package org.paneris.bibliomania.fti;
   
   import java.io.IOException;
   import java.io.OutputStream;
   /** 
    * A family of classes to pack numbers into as small a size as possible. 
    * Need to know: http://docs.oracle.com/javase/tutorial/java/nutsandbolts/op3.html
    * 
    * @author williamc
   * @since 2000-05-22
   */
  public abstract class Packer {
    
    /** Unsigned int from byte. */
    public static int uint(byte b) {
      return b >= 0 ? b : 256 + b;
    }
  
    private int numberLength;
    private int numberMax;
  
    /** 
     * 
     * @param numberLength number of bytes
     * @param numberMax maximum representable
     */
    protected Packer(int numberLength, int numberMax) {
      this.numberLength = numberLength;
      this.numberMax = numberMax;
    }
  
    public final int numberLength() {
      return numberLength;
    }
  
    public final int numberMax() {
      return numberMax;
    }
  
    public abstract int number(byte[] bytes, int off);
  
    public abstract Packer bigger();
  
    public abstract void write(OutputStream os, int number) throws IOException;
  }