Tiny Brainfuck Interpreter Written in Java

Brainfuck.java

import java.util.*;
public class Brainfuck {
    private Scanner sc = new Scanner(System.in);
    private final int LENGTH = 65535;
    private byte[] mem = new byte[LENGTH];
    private int dataPointer;

    public void interpret(String code) {
        int l = 0;
        for(int i = 0; i < code.length(); i++) {
            if(code.charAt(i) == '>') {
                dataPointer = (dataPointer == LENGTH-1) ? 0 : dataPointer + 1;
            } else if(code.charAt(i) == '<') {
                dataPointer = (dataPointer == 0) ? LENGTH-1 : dataPointer - 1;
            } else if(code.charAt(i) == '+') {
                mem[dataPointer]++;
            } else if(code.charAt(i) == '-') {
                mem[dataPointer]--;
            } else if(code.charAt(i) == '.') {
                System.out.print((char) mem[dataPointer]);
            } else if(code.charAt(i) == ',') {
                mem[dataPointer] = (byte) sc.next().charAt(0);
            } else if(code.charAt(i) == '[') {
                if(mem[dataPointer] == 0) {
                    i++;
                    while(l > 0 || code.charAt(i) != ']') {
                        if(code.charAt(i) == '[') l++;
                        if(code.charAt(i) == ']') l--;
                        i++;
                    }
                }
            } else if(code.charAt(i) == ']') {
                if(mem[dataPointer] != 0) {
                    i--;
                    while(l > 0 || code.charAt(i) != '[') {
                        if(code.charAt(i) == ']') l++;
                        if(code.charAt(i) == '[') l--;
                        i--;
                    }
                    i--;
                }
            }
        }
    }

    public static void main(String[] args) {
        new Brainfuck().interpret(args[0]);
    }
}

BrainfuckToJava.java

public class BrainfuckToJava {
	private StringBuilder source;
	private int ident;
	
	public BrainfuckToJava(String code) {
		source = new StringBuilder();
		source.append("import java.util.Scanner;\n");
		source.append("public class BFConverted {\n");
		source.append("\tprivate static int ptr;\n");
		source.append("\tprivate static byte[] mem = new byte[65535];\n");
		source.append("\tprivate static Scanner in = new Scanner(System.in);\n");
		source.append("\tpublic static void main(String[] args) {\n");
		convert(code, source);
		source.append("\t}\n");
		source.append("}\n");
		System.out.println(source.toString());
	}
	
	private void convert(String code, StringBuilder source) {
		for(int i = 0; i < code.length(); i++) {
			for(int t = 0; t < ident; t++) source.append('\t');
			switch(code.charAt(i)) {
				case '>': source.append("\t\tptr++;\n"); break;
				case '<': source.append("\t\tptr--;\n"); break;
				case '+': source.append("\t\tmem[ptr]++;\n"); break;
				case '-': source.append("\t\tmem[ptr]--;\n"); break;
				case '.': source.append("\t\tSystem.out.print((char) mem[ptr]);\n"); break;
				case ',': source.append("\t\tmem[ptr] = (byte) in.next().charAt(0);\n"); break;
				case '[': source.append("\t\twhile(mem[ptr] != 0) {\n"); ident++; break;
				case ']': source.append("\t\t}\n"); break;
				default: continue;
			}
			if(i+1 < code.length() && code.charAt(i+1) == ']') ident--;
		}
	}
	
	public static void main(String[] args) {
		new BrainfuckToJava(args[0]);
	}
}

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