/** * Copyright (C) 2007 - 2016 52°North Initiative for Geospatial Open Source * Software GmbH * * 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. */ package org.n52.wps.server; import java.io.IOException; import java.io.InputStream; import net.opengis.wps.x100.ProcessDescriptionType; import net.opengis.wps.x100.ProcessDescriptionsDocument; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.apache.xmlbeans.XmlException; import org.apache.xmlbeans.XmlOptions; /** * This class has to be extended in order to be served through the WPS. * The class file should also include a description file of the algorithm. This file has to be * valid against the describeProcess.xsd. The file has to be placed in the folder of the class file and has * to be named the same as the Algorithm. * * <p>If you want to apply a different initialization method, just override the initializeDescription() method. * * NOTE: This class is an adapter and it is recommended to extend this. * @author foerster * */ public abstract class AbstractAlgorithm implements IAlgorithm { private ProcessDescriptionType description; // private, force access through getter method for lazy loading. private final String wkName; private static Logger LOGGER = LoggerFactory.getLogger(AbstractAlgorithm.class); /** * default constructor, calls the initializeDescription() Method */ public AbstractAlgorithm() { this.wkName = this.getClass().getName(); } /** * default constructor, calls the initializeDescription() Method */ public AbstractAlgorithm(String wellKnownName) { this.wkName = wellKnownName; } /** * This method should be overwritten, in case you want to have a way of initializing. * * In detail it looks for a xml descfile, which is located in the same directory as the implementing class and has the same * name as the class, but with the extension XML. * @return */ protected ProcessDescriptionType initializeDescription() { String className = this.getClass().getName().replace(".", "/"); InputStream xmlDesc = this.getClass().getResourceAsStream("/" + className + ".xml"); try { XmlOptions option = new XmlOptions(); option.setLoadTrimTextBuffer(); ProcessDescriptionsDocument doc = ProcessDescriptionsDocument.Factory.parse(xmlDesc, option); if(doc.getProcessDescriptions().getProcessDescriptionArray().length == 0) { LOGGER.warn("ProcessDescription does not contain correct any description"); return null; } // Checking that the process name (full class name or well-known name) matches the identifier. if(!doc.getProcessDescriptions().getProcessDescriptionArray(0).getIdentifier().getStringValue().equals(this.getClass().getName()) && !doc.getProcessDescriptions().getProcessDescriptionArray(0).getIdentifier().getStringValue().equals(this.getWellKnownName())) { doc.getProcessDescriptions().getProcessDescriptionArray(0).getIdentifier().setStringValue(this.getClass().getName()); LOGGER.warn("Identifier was not correct, was changed now temporary for server use to " + this.getClass().getName() + ". Please change it later in the description!"); } return doc.getProcessDescriptions().getProcessDescriptionArray(0); } catch(IOException e) { LOGGER.warn("Could not initialize algorithm, parsing error: " + this.getClass().getName(), e); } catch(XmlException e) { LOGGER.warn("Could not initialize algorithm, parsing error: " + this.getClass().getName(), e); } return null; } @Override public synchronized ProcessDescriptionType getDescription() { if (description == null) { description = initializeDescription(); } return description; } @Override public boolean processDescriptionIsValid() { return getDescription().validate(); } @Override public String getWellKnownName() { return this.wkName; } }