-----------------------------------

Aziz

Mon Jun 27, 2005 1:34 am


[Source Code] HighScoreList class

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Hey I wrote this yesterday and today. Got the idea from my Turing module, but this ones kinda different :P Java makes it easy. Tell me what you think and what I could do to make it better. I'll be posting a test class up soon but right now I NEED SLEEEEEEEEEEP *DROOL* Goodnight :)

/* The "HighscoreList" class
 * Creates a highscore list for a game
 * with names and scores.
 * Scores can be added (automatticaly sorted)
 * You can get an array of scores, or a single score
 * Also different methods like clearing the list, getting the size of it, etc.
 */
 
 import java.io.*;
 
 public class HighScoreList
 {
 	//Default size and file name constants
 	protected final int SIZE = 5;
 	protected final String FILE_NAME = "highscore.dat";
 	
 	//Size of the highscore list (number of entries)
 	protected int size;
 	
 	//The file name
 	protected String fileName;
 	
 	//Scores and names arrays
 	protected int scores[];
 	protected String names[];
 	
 	////////////////
 	//CONSTRUCTORS//
 	////////////////
 	
 	//Constructor that set size and filename to defaults
 	public HighScoreList() throws IOException
 	{
 		//Set size and file name
 		size = SIZE;
 		fileName = FILE_NAME;
 		
 		//Set size of scores and names array;
 		scores = new int[size + 1];
 		names = new String[size + 1];
 		
 		//File object
 		File file = new File(fileName);
 		
 		//Checks to see if the file specified is an already existing file
 		//Or if we need to make a new one.
 		if (file.exists())
 		{
 			//Get the names and scores into the lists
 			readScores();
 		} else
 		{
	 		//Create file
	 		createFile();
	 		
	 		//Set all the objects' scores arrays to blanks
	 		for (int i = 0; i < scores.length - 1; i++)
	 		{
	 			scores[i] = 0;
	 			names[i] = "---";
	 		}
 		}
 	}
 	
 	//Constructor that sets size to specified and filename to default
 	//Will only read the first [dSize] scores 
 	public HighScoreList(int dSize) throws IOException
 	{
 		//Set size and file name
 		size = dSize;
 		fileName = FILE_NAME;
 		
 		//Set size of scores and names array;
 		scores = new int[size + 1];
 		names = new String[size + 1];
 		
 		//File object
 		File file = new File(fileName);
 		
 		//Checks to see if the file specified is an already existing file
 		//Or if we need to make a new one.
 		if (file.exists())
 		{
 			//Get the names and scores into the lists
 			readScores();
 		} else
 		{
	 		//Create file
	 		createFile();
	 		
	 		//Set all the objects' scores arrays to blanks
	 		for (int i = 0; i < scores.length - 1; i++)
	 		{
	 			scores[i] = 0;
	 			names[i] = "---";
	 		}
 		}
 	}
 	
 	//Constructor that sets filename to specified and size to default
 	public HighScoreList(String dFileName) throws IOException
 	{
 		//Set size and file name
 		size = SIZE;
 		fileName = dFileName;
 		
 		//Set size of scores and names array;
 		scores = new int[size + 1];
 		names = new String[size + 1];
 		
 		//File object
 		File file = new File(fileName);
 		
 		//Checks to see if the file specified is an already existing file
 		//Or if we need to make a new one.
 		if (file.exists())
 		{
 			//Get the names and scores into the lists
 			readScores();
 		} else
 		{
	 		//Create file
	 		createFile();
	 		
	 		//Set all the objects' scores arrays to blanks
	 		for (int i = 0; i < scores.length - 1; i++)
	 		{
	 			scores[i] = 0;
	 			names[i] = "---";
	 		}
 		}
 	}
 	
 	//Constructor that set size and filename to specified
 	//Will only read the first [dSize] scores
 	public HighScoreList(int dSize, String dFileName2) throws IOException
 	{
 		//Set size and file name
 		size = dSize;
 		fileName = dFileName2;
 		
 		//Set size of scores and names array;
 		scores = new int[size + 1];
 		names = new String[size + 1];
 		
 		//File object
 		File file = new File(fileName);
 		
 		//Checks to see if the file specified is an already existing file
 		//Or if we need to make a new one.
 		if (file.exists())
 		{
 			//Get the names and scores into the lists
 			readScores();
 		} else
 		{
	 		//Create file
	 		createFile();
	 		
