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.compiler.v2.xquery10.compiler; import java.net.URI; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import java.util.Set; import javax.xml.namespace.QName; import javax.xml.transform.Source; import javax.xml.transform.TransformerFactory; import javax.xml.xquery.XQConnection; import javax.xml.xquery.XQConstants; import javax.xml.xquery.XQDataSource; import javax.xml.xquery.XQException; import javax.xml.xquery.XQItemType; import javax.xml.xquery.XQPreparedExpression; import javax.xml.xquery.XQSequence; import javax.xml.xquery.XQStaticContext; import net.sf.saxon.Configuration; import net.sf.saxon.om.Validation; 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.compiler.WrappedResolverException; import org.apache.ode.bpel.compiler.XPathMessages; import org.apache.ode.bpel.compiler.api.CompilationException; import org.apache.ode.bpel.compiler.bom.Expression; import org.apache.ode.bpel.compiler.v2.xpath20.JaxpFunctionResolver; import org.apache.ode.bpel.compiler.v2.CompilerContext; import org.apache.ode.bpel.compiler.v2.ExpressionCompiler; import org.apache.ode.bpel.compiler.v2.xpath10.XslCompilationErrorListener; import org.apache.ode.bpel.compiler.v2.xpath20.JaxpVariableResolver; import org.apache.ode.bpel.rtrep.common.Constants; import org.apache.ode.bpel.rtrep.v2.OConstantVarType; import org.apache.ode.bpel.rtrep.v2.OElementVarType; import org.apache.ode.bpel.rtrep.v2.OExpression; import org.apache.ode.bpel.rtrep.v2.OLValueExpression; import org.apache.ode.bpel.rtrep.v2.OMessageVarType; import org.apache.ode.bpel.rtrep.v2.OScope; import org.apache.ode.bpel.rtrep.v2.OVarType; import org.apache.ode.bpel.rtrep.v2.OXsdTypeVarType; import org.apache.ode.bpel.rtrep.v2.OMessageVarType.Part; import org.apache.ode.bpel.rtrep.v2.xquery10.OXQuery10ExpressionBPEL20; import org.apache.ode.utils.DOMUtils; import org.apache.ode.utils.NSContext; import org.apache.ode.utils.Namespaces; import org.apache.ode.utils.msg.MessageBundle; import org.apache.ode.utils.xsl.XslTransformHandler; import org.apache.xml.utils.XMLChar; import org.w3c.dom.Node; import org.w3c.dom.NodeList; /** * XQuery compiler based on the SAXON implementation. */ public class XQuery10ExpressionCompilerImpl implements ExpressionCompiler { protected static final Log __log = LogFactory.getLog(XQuery10ExpressionCompilerImpl.class); protected String _bpelNS; protected QName _qnLinkStatus; protected QName _qnVarProp; protected QName _qnVarData; protected QName _qnXslTransform; protected final XPathMessages __msgs = MessageBundle.getMessages(XPathMessages.class); protected Map<String, String> _properties = new HashMap<String, String>(); protected CompilerContext _compilerContext; public XQuery10ExpressionCompilerImpl(String bpelNS) { _bpelNS = bpelNS; _qnLinkStatus = new QName(_bpelNS, Constants.EXT_FUNCTION_GETLINKSTATUS); _qnVarProp = new QName(_bpelNS, Constants.EXT_FUNCTION_GETVARIABLEPROPERTY); _qnVarData = new QName(_bpelNS, Constants.EXT_FUNCTION_GETVARIABLEDATA); _qnXslTransform = new QName(_bpelNS, Constants.EXT_FUNCTION_DOXSLTRANSFORM); _properties.put("runtime-class", "org.apache.ode.bpel.rtrep.v2.xquery10.runtime.XQuery10ExpressionRuntime"); TransformerFactory trsf = new net.sf.saxon.TransformerFactoryImpl(); XslTransformHandler.getInstance().setTransformerFactory(trsf); } public void setCompilerContext(CompilerContext compilerContext) { _compilerContext = compilerContext; XslCompilationErrorListener xe = new XslCompilationErrorListener(compilerContext); XslTransformHandler.getInstance().setErrorListener(xe); } /** * @see org.apache.ode.bpel.compiler.api.ExpressionCompiler#compileJoinCondition(java.lang.Object) */ public OExpression compileJoinCondition(Object source) throws CompilationException { return _compile((Expression) source, true); } /** * @see org.apache.ode.bpel.compiler.api.ExpressionCompiler#compile(java.lang.Object) */ public OExpression compile(Object source) throws CompilationException { return _compile((Expression) source, false); } /** * @see org.apache.ode.bpel.compiler.api.ExpressionCompiler#compileLValue(java.lang.Object) */ public OLValueExpression compileLValue(Object source) throws CompilationException { return (OLValueExpression) _compile((Expression) source, false); } /** * @see org.apache.ode.bpel.compiler.api.ExpressionCompiler#compile(java.lang.Object) */ private OExpression _compile(org.apache.ode.bpel.compiler.bom.Expression xquery, boolean isJoinCondition) throws