Java tutorial
/* * Copyright (c) 2008 Los Alamos National Security, LLC. * * Los Alamos National Laboratory * Research Library * Digital Library Research & Prototyping Team * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA * */ package gov.lanl.adore.djatoka.openurl; import java.io.ByteArrayOutputStream; import java.io.IOException; import java.io.UnsupportedEncodingException; import java.net.URI; import java.net.URISyntaxException; import java.util.HashMap; import java.util.Properties; import javax.servlet.http.HttpServletResponse; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import com.fasterxml.jackson.databind.ObjectMapper; import com.fasterxml.jackson.databind.node.ObjectNode; import gov.lanl.adore.djatoka.DjatokaException; import gov.lanl.adore.djatoka.IExtract; import gov.lanl.adore.djatoka.io.FormatConstants; import gov.lanl.adore.djatoka.kdu.KduExtractExe; import gov.lanl.adore.djatoka.util.IOUtils; import gov.lanl.adore.djatoka.util.ImageRecord; import gov.lanl.util.HttpDate; import info.freelibrary.djatoka.view.IdentifierResolver; import info.openurl.oom.ContextObject; import info.openurl.oom.OpenURLRequest; import info.openurl.oom.OpenURLRequestProcessor; import info.openurl.oom.OpenURLResponse; import info.openurl.oom.Service; import info.openurl.oom.config.ClassConfig; import info.openurl.oom.config.OpenURLConfig; import info.openurl.oom.entities.ServiceType; /** * The OpenURLJP2KMetadata OpenURL Service * * @author Ryan Chute */ public class OpenURLJP2KMetadata implements Service, FormatConstants { private static Logger LOGGER = LoggerFactory.getLogger(OpenURLJP2KMetadata.class); private static final String DEFAULT_IMPL_CLASS = IdentifierResolver.class.getCanonicalName(); private static final String PROPS_KEY_IMPL_CLASS = "OpenURLJP2KService.referentResolverImpl"; private static final String SVC_ID = "info:lanl-repo/svc/getMetadata"; private static final String RESPONSE_TYPE = "application/json"; private static String implClass = null; private static Properties props = new Properties(); /** * Construct an info:lanl-repo/svc/getMetadata web service class. Initializes Referent Resolver instance using * OpenURLJP2KService.referentResolverImpl property. * * @param openURLConfig OOM Properties forwarded from OpenURLServlet * @param classConfig Implementation Properties forwarded from OpenURLServlet * @throws ResolverException */ public OpenURLJP2KMetadata(final OpenURLConfig openURLConfig, final ClassConfig classConfig) throws ResolverException { try { if (!ReferentManager.isInit()) { props = IOUtils.loadConfigByCP(classConfig.getArg("props")); implClass = props.getProperty(PROPS_KEY_IMPL_CLASS, DEFAULT_IMPL_CLASS); ReferentManager.init((IReferentResolver) Class.forName(implClass).newInstance(), props); } } catch (final IOException e) { throw new ResolverException("Error attempting to open props file from classpath, disabling " + SVC_ID + " : " + e.getMessage()); } catch (final Exception e) { throw new ResolverException("Unable to inititalize implementation: " + props.getProperty(implClass) + " - " + e.getMessage()); } } /** * Returns the OpenURL service identifier for this implementation of info.openurl.oom.Service */ @Override public URI getServiceID() throws URISyntaxException { return new URI(SVC_ID); } /** * Returns the OpenURLResponse of a JSON object defining the core image properties. Having obtained a result, this * method is then responsible for transforming it into an OpenURLResponse that acts as a proxy for * HttpServletResponse. */ @Override public OpenURLResponse resolve(final ServiceType serviceType, final ContextObject contextObject, final OpenURLRequest openURLRequest, final OpenURLRequestProcessor processor) { String responseFormat = RESPONSE_TYPE; int status = HttpServletResponse.SC_OK; ByteArrayOutputStream baos = new ByteArrayOutputStream(); try { final ObjectMapper mapper = new ObjectMapper(); final ObjectNode rootNode = mapper.createObjectNode(); final IExtract jp2 = new KduExtractExe(); ImageRecord r = ReferentManager.getImageRecord(contextObject.getReferent()); r = jp2.getMetadata(r); rootNode.put("identifier", r.getIdentifier()); rootNode.put("imagefile", r.getImageFile()); rootNode.put("width", r.getWidth()); rootNode.put("height", r.getHeight()); rootNode.put("dwtLevels", r.getDWTLevels()); rootNode.put("levels", r.getLevels()); rootNode.put("compositingLayerCount", r.getCompositingLayerCount()); mapper.writeValue(baos, rootNode); } catch (final DjatokaException e) { responseFormat = "text/plain"; status = HttpServletResponse.SC_NOT_FOUND; } catch (final Exception e) { baos = new ByteArrayOutputStream(); try { if (e.getMessage() != null) { baos.write(e.getMessage().getBytes("UTF-8")); } else { LOGGER.error(e.getMessage(), e); baos.write("Internal Server Error: ".getBytes()); } } catch (final UnsupportedEncodingException e1) { e1.printStackTrace(); } catch (final IOException e2) { e2.printStackTrace(); } responseFormat = "text/plain"; status = HttpServletResponse.SC_INTERNAL_SERVER_ERROR; } final HashMap<String, String> header_map = new HashMap<String, String>(); header_map.put("Content-Length", baos.size() + ""); header_map.put("Date", HttpDate.getHttpDate()); return new OpenURLResponse(status, responseFormat, baos.toByteArray(), header_map); } }