/*
* 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.oodt.product.handlers.ofsn;
//JDK imports
import java.io.ByteArrayInputStream;
import java.io.File;
import java.io.IOException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Properties;
//APACHE imports
import org.apache.commons.codec.binary.Hex;
import org.apache.commons.io.FileUtils;
//OODT imports
import org.apache.oodt.product.ProductException;
/**
*
* A {@link OFSNGetHandler} to perform an MD5 for a file on the server side.
*
* @author mattmann
* @version $Revision$
*
*/
public class MD5GetHandler implements OFSNGetHandler {
private MessageDigest md = null;
public MD5GetHandler() throws InstantiationException {
try {
this.md = MessageDigest.getInstance("MD5");
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
throw new InstantiationException(e.getMessage());
}
}
/*
* (non-Javadoc)
*
* @see
* org.apache.oodt.product.handlers.ofsn.OFSNListHandler#configure(java.
* util.Properties)
*/
public void configure(Properties conf) {
// TODO Auto-generated method stub
}
/*
* (non-Javadoc)
*
* @see
* org.apache.oodt.product.handlers.ofsn.OFSNGetHandler#retrieveChunk(java
* .lang.String, long, int)
*/
public byte[] retrieveChunk(String filepath, long offset, int length)
throws ProductException {
try {
String hash = this.hashData(FileUtils.readFileToByteArray(new File(
filepath)));
byte[] retBytes = new byte[length];
byte[] hashBytes = hash.getBytes();
ByteArrayInputStream is = new ByteArrayInputStream(hashBytes);
is.skip(offset);
is.read(retBytes, 0, length);
return retBytes;
} catch (IOException e) {
e.printStackTrace();
throw new ProductException("Error reading bytes from file: [" + filepath
+ "] MD5: Message: " + e.getMessage());
}
}
/*
* (non-Javadoc)
*
* @see
* org.apache.oodt.product.handlers.ofsn.OFSNGetHandler#sizeOf(java.lang
* .String)
*/
public long sizeOf(String filepath) {
try {
String hash = this.hashData(FileUtils.readFileToByteArray(new File(
filepath)));
return hash.getBytes().length;
} catch (IOException e) {
e.printStackTrace();
return -1;
}
}
/**
* Use this method ot generate a test MD5 of a provide {@link File} specified
* in args[0].
*
* @param args
* Only need to specify 1 arg, the full path to the {@link File} to
* MD5.
* @throws Exception
* If any error occurs.
*/
public static void main(String[] args) throws Exception {
if (args.length != 1) {
System.err.println("MD5GetHandler <file>");
System.exit(1);
}
String filepath = args[0];
String hashString = new MD5GetHandler().hashData(FileUtils
.readFileToByteArray(new File(filepath)));
System.out.println(hashString);
}
private String hashData(byte[] dataToHash) {
this.md.update(dataToHash, 0, dataToHash.length);
byte[] hash = this.md.digest();
return new String(Hex.encodeHex(hash));
}
}