com.quanticate.opensource.compressingcontentstore.CompressingContentWriter.java Source code

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Here is the source code for com.quanticate.opensource.compressingcontentstore.CompressingContentWriter.java

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/* ====================================================================
  Copyright 2013 Quanticate Ltd
    
  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 com.quanticate.opensource.compressingcontentstore;

import java.io.OutputStream;
import java.nio.channels.Channels;
import java.nio.channels.WritableByteChannel;
import java.util.Locale;

import org.alfresco.error.AlfrescoRuntimeException;
import org.alfresco.repo.content.AbstractContentWriter;
import org.alfresco.service.cmr.repository.ContentIOException;
import org.alfresco.service.cmr.repository.ContentReader;
import org.alfresco.service.cmr.repository.ContentWriter;
import org.apache.commons.compress.compressors.CompressorException;
import org.apache.commons.compress.compressors.CompressorOutputStream;
import org.apache.commons.compress.compressors.CompressorStreamFactory;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

/**
 * A Content Writer which compresses data as it writes
 *  into the real Writer
 */
public class CompressingContentWriter extends AbstractContentWriter {
    private static Log logger = LogFactory.getLog(CompressingContentWriter.class);

    private ContentWriter realContentWriter;
    private String compressionType;

    public CompressingContentWriter(ContentWriter realContentWriter, ContentReader existingContentReader,
            String compressionType) {
        super(realContentWriter.getContentUrl(), existingContentReader);
        this.realContentWriter = realContentWriter;
        this.compressionType = compressionType;
    }

    public String getCompressionType() {
        return compressionType;
    }

    @Override
    public long getSize() {
        return -1L;
    }

    @Override
    protected ContentReader createReader() throws ContentIOException {
        return new DecompressingContentReader(realContentWriter.getReader());
    }

    @Override
    protected WritableByteChannel getDirectWritableChannel() throws ContentIOException {
        // Get the raw writer onto the real stream
        OutputStream rawOut = realContentWriter.getContentOutputStream();

        try {
            // Wrap that with the requested compression
            CompressorOutputStream compOut = new CompressorStreamFactory()
                    .createCompressorOutputStream(compressionType, rawOut);

            logger.info("Compressing " + realContentWriter.getContentUrl() + " with " + compressionType);

            // Turn that into a channel and return
            return Channels.newChannel(compOut);
        } catch (CompressorException e) {
            throw new AlfrescoRuntimeException("Error compressing", e);
        }
    }

    @Override
    public void setEncoding(String encoding) {
        super.setEncoding(encoding);
        realContentWriter.setEncoding(encoding);
    }

    @Override
    public void setLocale(Locale locale) {
        super.setLocale(locale);
        realContentWriter.setLocale(locale);
    }

    @Override
    public void setMimetype(String mimetype) {
        super.setMimetype(mimetype);
        realContentWriter.setMimetype(mimetype);
    }
}