CompilationException { OXQuery10ExpressionBPEL20 oexp = new OXQuery10ExpressionBPEL20(_compilerContext.getOProcess(), _qnVarData, _qnVarProp, _qnLinkStatus, _qnXslTransform, isJoinCondition); oexp.namespaceCtx = xquery.getNamespaceContext(); doJaxpCompile(oexp, xquery); return oexp; } private void doJaxpCompile(OXQuery10ExpressionBPEL20 out, Expression source) throws CompilationException { String xqueryStr; Node node = source.getExpression(); if (node == null) { throw new IllegalStateException("XQuery string and xpath node are both null"); } if (node.getNodeType() != Node.TEXT_NODE && node.getNodeType() != Node.ELEMENT_NODE && node.getNodeType() != Node.CDATA_SECTION_NODE) { throw new CompilationException(__msgs.errUnexpectedNodeTypeForXPath(DOMUtils.domToString(node))); } xqueryStr = DOMUtils.domToString(node); xqueryStr = xqueryStr.trim(); if (xqueryStr.length() == 0) { throw new CompilationException(__msgs.warnXPath20Syntax(DOMUtils.domToString(node), "empty string")); } try { XQDataSource xqds = new SaxonXQDataSource(); XQConnection xqconn = xqds.getConnection(); __log.debug("Compiling expression " + xqueryStr); Configuration configuration = ((SaxonXQConnection) xqconn).getConfiguration(); configuration.setAllNodesUntyped(true); configuration.setHostLanguage(Configuration.XQUERY); XQStaticContext staticContext = xqconn.getStaticContext(); JaxpFunctionResolver funcResolver = new JaxpFunctionResolver(_compilerContext, out, source.getNamespaceContext(), _bpelNS); JaxpVariableResolver variableResolver = new JaxpVariableResolver(_compilerContext, out); XQueryDeclarations declarations = new XQueryDeclarations(); NSContext nsContext = source.getNamespaceContext(); Set<String> prefixes = nsContext.getPrefixes(); if (!nsContext.getUriSet().contains(Namespaces.ODE_EXTENSION_NS)) { nsContext.register("ode", Namespaces.ODE_EXTENSION_NS); } for (String prefix : prefixes) { String uri = nsContext.getNamespaceURI(prefix); staticContext.declareNamespace(prefix, uri); if ("".equals(prefix)) { declarations.declareDefaultElementNamespace(uri); } else if ("bpws".equals(prefix)) { declarations.declareNamespace("bpws", "java:" + Constants.XQUERY_FUNCTION_HANDLER_COMPILER); } else { declarations.declareNamespace(prefix, uri); } } declarations.declareVariable(getQName(nsContext, Namespaces.ODE_EXTENSION_NS, "pid"), getQName(nsContext, Namespaces.XML_SCHEMA, "integer")); Map<URI, Source> schemaDocuments = _compilerContext.getSchemaSources(); for (URI schemaUri : schemaDocuments.keySet()) { Source schemaSource = schemaDocuments.get(schemaUri); // Don't add schema sources, since our Saxon library is not schema-aware. // configuration.addSchemaSource(schemaSource); } configuration.setSchemaValidationMode(Validation.SKIP); List<OScope.Variable> variables = _compilerContext.getAccessibleVariables(); Map<QName, QName> variableTypes = new HashMap<QName, QName>(); for (String variableName : getVariableNames(xqueryStr)) { OScope.Variable variable = getVariable(variables, variableName); if (variable == null) { continue; } OVarType type = variable.type; QName nameQName = getNameQName(variableName); QName typeQName = getTypeQName(variableName, type); variableTypes.put(nameQName, typeQName); String prefix = typeQName.getPrefix(); if (prefix == null || "".equals(prefix.trim())) { prefix = getPrefixForUri(nsContext, typeQName.getNamespaceURI()); } // don't declare typed variables, as our engine is not schema-aware // declarations.declareVariable(variable.name, typeQName); declarations.declareVariable(variableName); } // Add implicit declarations as prolog to the user-defined XQuery out.xquery = declarations.toString() + xqueryStr; // Check the XQuery for compilation errors xqconn.setStaticContext(staticContext); XQPreparedExpression exp = xqconn.prepareExpression(out.xquery); // Pre-evaluate variables and functions by executing query node.setUserData(XQuery10BpelFunctions.USER_DATA_KEY_FUNCTION_RESOLVER, funcResolver, null); exp.bindItem(XQConstants.CONTEXT_ITEM, xqconn.createItemFromNode(node, xqconn.createNodeType())); // Bind external variables to dummy runtime values for (QName variable : exp.getAllUnboundExternalVariables()) { QName typeQName = variableTypes.get(variable); Object value = variableResolver.resolveVariable(variable); if (typeQName != null) { if (value.getClass().getName().startsWith("java.lang")) { exp.bindAtomicValue(variable, value.toString(), xqconn.createAtomicType(XQItemType.XQBASETYPE_ANYATOMICTYPE)); } else if (value instanceof