HashThread.java

package net.vhati.modmanager.core;

import java.io.File;
import java.io.FileInputStream;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

import net.vhati.ftldat.FTLDat;
import net.vhati.modmanager.core.HashObserver;

import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;


/**
 * A thread to calculate MD5 hashes of files in the background.
 *
 * As each file is hashed, a class implementing HashObserver is notified.
 * Note: The callback on that class needs to be thread-safe.
 */
public class HashThread extends Thread {

	private static final Logger log = LogManager.getLogger(HashThread.class);

	private List<File> fileList = new ArrayList<File>();
	private HashObserver hashObserver = null;


	public HashThread( File[] files, HashObserver hashObserver ) {
		this.fileList.addAll( Arrays.asList(files) );
		this.hashObserver = hashObserver;
	}


	public void run() {
		for ( File f : fileList ) {
			String hash = calcFileMD5( f );
			if ( hash != null ) {
				hashObserver.hashCalculated( f, hash );
			}
		}

		log.info( "Background hashing finished." );
		hashObserver.hashingEnded();
	}


	private String calcFileMD5( File f ) {
		String result = null;
		try {
			result = FTLDat.calcFileMD5( f );
		}
		catch ( Exception e ) {
			log.error( "Error while calculating hash for file: "+ f.getPath(), e );
		}
		return result;
	}
}