	 		//Set all the objects' scores arrays to blanks
	 		for (int i = 0; i < scores.length - 1; i++)
	 		{
	 			scores[i] = 0;
	 			names[i] = "---";
	 		}
 		}
 	}
 	
 	/////////////
 	//PROTECTED//
 	/////////////
 	
 	//Bubble Sort (sorts according to scores and places names with)
 	protected void sort()
 	{
 		//Temporary variables
 		int tempScore;			//Temporary score
 		String tempName;		//Temporary name
 		
 		//Sorted flag
 		boolean sorted = true;
 		
 		//Continue sorted until the list is sorted
 		do
 		{
 			//Reset flag
 			sorted = true;
 			
 			//Check and sort
 			for (int i = 0; i < scores.length - 1; i++)
 			{
 				if (scores[i] < scores[i+1])
 				{
 					//Swap scores
 					tempScore = scores[i+1];
 					scores[i+1] = scores[i];
 					scores[i] = tempScore;
 					
 					//Swap names
 					tempName = names[i+1];
 					names[i+1] = names[i];
 					names[i] = tempName;
 					
 					//Flag not sorted
 					sorted = false;
 				}
 			}
 			
 		} while (!sorted);	
 	}
 	
 	//Creates the highscore file, settings names to "---" and scores to 0
 	protected void createFile() throws IOException
 	{
 		//New PrintWriter to output to highscore file
 		PrintWriter output = new PrintWriter(new FileWriter(fileName));
 		
 		//Write as many blank entries as needed
 		for (int i = 0; i < scores.length - 1; i++)
 		{
 			output.println("---" + "#" + 0 + "$");
 		}
 		
 		//Close stream
 		output.close();
 	}
 	
 	//Reads the scores to local array
 	protected void readScores() throws IOException
 	{
 		//New BufferedReader to get the scores from the highscore list
 		BufferedReader input = new BufferedReader(new FileReader(fileName));
 		
 		//Temporary input line
 		String tempLine;
 		char tempChLine[]; //Array of characters
 		
 		//Temporary score string
 		String scoreStr;
 		
 		//Counting variable
 		int j;
 		
 		//Read first line
 		tempLine = input.readLine();
 		
 		//Write as many blank entries as needed
 		for (int i = 0; i < scores.length - 1; i++)
 		{
 			//Set the array of characters to line read from file
 			tempChLine = tempLine.toCharArray();
 			
 			//Clear string
 			scoreStr = "";
 			names[i] = "";
 			
 			//Reset counting variable
 			j = 0;
 			
 			//Add the characters to name until marker #
 			while (tempChLine[j] != '#')
 			{
 				names[i] += tempChLine[j];
 				j++;
 			}
 			
 			j++;
 			
 			//Add the characters to score string until marker $
 			while (tempChLine[j] != '$')
 			{
 				scoreStr += tempChLine[j];
 				j++;
 			}
 			
 			//Add integer value of scoreStr to score
 			scores[i] = Integer.parseInt(scoreStr);
 			
 			//Read next line
 			tempLine = input.readLine();
 		}
 		
 		//Close stream
 		input.close();	
 	}
 	
 	//Writes list of scores to file
 	protected void writeScores() throws IOException
 	{
 		//New PrintWriter to output to highscore file
 		PrintWriter output = new PrintWriter(new FileWriter(fileName));
 		
 		//Write the scores
 		for (int i = 0; i < scores.length - 1; i++)
 		{
 			output.println(names[i] + "#" + scores[i] + "$");
 		}
 		
 		//Close stream
 		output.close();
 	}
 	
 	//////////
 	//PUBLIC//
 	//////////
 	
 	//Adds the specified score (w/ name) to the list and writes it to file
 	public void addScore(String name, int score) throws IOException
 	{
 		//Add the score and its name to end of array
		names[size] = name;
		scores[size] = score;
		
		//Sorts them in
		sort();
 	}
 	
 	//Clears the highscore file (basically same as createFile(), but user can user it
 	public void clearList() throws IOException
 	{
 		//New PrintWriter to output to highscore file
 		PrintWriter output = new PrintWriter(new FileWriter(fileName));
 		
 		//Write as many blank entries as needed
 		for (int i = 0; i < scores.length - 1; i++)
 		{
 			output.println("---" + "#" + 0 + "$");
 		}
 		
 		//Close stream
 		output.close();
 	}
 	
 	//Returns the size of the highscore list
 	public int getSize()
 	{
 		return size;
 	}
 	
