gistfile1.txt

import java.io.IOException;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.Map;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class BF {
	private interface Visitor 
	{
		void visit (Character character);
		void visit (Function function);
		void visit (CallFunction functionCall);
		void visit (Loop loop);
		void visit (Left left);
		void visit (Right right);
		void visit (Increment increment);
		void visit (Decrement decrement);
		void visit (Number number);
		void visit (Input input);
		void visit (Output output);
		void visit (Program program);
	}
	private interface Node 
	{
		void accept (Visitor v);
	}
	private class Character implements Node
	{
		public String character;
		public Character(String character)
		{
			this.character = character;
		}
		public void accept (Visitor v)
		{
			v.visit(this);
		}
	}
	private class Function implements Node
	{
		public Node body;
		public Function(Node body)
		{
			this.body = body;
		}
		public void accept(Visitor v)
		{
			v.visit(this);
		}
	}
	private class CallFunction implements Node
	{
		public void accept(Visitor v)
		{
			v.visit(this);
		}
	}
	private class Left implements Node 
	{
		public void accept (Visitor v) 
		{
			v.visit(this);
		}
	}
	private class Right implements Node 
	{
		public void accept (Visitor v) 
		{
			v.visit(this);
		}
	}
	private class Increment implements Node 
	{
		public void accept (Visitor v) 
		{
			v.visit(this);
		}
	}
	private class Decrement implements Node 
	{
		public void accept (Visitor v) 
		{
			v.visit(this);
		}
	}
	private class Input implements Node 
	{
		public void accept (Visitor v) 
		{
			v.visit(this);
		}
	}
	private class Output implements Node 
	{
		public void accept (Visitor v) 
		{
			v.visit(this);
		}
	}
	private class Number implements Node
	{
		public int iterations;
		public Node command;
		public Number(int number, Node command)
		{
			iterations = number;
			this.command = command;
		}
		public void accept(Visitor v)
		{
			v.visit(this);
		}
	}
	private class Sequence implements Node 
	{
		private LinkedList<Node> children;
		public Sequence() 
		{
			children = new LinkedList<Node>();
		}
		public void accept (Visitor v) 
		{
			for (Node child : children) 
			{
				child.accept(v);
			}
		}
		public void add (Node instruction) 
		{
			children.add(instruction);
		}
	}
	private class Loop implements Node 
	{
		public Node body;
		public Loop (Node body) 
		{
			this.body = body;
		}
		public void accept (Visitor v) 
		{
			v.visit (this);
		}
	}
	public static class Program implements Node 
	{
		public Node body;
		public Program (Node body) 
		{
			this.body = body;
		}
		public void accept(Visitor v) 
		{
			v.visit (this);
		}
	}
	private int i = 0;
	private Sequence doParse (String str) 
	{
		Sequence seq = new Sequence();
		char c;
		while (i < str.length ()) 
		{
			c = str.charAt (i);
			if (c == '<') seq.add (new Left ());
			else if (c == '>') seq.add (new Right ());
			else if (c == '+') seq.add (new Increment ());
			else if (c == '-') seq.add (new Decrement ());
			else if (c == '.') seq.add (new Output ());
			else if (c == ',') seq.add (new Input ());
			else if (c == ':') seq.add (new CallFunction());
			else if (c == '[')
			{
				i++;
				seq.add (new Loop (doParse (str)));
			}
			else if(c == '(')
			{
				i++;
				seq.add (new Function(doParse(str)));
			}
			else if(str.charAt(i) >= 48 && str.charAt(i) <= 57)
			{
				Pattern p = Pattern.compile("\\d+");
				Matcher m = p.matcher(str.substring(i)); 
				m.find();
				String numString = m.group();
				i += numString.length();
				int num = Integer.parseInt(numString);
				int temp = i;
				i = 0;
				Node node = doParse(""+str.charAt(temp));
				i = temp;
				seq.add(new Number(num,node));
			}
			else if (c == ']') return seq;
			else if (c == ')') return seq;
			else if (c == '"')
			{
				i++;
				String characters = "";
				while(str.charAt(i) != '"')
					characters += str.charAt(i++);
				seq.add(new Character(characters));
			}
			i++;
		}
		return seq;
	}
	public static Program parse (String str) 
	{
		return new Program (new BF().doParse(str));
	}
	public static void main(String[] args) 
	{
		Node ascii = BF.parse("(++++++++++<[>+>+<<-]>>[<<+>>-])>::::::::::::::<<<<<<<--------.>>>---------.+++++++..>---------.<<<<<<<------.<--------.>>>>>---.>>>.+++.<.--------.<<<<<<<+.");
