org.treetank.service.jaxrx.util.WorkerHelper Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of jax-rx Show documentation
This project give the jax-rx interface to jax-rx.
The newest version!
/**
 * Copyright (c) 2011, University of Konstanz, Distributed Systems Group
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 * * Redistributions in binary form must reproduce the above copyright
 * notice, this list of conditions and the following disclaimer in the
 * documentation and/or other materials provided with the distribution.
 * * Neither the name of the University of Konstanz nor the
 * names of its contributors may be used to endorse or promote products
 * derived from this software without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL  BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

package org.treetank.service.jaxrx.util;

import java.io.InputStream;
import java.io.OutputStream;
import java.util.HashMap;
import java.util.Locale;
import java.util.Map;

import javax.ws.rs.WebApplicationException;
import javax.xml.stream.XMLEventReader;
import javax.xml.stream.XMLInputFactory;
import javax.xml.stream.XMLStreamException;

import org.treetank.api.INodeReadTrx;
import org.treetank.api.INodeWriteTrx;
import org.treetank.api.ISession;
import org.treetank.exception.TTException;
import org.treetank.service.jaxrx.enums.EIdAccessType;
import org.treetank.service.xml.serialize.XMLSerializer;
import org.treetank.service.xml.serialize.XMLSerializer.XMLSerializerBuilder;
import org.treetank.service.xml.serialize.XMLSerializerProperties;
import org.treetank.service.xml.shredder.EShredderInsert;
import org.treetank.service.xml.shredder.XMLShredder;

/**
 * This class contains methods that are respectively used by this worker classes
 * (NodeIdRepresentation.java and DatabaseRepresentation.java)
 * 
 * @author Patrick Lang, Lukas Lewandowski, University of Konstanz
 * 
 */

public final class WorkerHelper {

    /**
     * The map containing the available access types.
     */
    private final transient Map typeList;

    /**
     * This constructor initializes the {@link EIdAccessType}s.
     */
    private WorkerHelper() {
        typeList = new HashMap();
        typeList.put("FIRSTCHILD()", EIdAccessType.FIRSTCHILD);
        typeList.put("LASTCHILD()", EIdAccessType.LASTCHILD);
        typeList.put("RIGHTSIBLING()", EIdAccessType.RIGHTSIBLING);
        typeList.put("LEFTSIBLING()", EIdAccessType.LEFTSIBLING);
    }

    /**
     * The instance variable for singleton.
     */
    private static final transient WorkerHelper INSTANCE = new WorkerHelper();

    /**
     * Shreds a given InputStream
     * 
     * @param wtx
     *            current write transaction reference
     * @param value
     *            InputStream to be shred
     */
    public static void shredInputStream(final INodeWriteTrx wtx, final InputStream value,
        final EShredderInsert child) {
        final XMLInputFactory factory = XMLInputFactory.newInstance();
        factory.setProperty(XMLInputFactory.SUPPORT_DTD, false);
        XMLEventReader parser;
        try {
            parser = factory.createXMLEventReader(value);
        } catch (final XMLStreamException xmlse) {
            throw new WebApplicationException(xmlse);
        }

        try {
            final XMLShredder shredder = new XMLShredder(wtx, parser, child);
            shredder.call();
        } catch (final Exception exce) {
            throw new WebApplicationException(exce);
        }
    }

    /**
     * This method creates a new XMLSerializer reference
     * 
     * @param session
     *            Associated session.
     * @param out
     *            OutputStream
     * 
     * @param serializeXMLDec
     *            specifies whether XML declaration should be shown
     * @param serializeRest
     *            specifies whether node id should be shown
     * 
     * @return new XMLSerializer reference
     */
    public static XMLSerializer serializeXML(final ISession session, final OutputStream out,
        final boolean serializeXMLDec, final boolean serializeRest, final Long revision) {
        final XMLSerializerBuilder builder;
        if (revision == null)
            builder = new XMLSerializerBuilder(session, out);
        else
            builder = new XMLSerializerBuilder(session, out, revision);
        builder.setREST(serializeRest);
        builder.setID(serializeRest);
        builder.setDeclaration(serializeXMLDec);
        final XMLSerializer serializer = builder.build();
        return serializer;
    }

    /**
     * This method creates a new XMLSerializer reference
     * 
     * @param session
     *            Associated session.
     * @param out
     *            OutputStream
     * 
     * @param serializeXMLDec
     *            specifies whether XML declaration should be shown
     * @param serializeRest
     *            specifies whether node id should be shown
     * 
     * @return new XMLSerializer reference
     */
    public static XMLSerializer serializeXML(final ISession session, final OutputStream out,
        final boolean serializeXMLDec, final boolean serializeRest, final Long nodekey, final Long revision) {
        final XMLSerializerProperties props = new XMLSerializerProperties();
        final XMLSerializerBuilder builder;
        if (revision == null && nodekey == null)
            builder = new XMLSerializerBuilder(session, out);
        else if (revision != null && nodekey == null)
            builder = new XMLSerializerBuilder(session, out, revision);
        else if (revision == null && nodekey != null)
            builder = new XMLSerializerBuilder(session, nodekey, out, props);
        else
            builder = new XMLSerializerBuilder(session, nodekey, out, props, revision);
        builder.setREST(serializeRest);
        builder.setID(serializeRest);
        builder.setDeclaration(serializeXMLDec);
        builder.setIndend(false);
        final XMLSerializer serializer = builder.build();
        return serializer;
    }

    /**
     * This method creates a new StringBuilder reference
     * 
     * @return new StringBuilder reference
     */
    public StringBuilder createStringBuilderObject() {
        return new StringBuilder();
    }

    /**
     * This method closes all open treetank connections concerning a
     * NodeWriteTrx.
     * 
     * @param abortTransaction
     *            true if the transaction has to be aborted, false otherwise.
     * @param wtx
     *            INodeWriteTrx to be closed
     * @param ses
     *            ISession to be closed
     * @throws TreetankException
     */
    public static void closeWTX(final boolean abortTransaction, final INodeWriteTrx wtx, final ISession ses)
        throws TTException {
        synchronized (ses) {
            if (abortTransaction) {
                wtx.abort();
            }
            ses.close();
        }
    }

    /**
     * This method closes all open treetank connections concerning a
     * NodeReadTrx.
     * 
     * @param rtx
     *            INodeReadTrx to be closed
     * @param ses
     *            ISession to be closed
     * @throws TTException
     */
    public static void closeRTX(final INodeReadTrx rtx, final ISession ses) throws TTException {
        synchronized (ses) {
            ses.close();
        }
    }

    /**
     * This method checks the variable URL path after the node id resource (e.g.
     * http://.../factbook/3/[ACCESSTYPE]) for the available access type to
     * identify a node. The access types are defined in {@link EIdAccessType}.
     * 
     * @param accessType
     *            The access type as String value encoded in the URL request.
     * @return The valid access type or null otherwise.
     */
    public EIdAccessType validateAccessType(final String accessType) {
        return typeList.get(accessType.toUpperCase(Locale.US));
    }

    /**
     * This method return the singleton instance.
     * 
     * @return The single instance.
     */
    public static WorkerHelper getInstance() {
        return INSTANCE;
    }
}