Node) { exp.bindNode(variable, (Node) value, xqconn.createNodeType()); } else if (value instanceof NodeList) { NodeList nodeList = (NodeList) value; ArrayList nodeArray = new ArrayList(); for (int i = 0; i < nodeList.getLength(); i++) { nodeArray.add(nodeList.item(i)); } XQSequence sequence = xqconn.createSequence(nodeArray.iterator()); exp.bindSequence(variable, sequence); } } } // evaluate the expression so as to initialize the variables try { exp.executeQuery(); } catch (XQException xpee) { // swallow errors caused by uninitialized variables } } catch (XQException xqe) { __log.debug(xqe); __log.info("Couldn't validate properly expression " + xqueryStr); } catch (WrappedResolverException wre) { if (wre._compilationMsg != null) throw new CompilationException(wre._compilationMsg, wre); if (wre.getCause() instanceof CompilationException) throw (CompilationException) wre.getCause(); throw wre; } } public Map<String, String> getProperties() { return _properties; } private String getQName(NSContext nsContext, String uri, String localPart) { String prefix = getPrefixForUri(nsContext, uri); return (prefix == null ? localPart : (prefix + ":" + localPart)); } private String getPrefixForUri(NSContext nsContext, String uri) { Set<String> prefixes = nsContext.getPrefixes(); for (String prefix : prefixes) { String anUri = (nsContext.getNamespaceURI(prefix)); if (anUri != null && anUri.equals(uri)) { return prefix; } } return null; } private List<String> getVariableNames(String xquery) { List<String> variableNames = new ArrayList<String>(); for (int index = xquery.indexOf("$"); index != -1; index = xquery.indexOf("$")) { StringBuffer variableName = new StringBuffer(); for (char ch = xquery.charAt(++index); XMLChar.isNCName(ch); ch = xquery.charAt(++index)) { variableName.append(ch); } variableNames.add(variableName.toString()); xquery = xquery.substring(index); } return variableNames; } private OScope.Variable getVariable(List<OScope.Variable> variables, String variableName) { String declaredVariable = getVariableDeclaredName(variableName); for (OScope.Variable variable : variables) { if (variable.name.equals(declaredVariable)) { return variable; } } return null; } private String getVariableDeclaredName(String variableReference) { int dotIndex = variableReference.indexOf("."); return dotIndex >= 0 ? variableReference.substring(0, dotIndex) : variableReference; } private String getVariablePartName(String variableReference) { int dotIndex = variableReference.indexOf("."); return dotIndex >= 0 ? variableReference.substring(dotIndex + 1) : ""; } private QName getNameQName(String variableName) { String prefix = null, localName = null; ; int colonIndex = variableName.indexOf(":"); if (colonIndex >= 0) { prefix = variableName.substring(0, colonIndex); localName = variableName.substring(colonIndex + 1); } else { prefix = ""; localName = variableName; } return new QName(prefix, localName); } private QName getTypeQName(String variableName, OVarType type) { QName typeQName = null; if (type instanceof OConstantVarType) { typeQName = new QName(Namespaces.XML_SCHEMA, "string", "xs"); } else if (type instanceof OElementVarType) { typeQName = ((OElementVarType) type).elementType; } else if (type instanceof OMessageVarType) { Part part = ((OMessageVarType) type).parts.get(getVariablePartName(variableName)); if (part != null) { typeQName = getTypeQName(variableName, part.type); } } else if (type instanceof OXsdTypeVarType) { typeQName = ((OXsdTypeVarType) type).xsdType; } return typeQName; } private class XQueryDeclarations { StringBuffer declarations = new StringBuffer(); public XQueryDeclarations() { } public void declareVariable(String name, QName type) { declareVariable(name, type.getPrefix() + ":" + type.getLocalPart()); } public void declareVariable(String name, String type) { declarations.append("declare variable ").append("$").append(name).append(" as ").append(type) .append(" external ").append(";\n"); } public void declareVariable(String name) { declarations.append("declare variable ").append("$").append(name).append(" external ").append(";\n"); } public void declareNamespace(String prefix, String uri) { declarations.append("declare namespace ").append(prefix).append("=").append("\"" + uri + "\"") .append(";\n"); } public void declareDefaultElementNamespace(String uri) { declarations.append("declare default element namespace ").append("\"" + uri + "\"").append(";\n"); } public String toString() { return declarations.toString(); } } }