		ascii.accept(new BF.CompilerVisitor());
		System.out.println();
		Node name = BF.parse("77+.>105+.>107+.>101+.>32+.>77+.>117+.>101+.>115+.>99+.>104+.>");
		name.accept(new BF.InterpreterVisitor());
		System.out.println();
	}
	public static class PrintVisitor implements Visitor 
	{
		public void visit (Left n) { System.out.print('<'); }
		public void visit (Right n) { System.out.print('>'); }
		public void visit (Increment n) { System.out.print('+'); }
		public void visit (Decrement n) { System.out.print('-'); }
		public void visit (Input n) { System.out.print(','); }
		public void visit (Output n) { System.out.print('.'); }
		public void visit (Loop n) { System.out.print('['); n.body.accept(this); System.out.print(']'); }
		public void visit (Program n) { n.body.accept(this); }
		public void visit(Character n) {System.out.print("\""+n.character+"\"");}
		public void visit(Number n) {System.out.print(""+n.iterations);n.command.accept(this);}
		public void visit(Function function) {System.out.print("("); function.body.accept(this); System.out.print(")");}
		public void visit(CallFunction functionCall) {System.out.print(":");}
	}
	public static void displayByteArray(byte[] array, int pointer)
	{
		for(int i = 0;i < 100;i++)
		{
			for(int j = 0;j < 300;j++)
			{
				if(pointer == (i*300)+j)
					System.out.print(">");
				else
					System.out.print(" ");
				System.out.print(""+array[(i*300)+j]);
			}
			System.out.println();
		}
		System.out.println("===================================");
	}
	public static class CompilerVisitor implements Visitor
	{
		int loopNumber;
		private Map<Byte,Function> functions;
		private byte[] array;
		private int pointer;
		public void visit(Character character) 
		{
			System.out.println("string=\""+character.character+"\";");
			System.out.println("for(int i = 0;i < string.length();i++){");
			System.out.println("char c = string.charAt(i);");
			System.out.println("array[pointer] = (byte)c;");
			System.out.println("pointer++;");
			System.out.println("array[pointer] = 0;");
			System.out.println("}");
		}
		public void visit(Function function) 
		{
			System.out.println("procedures[array[pointer]] = new Procedure() {public void execute() {");
			function.body.accept(this);
			System.out.println("}};");
		}
		public void visit(CallFunction functionCall) 
		{
			System.out.println("procedures[array[pointer]].execute();");
		}
		public void visit(Loop loop) 
		{
			System.out.println("while(array[pointer] != 0){");
			loop.body.accept(this);
			System.out.println("}");
		}
		public void visit(Left left) 
		{
			System.out.println("pointer--;");
		}
		public void visit(Right right) 
		{
			System.out.println("pointer++;");
		}
		public void visit(Increment increment) 
		{
			System.out.println("array[pointer]++;");
		}
		public void visit(Decrement decrement) 
		{
			System.out.println("array[pointer]--;");
		}
		public void visit(Input input)
		{
			System.out.println("array[pointer] = (byte) System.in.read();");
		}
		public void visit(Output output) 
		{
			System.out.println("System.out.print(\"\"+(char)array[pointer]);");
		}
		public void visit(Program program) 
		{
			loopNumber = 0;
			array = new byte[30000];
			pointer = 0;
			functions = new HashMap<Byte,Function>();
			System.out.println("class Prog {");
			System.out.println("public interface Procedure {");
			System.out.println("    void execute();");
			System.out.println("}");
			System.out.println("private static Procedure[] procedures;");
			System.out.println("private static byte[] array;");
			System.out.println("private static int pointer;");
			System.out.println("private static String string;");
			System.out.println("public static void main(String[] args){");
			System.out.println("array = new byte[30000];");
			System.out.println("pointer = 0;");
			System.out.println("procedures = new Procedure[256];");
			program.body.accept(this);
			System.out.println("}}");
		}
		public void visit(Number number) 
		{
			for(int i = 0;i < number.iterations;i++)
				number.command.accept(this);
		}
	}
	public static class InterpreterVisitor implements Visitor 
	{
		private byte[] array;
		private int pointer;
		private Map<Byte,Function> functions;