 	//Returns the list of names
 	public String[] getNames()
 	{
 		return names;
 	} 	
 	
 	//Returns the list of scores
 	public int[] getScores()
 	{
 		return scores;
 	}
 	
 	//Returns top score holder's name
 	public String getTopScoreHolder()
 	{
 		return names[1];
 	}
 	
 	//Returns top score holder's score
 	public int getTopScore()
 	{
 		return scores[1];
 	}
 	
 	//Returns specified highscore holder's name
 	//(returns error msg if value over list size)
 	public String getScoreHolder(int place)
 	{
 		if (place < size)
 		{
 			return names[place];
 		} else 
 		{
 			return "Invalid place";
 		}
 	}
 	
 	//Returns specified highscore holder's score
 	//(returns -1 if value over list size)
 	public int getScore(int place)
 	{
 		if (place < size)
 		{
 			return scores[place];
 		} else 
 		{
 			return -1;
 		}
 	}
 }


-----------------------------------

wtd

Mon Jun 27, 2005 1:40 am



-----------------------------------

Now rewrite it much shorter by subclassing something like ArrayList.  :)


-----------------------------------

Aziz

Mon Jun 27, 2005 9:37 am



-----------------------------------

If I knew how and new what subclassing mean I would  :lol:
*Still java n00b*


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wtd

Mon Jun 27, 2005 2:37 pm



-----------------------------------

I'm talking about inheritance.  "Is a" relationships.  Code reuse.  :)

You're creating a list class, right?  So each object of that class is going to be a list.  Well, we already have basic list classes, so why not inherit from those and get all of the list functionality "for free"?

Consider a simple example: my classic Name class.

class Name 
{
   private String first, last;

   public Name(String f, String l)
   {
      first = f;
      last = l;
   }

   public String getFirst() { return first; }
   public String getLast() { return last; }

   public String fullName()
   {
      return first + " " + last;
   }
}

Now, what if I want a name class that has a title?  We'll call it "FormalName".  Well, I would copy and paste and write an entirely new class.

class Name 
{
   private String title, first, last;

   public Name(String t, String f, String l)
   {
      title = t;
      first = f;
      last = l;
   }

   public String getTitle() { return title; }
   public String getFirst() { return first; }
   public String getLast() { return last; }

   public String fullName()
   {
      return title + " " + first + " " + last;
   }
}

Or, I could use inheritance and make FormalName a subclass of Name.

class FormalName extends Name
{
   private String title;

   public FormalName(String t, String f, String l)
   {
      super(f, l);
      title = t;
   }

   public String getTitle() { return title; }

   public String fullName()
   {
      return title + " " + super.fullName();
   }
}

Now, to take this a bit further...

class DoctorsName extends FormalName
{
   public FormalName(String f, String l)
   {
      super("Dr.", f, l);
   }
}

And now since a FormalName is a Name, anywhere I have a method that takes a Name as a parameter, I can give it a FormalName, or a DoctorsName.


-----------------------------------

Aziz

Mon Jun 27, 2005 3:03 pm



-----------------------------------

Would that be possible for this? My highscore list has 2 lists...names and scores, or is there another way, oh great Dark Master?


-----------------------------------

wtd

Mon Jun 27, 2005 3:15 pm



-----------------------------------

Presumably each score is connected to a name.  Create a HighScoreRecord class.

(Java 1.4.2)

class HighScoreRecord implements Comparable
{
   private String name;
   private int score;

   public HighScoreRecord(String n, int s)
   {
      name = n;
      score = s;
   }

   public String getName() { return name; }
   public int getScore() { return score; }

   public int compareTo(Object o)
   {
      HighScoreRecord other = (HighScoreRecord)o;

      int scoreComparison = new Integer(score).compareTo(new Integer(other.getScore()));
      int nameComparison = name.compareTo(other.getName());

      if (scoreComparison == 0)
      {
         return nameComparison;
      }
      else
      {
         return scoreComparison;
      }
   }
}

Now you can just have a single list of those.  :)


-----------------------------------

Aziz

Mon Jun 27, 2005 3:41 pm



-----------------------------------

Awesome, I'm going to try that later. And actually try to understand it, instead of just copy and paste it. But not right now. I'm going to go play some Xbox. Thanks a bunch.

Oh and one more question. How do you get the java code tags? Instead of just:


     !CODE!

Thanks :)


-----------------------------------

wtd

Mon Jun 27, 2005 3:50 pm



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[syntax="java"]blah blah blah[/syntax]