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ActiveMQ example source code file (FileSystemBlobStrategy.java)

This example ActiveMQ source code file (FileSystemBlobStrategy.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Java - ActiveMQ tags/keywords

blobtransferpolicy, file, file, fileoutputstream, inputstream, io, ioexception, ioexception, jmsexception, jmsexception, malformedurlexception, net, network, unable, urisyntaxexception, urisyntaxexception, url

The ActiveMQ FileSystemBlobStrategy.java source code

/**
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF 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 org.apache.activemq.blob;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.MalformedURLException;
import java.net.URISyntaxException;
import java.net.URL;

import javax.jms.JMSException;

import org.apache.activemq.command.ActiveMQBlobMessage;

/**
 * {@link BlobUploadStrategy} and {@link BlobDownloadStrategy} implementation which use the local filesystem for storing
 * the payload
 *
 */
public class FileSystemBlobStrategy implements BlobUploadStrategy, BlobDownloadStrategy{

   
    private final BlobTransferPolicy policy;
    private File rootFile;
    
    public FileSystemBlobStrategy(final BlobTransferPolicy policy) throws MalformedURLException, URISyntaxException  {
        this.policy = policy;
        
        createRootFolder();
    }
    
    /**
     * Create the root folder if not exist 
     * 
     * @throws MalformedURLException
     * @throws URISyntaxException
     */
    protected void createRootFolder() throws MalformedURLException, URISyntaxException {
        rootFile = new File(new URL(policy.getUploadUrl()).toURI());
        if (rootFile.exists() == false) {
            rootFile.mkdirs();
        } else if (rootFile.isDirectory() == false) {
            throw new IllegalArgumentException("Given url is not a directory " + rootFile );
        }
    }
    /*
     * (non-Javadoc)
     * @see org.apache.activemq.blob.BlobUploadStrategy#uploadFile(org.apache.activemq.command.ActiveMQBlobMessage, java.io.File)
     */
    public URL uploadFile(ActiveMQBlobMessage message, File file) throws JMSException, IOException {
        return uploadStream(message, new FileInputStream(file));
    }

    /*
     * (non-Javadoc)
     * @see org.apache.activemq.blob.BlobUploadStrategy#uploadStream(org.apache.activemq.command.ActiveMQBlobMessage, java.io.InputStream)
     */
    public URL uploadStream(ActiveMQBlobMessage message, InputStream in) throws JMSException, IOException {
        File f = getFile(message);
        FileOutputStream out = new FileOutputStream(f);
        byte[] buffer = new byte[policy.getBufferSize()];
        for (int c = in.read(buffer); c != -1; c = in.read(buffer)) {
            out.write(buffer, 0, c);
            out.flush();
        }
        out.flush();
        out.close();
        // File.toURL() is deprecated
        return f.toURI().toURL();
    }

    /*
     * (non-Javadoc)
     * @see org.apache.activemq.blob.BlobDownloadStrategy#deleteFile(org.apache.activemq.command.ActiveMQBlobMessage)
     */
    public void deleteFile(ActiveMQBlobMessage message) throws IOException, JMSException {
        File f = getFile(message);
        if (f.exists()) {
            if (f.delete() == false) throw new IOException("Unable to delete file " + f);
        }
    }

    /**
     * Returns a {@link FileInputStream} for the give {@link ActiveMQBlobMessage}
     */
    public InputStream getInputStream(ActiveMQBlobMessage message) throws IOException, JMSException {
        return new FileInputStream(getFile(message));
    }

    
    /**
     * Return the {@link File} for the {@link ActiveMQBlobMessage}. 
     * 
     * @param message
     * @return file
     * @throws JMSException
     * @throws IOException 
     */
    protected File getFile(ActiveMQBlobMessage message) throws JMSException, IOException {
    	if (message.getURL() != null) {
    		try {
				return new File(message.getURL().toURI());
			} catch (URISyntaxException e) {
                                IOException ioe = new IOException("Unable to open file for message " + message);
                                ioe.initCause(e);
			}
    	}
        //replace all : with _ to make windows more happy
        String fileName = message.getJMSMessageID().replaceAll(":", "_"); 
        return new File(rootFile, fileName);        
        
    }
}

Other ActiveMQ examples (source code examples)

Here is a short list of links related to this ActiveMQ FileSystemBlobStrategy.java source code file:

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