IMD5SumFilter.java

/*
  IMD5SumFilter.java

  (c) 2015 Edward Swartz

  All rights reserved. This program and the accompanying materials
  are made available under the terms of the Eclipse Public License v1.0
  which accompanies this distribution, and is available at
  http://www.eclipse.org/legal/epl-v10.html
 */
package v9t9.common.files;

import java.util.Collection;

import ejs.base.utils.HexUtils;

/**
 * This interface defines which content from a candidate file 
 * is summed to make MD5 matches.
 * 
 * This should define #equals and #hashCode for use in 
 * repeated lookups. 
 * @author ejs
 *
 */
public interface IMD5SumFilter {
	public class FilterSegment {
		public FilterSegment(int offs, int count) {
			this.offset = offs;
			this.length = count;
		}
		public int offset;
		public int length;
		
		@Override
		public String toString() {
			return HexUtils.toHex4(offset) + "+" + HexUtils.toHex4(length);
		}
	}

	/** Get the identifier for referencing the filter */
	String getId();
	
	/** Fill in the segments that should be considered from the given URI */
	void fillSegments(int contentLength, Collection<IMD5SumFilter.FilterSegment> segments);

}