import java.io.*;
import java.lang.*;

/**
  * Light superclass
  *
  * Each type of light must extend and implement this class.
  * @author Anthony Steed
  * @version 1.0
  */

public abstract class Light {

  /** 
    * Holds the colour of this light
    */
  public Colour Intensity;
    
  /**
    * Read the light from the given source
    * @param is the source to read from
    * @exception java.io.IOException
    * if the light can not be read
    * @exception java.io.NumberFormatException
    * if there a number format error is encountered
    */
  abstract public void read(SceneReader is) 
    throws IOException, NumberFormatException;

  /**
    * Write the light to the given destination
    * @param os  the destination to write to
    * @exception java.io.IOException
    * if the write fails.
    */
  abstract public void write(SceneWriter os) throws IOException;

  /** 
    * Print a human readable version of the light definition to the
    * given destination
    * @param os  the destination to write to
    * @exception java.io.IOException
    * if the write fails.  */
  abstract public void print(SceneWriter os) throws IOException;
}