org.apache.ode.bpel.compiler.v2.xpath10.jaxp.JaxpVariableResolver.java Source code

Introduction

Here is the source code for org.apache.ode.bpel.compiler.v2.xpath10.jaxp.JaxpVariableResolver.java

Source

/*
 * 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.xpath10.jaxp;

import javax.xml.namespace.QName;
import javax.xml.xpath.XPathVariableResolver;

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.v2.CompilerContext;
import org.apache.ode.bpel.rtrep.v2.OElementVarType;
import org.apache.ode.bpel.rtrep.v2.OLink;
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.xpath10.OXPath10Expression;
import org.apache.ode.bpel.rtrep.v2.xpath10.OXPath10ExpressionBPEL20;
import org.apache.ode.utils.DOMUtils;
import org.apache.ode.utils.Namespaces;
import org.apache.ode.utils.msg.MessageBundle;
import org.w3c.dom.Document;

/**
 * This is a mock implementation of the XPathVariableResolver for compilation. It always returns an empty string which
 * allows execution of XPath expressions even if we don't have any values yet. This way we can easily rule out invalid
 * variables and isolate properly BPEL variables.
 */
public class JaxpVariableResolver implements XPathVariableResolver {
    private static final Log __log = LogFactory.getLog(XPathVariableResolver.class);

    private static final XPathMessages __msgs = MessageBundle.getMessages(XPathMessages.class);

    private CompilerContext _cctx;

    private OXPath10Expression _oxpath;

    public JaxpVariableResolver(CompilerContext cctx, OXPath10Expression oxpath) {
        _cctx = cctx;
        _oxpath = oxpath;
    }

    public Object resolveVariable(QName variableName) {
        __log.debug("JAXP compiler: Resolving variable " + variableName);
        // Custom variables
        if ("ode".equals(variableName.getPrefix())
                || Namespaces.ODE_EXTENSION_NS.equals(variableName.getNamespaceURI())) {
            if ("pid".equals(variableName.getLocalPart()))
                return "";
        }

        try {
            String name = variableName.getLocalPart();
            if (_oxpath instanceof OXPath10ExpressionBPEL20
                    && ((OXPath10ExpressionBPEL20) _oxpath).isJoinExpression) {
                // these resolve to links
                OLink olink = _cctx.resolveLink(name);
                _oxpath.links.put(name, olink);
                return Boolean.TRUE;
            } else {
                int dot = name.indexOf('.');
                if (dot != -1)
                    name = name.substring(0, dot);
                OScope.Variable var = _cctx.resolveVariable(name);
                _oxpath.vars.put(name, var);
                return extractValue(var, var.type);
            }
        } catch (CompilationException e) {
            throw new WrappedResolverException(e);
        }
    }

    private Object extractValue(OScope.Variable var, OVarType varType) {
        if (varType instanceof OXsdTypeVarType) {
            return generateFromType(((OXsdTypeVarType) varType).xsdType);
        } else if (varType instanceof OElementVarType) {
            return generateFromType(((OElementVarType) varType).elementType);
        } else if (varType instanceof OMessageVarType) {
            // MR That's an ugly hack but otherwise, xpath compilation doesn't work
            if (((OMessageVarType) varType).parts.size() == 0)
                throw new WrappedResolverException(__msgs.errExpressionMessageNoPart(var.name));
            return extractValue(var, ((OMessageVarType) varType).parts.values().iterator().next().type);
        }
        return "";
    }

    private Object generateFromType(QName typeName) {
        if (typeName.getNamespaceURI().equals(Namespaces.XML_SCHEMA)) {
            if (typeName.getLocalPart().equals("int") || typeName.getLocalPart().equals("integer")
                    || typeName.getLocalPart().equals("short") || typeName.getLocalPart().equals("long")
                    || typeName.getLocalPart().equals("byte") || typeName.getLocalPart().equals("float")
                    || typeName.getLocalPart().equals("double")
                    || typeName.getLocalPart().equals("nonPositiveInteger")
                    || typeName.getLocalPart().equals("nonNegativeInteger")
                    || typeName.getLocalPart().equals("negativeInteger")
                    || typeName.getLocalPart().equals("unsignedLong")
                    || typeName.getLocalPart().equals("unsignedInt")
                    || typeName.getLocalPart().equals("unsignedShort")
                    || typeName.getLocalPart().equals("unsignedByte"))
                return 0;
            if (typeName.getLocalPart().equals("boolean"))
                return Boolean.TRUE;
            if (typeName.getLocalPart().equals("string"))
                return "";
        }
        Document doc = DOMUtils.newDocument();
        doc.appendChild(doc.createElement("empty"));
        return doc.getDocumentElement();
    }
}