedExpression; import javax.xml.xquery.XQResultSequence; import javax.xml.xquery.XQSequence; import javax.xml.xquery.XQSequenceType; import javax.xml.xquery.XQStaticContext; import net.sf.saxon.Configuration; import net.sf.saxon.om.Validation; import net.sf.saxon.trans.DynamicError; import net.sf.saxon.value.DurationValue; import net.sf.saxon.xqj.SaxonXQConnection; import net.sf.saxon.xqj.SaxonXQDataSource; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.apache.ode.bpel.common.FaultException; import org.apache.ode.bpel.rtrep.common.ConfigurationException; import org.apache.ode.bpel.rtrep.common.Constants; import org.apache.ode.bpel.rtrep.v2.EvaluationContext; import org.apache.ode.bpel.rtrep.v2.ExpressionLanguageRuntime; import org.apache.ode.bpel.rtrep.v2.OExpression; import org.apache.ode.bpel.rtrep.v2.xpath20.JaxpFunctionResolver; import org.apache.ode.bpel.rtrep.v2.xpath20.JaxpVariableResolver; import org.apache.ode.bpel.rtrep.v2.xquery10.OXQuery10ExpressionBPEL20; import org.apache.ode.utils.DOMUtils; import org.apache.ode.utils.ISO8601DateParser; import org.apache.ode.utils.NSContext; import org.apache.ode.utils.xsd.Duration; import org.apache.ode.utils.xsl.XslTransformHandler; import org.w3c.dom.Document; import org.w3c.dom.Element; import org.w3c.dom.Node; import org.w3c.dom.NodeList; import org.w3c.dom.Text; /** * XQuery 1.0 Expression Language run-time subsytem. Saxon implementation. */ @SuppressWarnings("deprecation") public class XQuery10ExpressionRuntime implements ExpressionLanguageRuntime { static final short NODE_TYPE = 1; static final short NODESET_TYPE = 2; static final short STRING_TYPE = 3; static final short BOOLEAN_TYPE = 4; static final short NUMBER_TYPE = 5; /** Class-level logger. */ private static final Log __log = LogFactory.getLog(XQuery10ExpressionRuntime.class); /** * Creates a new XQuery10ExpressionRuntime object. */ public XQuery10ExpressionRuntime() { } /** * Initialize XSL Transformer * * @param properties properties * * @throws ConfigurationException ConfigurationException */ public void initialize(Map properties) throws ConfigurationException { TransformerFactory trsf = new net.sf.saxon.TransformerFactoryImpl(); XslTransformHandler.getInstance().setTransformerFactory(trsf); } /** * * @see org.apache.ode.bpel.explang.ExpressionLanguageRuntime#evaluateAsString(org.apache.ode.bpel.o.OExpression, * org.apache.ode.bpel.explang.EvaluationContext) */ public String evaluateAsString(OExpression cexp, EvaluationContext ctx) throws FaultException { return (String) evaluate(cexp, ctx, XPathConstants.STRING); } /** * * @see org.apache.ode.bpel.explang.ExpressionLanguageRuntime#evaluateAsBoolean(org.apache.ode.bpel.o.OExpression, * org.apache.ode.bpel.explang.EvaluationContext) */ public boolean evaluateAsBoolean(OExpression cexp, EvaluationContext ctx) throws FaultException { return (Boolean) evaluate(cexp, ctx, XPathConstants.BOOLEAN); } /** * Evaluate expression and return a number * * @param cexp cexp * @param ctx ctx * * @return type * * @throws FaultException FaultException */ public Number evaluateAsNumber(OExpression cexp, EvaluationContext ctx) throws FaultException { return (Number) evaluate(cexp, ctx, XPathConstants.NUMBER); } /** * * @see org.apache.ode.bpel.explang.ExpressionLanguageRuntime#evaluate(org.apache.ode.bpel.o.OExpression, * org.apache.ode.bpel.explang.EvaluationContext) */ public List evaluate(OExpression cexp, EvaluationContext ctx) throws FaultException { List result; Object someRes = evaluate(cexp, ctx, XPathConstants.NODESET); if (someRes instanceof List) { result = (List) someRes; __log.debug("Returned list of size " + result.size()); if ((result.size() == 1) && !(result.get(0) instanceof Node)) { // Dealing with a Java class Object simpleType = result.get(0); // Dates get a separate treatment as we don't want to call toString on them String textVal; if (simpleType instanceof Date) { textVal = ISO8601DateParser.format((Date) simpleType); } else if (simpleType instanceof DurationValue) { textVal = ((DurationValue) simpleType).getStringValue(); } else { textVal = simpleType.toString(); } // Wrapping in a document Document d = DOMUtils.newDocument(); // Giving our node a parent just in case it's an LValue expression Element wrapper = d.createElement("wrapper"); Text text = d.createTextNode(textVal); wrapper.appendChild(text); d.appendChild(wrapper); result = Collections.singletonList(text); } } else if (someRes instanceof NodeList) { NodeList retVal = (NodeList) someRes; __log.debug("Returned node list of size " + retVal.getLength()); result = new ArrayList(retVal.getLength()); for (int m = 0; m < retVal.getLength(); ++m) { Node val = retVal.item(m); if (val.getNodeType() == Node.DOCUMENT_NODE) { val = ((Document) val).getDocumentElement(); } result.add(val); } } else { result = null; } return result; } /** * Evaluate expression and return a node * * @param cexp cexp * @param ctx ctx * * @return type * * @throws FaultException FaultException */ public Node evaluateNode(OExpression cexp, EvaluationContext ctx) throws FaultException { List retVal = evaluate(cexp, ctx); if (retVal.size() == 0) { throw new FaultException(cexp.getOwner().constants.qnSelectionFailure, "No results for expression: " + cexp); } if (retVal.size() > 1) { throw new FaultException(cexp.getOwner().constants.qnSelectionFailure, "Multiple results for expression: " + cexp); } return (Node) retVal.get(0); } /** * Evaluate expression and return a date * * @param cexp cexp * @param context context * * @return type * * @throws FaultException FaultException */ public Calendar evaluateAsDate(OExpression cexp, EvaluationContext context) throws FaultException { List literal = DOMUtils.toList(evaluate(cexp, context, XPathConstants.NODESET)); if (literal.size() == 0) { throw new FaultException(cexp.getOwner().constants.qnSelectionFailure, "No results for expression: " + cexp); } if (literal.size() > 1) { throw new FaultException(cexp.getOwner().constants.qnSelectionFailure, "Multiple results for expression: " + cexp); } Object date = literal.get(0); if (date instanceof Calendar) { return (Calendar) date; } if (date instanceof Date) { Calendar cal = Calendar.getInstance(); cal.setTime((Date) date); return cal; } if (date instanceof Element) { date = ((Element) date).getTextContent(); } try { return ISO8601DateParser.parseCal(date.toString()); } catch (Exception ex) { String errmsg = "Invalid date: " + literal; __log.error(errmsg, ex); throw new FaultException(cexp.getOwner().constants.qnInvalidExpressionValue, errmsg); } } /** * Evaluate expression and return duration * * @param cexp cexp * @param context context * * @return type * * @throws FaultException FaultException */ public Duration evaluateAsDuration(OExpression cexp, EvaluationContext context) throws FaultException { String literal = this.evaluateAsString(cexp, context); try { return new Duration(literal); } catch (Exception ex) { String errmsg = "Invalid duration: " + literal; __log.error(errmsg, ex); throw new FaultException(cexp.getOwner().constants.qnInvalidExpressionValue, errmsg); } } /** * Evaluate expression and return opaque type * * @param cexp cexp * @param ctx ctx * @param type type * * @return type * * @throws FaultException FaultException */ private Object evaluate(OExpression cexp, EvaluationContext ctx, QName type) throws FaultException { try { OXQuery10ExpressionBPEL20 oxquery10 = ((OXQuery10ExpressionBPEL20) cexp); XQDataSource xqds = new SaxonXQDataSource(); XQConnection xqconn = xqds.getConnection(); Configuration configuration = ((SaxonXQConnection) xqconn).getConfiguration(); configuration.setAllNodesUntyped(true); configuration.setHostLanguage(Configuration.XQUERY); XQStaticContext staticEnv = xqconn.getStaticContext(); NSContext nsContext = oxquery10.namespaceCtx; Set<String> prefixes = nsContext.getPrefixes(); for (String prefix : prefixes) { String uri = nsContext.getNamespaceURI(prefix); staticEnv.declareNamespace(prefix, uri); } configuration.setSchemaValidationMode(Validation.SKIP); xqconn.setStaticContext(staticEnv); // Prepare expression, for starters String xquery = oxquery10.xquery.replaceFirst(Constants.XQUERY_FUNCTION_HANDLER_COMPILER, Constants.XQUERY_FUNCTION_HANDLER_RUNTIME); XQPreparedExpression exp = xqconn.prepareExpression(xquery); JaxpFunctionResolver funcResolver = new JaxpFunctionResolver(ctx, oxquery10); JaxpVariableResolver variableResolver = new JaxpVariableResolver(ctx, oxquery10, configuration); // Bind external variables to runtime values for (QName variable : exp.getAllUnboundExternalVariables()) { // Evaluate referenced variable Object value = variableResolver.resolveVariable(variable); // Figure out type of variable XQSequenceType xqType = getItemType(xqconn, value); // Saxon doesn't like binding sequences to variables if (value instanceof Node) { // a node is a node-list, but the inverse isn't true. // so, if the value is truly a node, leave it alone. } else if (value instanceof NodeList) { // So extract the first item from the node list NodeList nodeList = (NodeList) value; ArrayList nodeArray = new ArrayList(); for (int i = 0; i < nodeList.getLength(); i++) { nodeArray.add(nodeList.item(i)); } value = xqconn.createSequence(nodeArray.iterator()); } // Bind value with external variable if (value != null && xqType != null) { if (value instanceof XQSequence) { exp.bindSequence(variable, (XQSequence) value); } else { if (xqType instanceof XQItemType) { exp.bindObject(variable, value, (XQItemType) xqType); } } } } // Set