		public void visit (Left n) { pointer--; }
		public void visit (Right n) { pointer++; }
		public void visit (Increment n) { array[pointer]++; }
		public void visit (Decrement n) { array[pointer]--; }
		public void visit (Input n) 
		{
			try 
			{
				array[pointer] = (byte) System.in.read();
			} 
			catch (IOException e) 
			{

			} 
		}
		public void visit (Output n) 
		{ 
			System.out.print((char)array[pointer]); 
		}
		public void visit (Loop n) 
		{
			while (array[pointer] != 0) 
			{
				n.body.accept(this);
			}
		}
		public void visit (Program n) 
		{
			array = new byte[30000];
			pointer = 0;
			functions = new HashMap<Byte,Function>();
			n.body.accept(this);
		}
		public void visit(Character n) 
		{
			for(int i = 0;i < n.character.length();i++)
			{
				array[pointer] = (byte)n.character.charAt(i);
				pointer++;
				array[pointer] = 0;
			}
		}
		public void visit(Function n)
		{
			functions.put(Byte.parseByte(""+(array[pointer])), n);
		}
		public void visit(CallFunction n) 
		{
			Function function = functions.get(Byte.parseByte(""+array[pointer]));
			if(function != null)
				function.body.accept(this);
		}
		public void visit(Number number) 
		{
			for(int i = 0;i < number.iterations;i++)
				number.command.accept(this);
		}
	}

	public static class AnimationVisitor implements Visitor 
	{
		private byte[] array;
		private int pointer;
		private Map<Byte,Function> functions;

		public void visit (Left n) { pointer--; BF.displayByteArray(array,pointer); }
		public void visit (Right n) { pointer++; BF.displayByteArray(array,pointer); }
		public void visit (Increment n) { array[pointer]++; BF.displayByteArray(array,pointer); }
		public void visit (Decrement n) { array[pointer]--; BF.displayByteArray(array,pointer); }
		public void visit (Input n) 
		{
			try 
			{
				array[pointer] = (byte) System.in.read();
			} 
			catch (IOException e) 
			{

			}
			BF.displayByteArray(array,pointer); 
		}
		public void visit (Output n) 
		{ 
			System.out.print((char)array[pointer]); 
			BF.displayByteArray(array,pointer); 
		}
		public void visit (Loop n) 
		{
			while (array[pointer] != 0) 
			{
				n.body.accept(this);
			}
		}
		public void visit (Program n) 
		{
			array = new byte[30000];
			pointer = 0;
			functions = new HashMap<Byte,Function>();
			n.body.accept(this);
		}
		public void visit(Character n) 
		{
			for(int i = 0;i < n.character.length();i++)
			{
				array[pointer] = (byte)n.character.charAt(i);
				pointer++;
				array[pointer] = 0;
				BF.displayByteArray(array,pointer); 
			}
		}
		public void visit(Function n)
		{
			functions.put(Byte.parseByte(""+(array[pointer])), n);
		}
		public void visit(CallFunction n) 
		{
			Function function = functions.get(Byte.parseByte(""+array[pointer]));
			if(function != null)
				function.body.accept(this);
		}
		public void visit(Number number) 
		{
			for(int i = 0;i < number.iterations;i++)
				number.command.accept(this);
		}
	}
}