Java tutorial
/* * Copyright (c) WSO2 Inc. (http://www.wso2.org) All Rights Reserved. * * WSO2 Inc. 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 com.connexta.arbitro.ctx; import java.io.ByteArrayInputStream; import java.io.IOException; import java.io.InputStream; import javax.xml.parsers.DocumentBuilderFactory; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import com.connexta.arbitro.Balana; import com.connexta.arbitro.ParsingException; import com.connexta.arbitro.XACMLConstants; import com.connexta.arbitro.ctx.xacml3.RequestCtx; import org.w3c.dom.Document; import org.w3c.dom.Element; import org.w3c.dom.Node; /** * Factory that creates the AbstractRequestCtx */ public class RequestCtxFactory { /** * Instance of this class */ private static volatile RequestCtxFactory factoryInstance; /** * the logger we'll use for all messages */ private static Log log = LogFactory.getLog(RequestCtxFactory.class); /** * Returns instance of <code>AbstractRequestCtx</code> based one the XACML version. * * @param root the node to parse for the <code>AbstractRequestCtx</code> * @return <code>AbstractRequestCtx</code> object * @throws ParsingException if the DOM node is invalid */ public AbstractRequestCtx getRequestCtx(Node root) throws ParsingException { String requestCtxNs = root.getNamespaceURI(); if (requestCtxNs != null) { if (XACMLConstants.REQUEST_CONTEXT_3_0_IDENTIFIER.equals(requestCtxNs.trim())) { return RequestCtx.getInstance(root); } else if (XACMLConstants.REQUEST_CONTEXT_1_0_IDENTIFIER.equals(requestCtxNs.trim()) || XACMLConstants.REQUEST_CONTEXT_2_0_IDENTIFIER.equals(requestCtxNs.trim())) { return com.connexta.arbitro.ctx.xacml2.RequestCtx.getInstance(root); } else { throw new ParsingException("Invalid namespace in XACML request"); } } else { log.warn("No Namespace defined in XACML request and Assume as XACML 3.0"); return RequestCtx.getInstance(root); } } /** * Returns instance of <code>AbstractRequestCtx</code> based one the XACML version. * * @param request the String to parse for the <code>AbstractRequestCtx</code> * @return <code>AbstractRequestCtx</code> object * @throws ParsingException if the request is invalid */ public AbstractRequestCtx getRequestCtx(String request) throws ParsingException { Node root = getXacmlRequest(request); String requestCtxNs = root.getNamespaceURI(); if (requestCtxNs != null) { if (XACMLConstants.REQUEST_CONTEXT_3_0_IDENTIFIER.equals(requestCtxNs.trim())) { return RequestCtx.getInstance(root); } else if (XACMLConstants.REQUEST_CONTEXT_1_0_IDENTIFIER.equals(requestCtxNs.trim()) || XACMLConstants.REQUEST_CONTEXT_2_0_IDENTIFIER.equals(requestCtxNs.trim())) { return com.connexta.arbitro.ctx.xacml2.RequestCtx.getInstance(root); } else { throw new ParsingException("Invalid namespace in XACML request"); } } else { log.warn("No Namespace defined in XACML request and Assume as XACML 3.0"); return RequestCtx.getInstance(root); } } /** * Returns instance of <code>AbstractRequestCtx</code> based one the XACML version. * * Creates a new <code>RequestCtx</code> by parsing XML from an input stream. Note that this a * convenience method, and it will not do schema validation by default. You should be parsing * the data yourself, and then providing the root node to the other <code>getInstance</code> * method. If you use this convenience method, you probably want to turn on validation by * setting the context schema file (see the programmer guide for more information on this). * * @param input input a stream providing the XML data * @return <code>AbstractRequestCtx</code> object * @throws ParsingException if the DOM node is invalid */ public AbstractRequestCtx getRequestCtx(InputStream input) throws ParsingException { Node root = InputParser.parseInput(input, "Request"); String requestCtxNs = root.getNamespaceURI(); if (requestCtxNs != null) { if (XACMLConstants.REQUEST_CONTEXT_3_0_IDENTIFIER.equals(requestCtxNs.trim())) { return RequestCtx.getInstance(root); } else if (XACMLConstants.REQUEST_CONTEXT_1_0_IDENTIFIER.equals(requestCtxNs.trim()) || XACMLConstants.REQUEST_CONTEXT_2_0_IDENTIFIER.equals(requestCtxNs.trim())) { return com.connexta.arbitro.ctx.xacml2.RequestCtx.getInstance(root); } else { throw new ParsingException("Invalid namespace in XACML request"); } } else { log.warn("No Namespace defined in XACML request and Assume as XACML 3.0"); return RequestCtx.getInstance(root); } } /** * Returns an instance of this factory. This method enforces a singleton model, meaning that * this always returns the same instance, creating the factory if it hasn't been requested * before. * * @return the factory instance */ public static RequestCtxFactory getFactory() { if (factoryInstance == null) { synchronized (RequestCtxFactory.class) { if (factoryInstance == null) { factoryInstance = new RequestCtxFactory(); } } } return factoryInstance; } /** * Creates DOM representation of the XACML request * * @param request XACML request as a String object * @return XACML request as a DOM element * @throws ParsingException throws, if fails */ public Element getXacmlRequest(String request) throws ParsingException { Document doc; ByteArrayInputStream inputStream; inputStream = new ByteArrayInputStream(request.getBytes()); DocumentBuilderFactory builder = Balana.getInstance().getBuilder(); if (builder == null) { throw new ParsingException("DOM Builder can not be null"); } try { doc = builder.newDocumentBuilder().parse(inputStream); } catch (Exception e) { throw new ParsingException("DOM of request element can not be created from String", e); } finally { try { inputStream.close(); } catch (IOException e) { log.error("Error in closing input stream of XACML request"); } } return doc.getDocumentElement(); } }