context node Node contextNode = (ctx.getRootNode() == null) ? DOMUtils.newDocument() : ctx.getRootNode(); contextNode.setUserData(XQuery10BpelFunctions.USER_DATA_KEY_FUNCTION_RESOLVER, funcResolver, null); exp.bindItem(XQConstants.CONTEXT_ITEM, xqconn.createItemFromNode(contextNode, xqconn.createNodeType())); // Execute query XQResultSequence result = exp.executeQuery(); // Cast Saxon result to Java result Object evalResult = getResultValue(type, result); if ((evalResult != null) && __log.isDebugEnabled()) { __log.debug("Expression " + cexp.toString() + " generated result " + evalResult + " - type=" + evalResult.getClass().getName()); if (ctx.getRootNode() != null) { __log.debug("Was using context node " + DOMUtils.domToString(ctx.getRootNode())); } } return evalResult; } catch (XQException xqe) { // Extracting the real cause from all this wrapping isn't a simple task Throwable cause = (xqe.getCause() != null) ? xqe.getCause() : xqe; if (cause instanceof DynamicError) { Throwable th = ((DynamicError) cause).getException(); if (th != null) { cause = th; if (cause.getCause() != null) { cause = cause.getCause(); } } } throw new FaultException(cexp.getOwner().constants.qnSubLanguageExecutionFault, cause.getMessage(), cause); } catch (Throwable t) { __log.debug("Could not evaluate expression because of ", t); throw new FaultException(cexp.getOwner().constants.qnSubLanguageExecutionFault, t.getMessage(), t); } } /** * Return opaque object embedded in XQuery Item * * @param item item * * @return type * * @throws XQException XQException */ private Object getItemValue(XQItem item) throws XQException { XQItemType itemType = item.getItemType(); Object itemValue = null; switch (itemType.getBaseType()) { case XQItemType.XQBASETYPE_BOOLEAN: itemValue = item.getBoolean(); break; case XQItemType.XQBASETYPE_DECIMAL: itemValue = item.getDouble(); break; case XQItemType.XQBASETYPE_BYTE: itemValue = item.getByte(); break; case XQItemType.XQBASETYPE_FLOAT: itemValue = item.getFloat(); break; case XQItemType.XQBASETYPE_INT: case XQItemType.XQBASETYPE_INTEGER: itemValue = item.getInt(); break; case XQItemType.XQBASETYPE_LONG: itemValue = item.getLong(); break; case XQItemType.XQBASETYPE_ANYTYPE: itemValue = item.getNode(); break; case XQItemType.XQBASETYPE_ANYURI: itemValue = item.getNodeUri(); break; case XQItemType.XQBASETYPE_SHORT: itemValue = item.getShort(); break; case XQItemType.XQBASETYPE_STRING: case XQItemType.XQBASETYPE_ANYATOMICTYPE: itemValue = item.getAtomicValue(); break; } return itemValue; } /** * Return XQuery type corresponding to given value * * @param xqconn XQuery connection * @param value value * * @return type * * @throws XQException XQException */ private XQSequenceType getItemType(XQConnection xqconn, Object value) throws XQException { XQSequenceType xqType = null; if (value instanceof Long) { xqType = xqconn.createAtomicType(XQItemType.XQBASETYPE_LONG); } else if (value instanceof String) { xqType = xqconn.createAtomicType(XQItemType.XQBASETYPE_STRING); } else if (value instanceof Node) { xqType = xqconn.createNodeType(); } else if (value instanceof NodeList || value instanceof XQSequence) { XQItemType xqItemType = xqconn.createNodeType(); xqType = xqconn.createSequenceType(xqItemType, XQSequenceType.OCC_ZERO_OR_MORE); } return xqType; } /** * Cast XQuery sequence into an opaque list * * @param type type * @param result result * * @return value * * @throws XQException XQException */ private Object getResultValue(QName type, XQResultSequence result) throws XQException { Document document = DOMUtils.newDocument(); Object resultValue = null; if (XPathConstants.NODESET.equals(type)) { List list = new ArrayList(); while (result.next()) { Object itemValue = getItemValue(result.getItem()); if (itemValue instanceof Node) { itemValue = DOMUtils.cloneNode(document, (Node) itemValue); } if (itemValue != null) { list.add(itemValue); } } resultValue = list; } else if (XPathConstants.NODE.equals(type)) { XQItem item = null; if (result.count() > 0) { result.first(); if (result.isOnItem()) { item = result.getItem(); } } if (item != null) { resultValue = getItemValue(item); if (resultValue instanceof Node) { resultValue = DOMUtils.cloneNode(document, (Node) resultValue); } } } else if (XPathConstants.STRING.equals(type)) { resultValue = result.getSequenceAsString(new Properties()); } else if (XPathConstants.NUMBER.equals(type)) { resultValue = result.getSequenceAsString(new Properties()); resultValue = Integer.parseInt((String) resultValue); } else if (XPathConstants.BOOLEAN.equals(type)) { resultValue = result.getSequenceAsString(new Properties()); resultValue = Boolean.parseBoolean((String) resultValue); } return resultValue; } }