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/* * Created on Jun 22, 2005 * * 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. * * Copyright @2005 the original author or authors. */ package org.springmodules.remoting.xmlrpc.dom; import javax.xml.parsers.DocumentBuilder; import javax.xml.parsers.DocumentBuilderFactory; import javax.xml.parsers.ParserConfigurationException; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.springframework.util.xml.SimpleSaxErrorHandler; import org.springmodules.remoting.xmlrpc.XmlRpcWriterException; import org.springmodules.remoting.xmlrpc.support.XmlRpcArray; import org.springmodules.remoting.xmlrpc.support.XmlRpcBase64; import org.springmodules.remoting.xmlrpc.support.XmlRpcBoolean; import org.springmodules.remoting.xmlrpc.support.XmlRpcDateTime; import org.springmodules.remoting.xmlrpc.support.XmlRpcDouble; import org.springmodules.remoting.xmlrpc.support.XmlRpcElement; import org.springmodules.remoting.xmlrpc.support.XmlRpcElementNames; import org.springmodules.remoting.xmlrpc.support.XmlRpcInteger; import org.springmodules.remoting.xmlrpc.support.XmlRpcScalar; import org.springmodules.remoting.xmlrpc.support.XmlRpcString; import org.springmodules.remoting.xmlrpc.support.XmlRpcStruct; import org.springmodules.remoting.xmlrpc.support.XmlRpcStruct.XmlRpcMember; import org.w3c.dom.Document; import org.w3c.dom.Element; import org.w3c.dom.Text; import org.xml.sax.ErrorHandler; /** * <p> * Template for XML-RPC request/response writes that use DOM to create XML. * </p> * * @author Alex Ruiz * * @version $Revision$ $Date$ */ public abstract class AbstractDomXmlRpcWriter { /** * <p> * Implementation of <code>org.xml.sax.ErrorHandler</code> for custom * handling of XML parsing errors and warnings. * </p> * <p> * If not set, a default <code>{@link SimpleSaxErrorHandler}</code> is used * that simply logs warnings using the logger instance of the view class, and * rethrows errors to discontinue the XML transformation. * </p> * * @see org.springframework.util.xml.SimpleSaxErrorHandler */ private ErrorHandler errorHandler; protected final Log logger = LogFactory.getLog(getClass()); public AbstractDomXmlRpcWriter() { super(); setErrorHandler(new SimpleSaxErrorHandler(logger)); } /** * Creates the XML representation of the given XML-RPC array. * * @param array * the XML-RPC array. * @param document * the XML document used to create new XML elements. * @return the created XML element. */ protected final Element createArrayElement(XmlRpcArray array, Document document) { Element dataElement = document.createElement(XmlRpcElementNames.DATA); XmlRpcElement[] elements = array.getElements(); int elementCount = elements.length; for (int i = 0; i < elementCount; i++) { Element valueElement = createValueElement(elements[i], document); dataElement.appendChild(valueElement); } Element arrayElement = document.createElement(XmlRpcElementNames.ARRAY); arrayElement.appendChild(dataElement); return arrayElement; } /** * Creates an empty XML document. * * @return the created XML document. */ protected final Document createEmptyXmlDocument() { try { DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance(); if (logger.isDebugEnabled()) { logger.debug("Using JAXP implementation [" + factory + "]"); } DocumentBuilder docBuilder = factory.newDocumentBuilder(); docBuilder.setErrorHandler(errorHandler); return docBuilder.newDocument(); } catch (ParserConfigurationException exception) { throw new XmlRpcWriterException("Parser configuration exception", exception); } } /** * Creates a XML representation of the given member of a XML-RPC struct. * * @param member * the member of a XML-RPC struct. * @param document * the XML document used to create new XML elements. * @return the created XML element. */ protected final Element createMemberElement(XmlRpcMember member, Document document) { Element nameElement = document.createElement(XmlRpcElementNames.NAME); Text text = document.createTextNode(member.name); nameElement.appendChild(text); Element valueElement = createValueElement(member.value, document); Element memberElement = document.createElement(XmlRpcElementNames.MEMBER); memberElement.appendChild(nameElement); memberElement.appendChild(valueElement); return memberElement; } /** * Creates the XML representation of the given XML-RPC parameter. * * @param parameter * the XML-RPC parameter. * @param document * the XML document used to create new XML elements. * @return the created XML element. */ protected final Element createParameterElement(XmlRpcElement parameter, Document document) { Element valueElement = createValueElement(parameter, document); Element parameterElement = document.createElement(XmlRpcElementNames.PARAM); parameterElement.appendChild(valueElement); return parameterElement; } /** * Creates the XML representation of the given XML-RPC parameters. * * @param parameters * the XML-RPC parameters. * @param document * the XML document used to create new XML elements. * @return the created XML element. */ protected final Element createParametersElement(XmlRpcElement[] parameters, Document document) { Element parametersElement = document.createElement(XmlRpcElementNames.PARAMS); int parameterCount = parameters.length; for (int i = 0; i < parameterCount; i++) { Element parameterElement = createParameterElement(parameters[i], document); parametersElement.appendChild(parameterElement); } return parametersElement; } /** * Creates the XML representation of the given XML-RPC scalar value. * * @param elementName * the name of the XML element to create. * @param value * the XML-RPC scalar value. * @param document * the DOM document to add the created XML element to. * @return the created XML element. */ protected final Element createScalarElement(String elementName, XmlRpcElement value, Document document) { Element scalarElement = document.createElement(elementName); XmlRpcScalar scalarValue = (XmlRpcScalar) value; Text text = document.createTextNode(scalarValue.getValueAsString()); scalarElement.appendChild(text); return scalarElement; } /** * Creates the XML representation of the given XML-RPC struct. * * @param struct * the XML-RPC struct. * @param document * the XML document used to create new XML elements. * @return the created XML element. */ protected final Element createStructElement(XmlRpcStruct struct, Document document) { Element structElement = document.createElement(XmlRpcElementNames.STRUCT); XmlRpcMember[] members = struct.getMembers(); int memberCount = members.length; for (int i = 0; i < memberCount; i++) { Element memberElement = createMemberElement(members[i], document); structElement.appendChild(memberElement); } return structElement; } /** * Creates the XML representation of the given XML-RPC value. * * @param value * the XML-RPC value. * @param document * the XML document used to create new XML elements. * @return the created XML element. */ protected final Element createValueElement(XmlRpcElement value, Document document) { Element child = null; if (value instanceof XmlRpcArray) { child = createArrayElement((XmlRpcArray) value, document); } else if (value instanceof XmlRpcBase64) { child = createScalarElement(XmlRpcElementNames.BASE_64, value, document); } else if (value instanceof XmlRpcBoolean) { child = createScalarElement(XmlRpcElementNames.BOOLEAN, value, document); } else if (value instanceof XmlRpcDateTime) { child = createScalarElement(XmlRpcElementNames.DATE_TIME, value, document); } else if (value instanceof XmlRpcDouble) { child = createScalarElement(XmlRpcElementNames.DOUBLE, value, document); } else if (value instanceof XmlRpcInteger) { child = createScalarElement(XmlRpcElementNames.I4, value, document); } else if (value instanceof XmlRpcString) { child = createScalarElement(XmlRpcElementNames.STRING, value, document); } else if (value instanceof XmlRpcStruct) { child = createStructElement((XmlRpcStruct) value, document); } Element valueElement = document.createElement(XmlRpcElementNames.VALUE); valueElement.appendChild(child); return valueElement; } public final void setErrorHandler(ErrorHandler newErrorHandler) { errorHandler = newErrorHandler; } }