Sistema de log criado em Java

LogSystem

package logproject;

import java.io.BufferedWriter;
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;

public final class LogSystem implements AutoCloseable {

    private static LogSystem instance;
    private final StringBuilder data;
    private File file;
    private FileWriter out;
    private BufferedWriter buffer;
    private static final String SEPARATOR = "\t";
    private static final String END_OF_LINE = "\r\n";
    private static final String DEFAULT_FILE_NAME = "log.txt";
    private static final int EMPTY = 0;

    private LogSystem() {
        setFileName(DEFAULT_FILE_NAME);
        data = new StringBuilder();
    }

    public static synchronized LogSystem getInstance() {
        if (instance == null) {
            instance = new LogSystem();
        }

        return instance;
    }

    public LogSystem setFileName(String pathName) {
        file = new File(pathName);
        return this;
    }

    public LogSystem open() {
        return open(false);
    }

    public LogSystem open(boolean appendMode) {
        try {
            out = new FileWriter(file, appendMode);
            if (buffer != null) {
                buffer.close();
            }
            buffer = new BufferedWriter(out);
        } catch (IOException ex) {
            ex.printStackTrace();
        }
        return this;
    }

    public LogSystem clear() {
        data.delete(0, data.length());
        return this;
    }

    public LogSystem saveChange() {
        if (data.length() != 0) {
            nextLine();
        }

        try {
            buffer.write(data.toString());
            buffer.flush();
            clear();
        } catch (IOException ex) {
            ex.printStackTrace();
        }

        return this;
    }

    public LogSystem nextLine() {
        data.append(END_OF_LINE);
        return this;
    }

    public LogSystem append(String text) {
        data.append(text).append(SEPARATOR);
        return this;
    }

    public LogSystem append(int text) {
        data.append(text).append(SEPARATOR);
        return this;
    }

    public LogSystem append(float text) {
        data.append(text).append(SEPARATOR);
        return this;
    }

    public LogSystem append(double text) {
        data.append(text).append(SEPARATOR);
        return this;
    }

    public LogSystem append(char text) {
        data.append(text).append(SEPARATOR);
        return this;
    }

    public LogSystem append(boolean text) {
        data.append(text).append(SEPARATOR);
        return this;
    }

    public LogSystem append(long text) {
        data.append(text).append(SEPARATOR);
        return this;
    }

    public LogSystem append(Object text) {
        data.append(text).append(SEPARATOR);
        return this;
    }

    public LogSystem appendLine(String text) {
        data.append(text).append(END_OF_LINE);
        return this;
    }

    public LogSystem appendLine(int text) {
        data.append(text).append(END_OF_LINE);
        return this;
    }

    public LogSystem appendLine(float text) {
        data.append(text).append(END_OF_LINE);
        return this;
    }

    public LogSystem appendLine(double text) {
        data.append(text).append(END_OF_LINE);
        return this;
    }

    public LogSystem appendLine(char text) {
        data.append(text).append(END_OF_LINE);
        return this;
    }

    public LogSystem appendLine(boolean text) {
        data.append(text).append(END_OF_LINE);
        return this;
    }

    public LogSystem appendLine(long text) {
        data.append(text).append(END_OF_LINE);
        return this;
    }

    public LogSystem appendLine(Object text) {
        data.append(text).append(END_OF_LINE);
        return this;
    }

    @Override
    public void close() throws Exception {
        if (buffer != null) {
            buffer.close();
        }
    }
}

Esse esquema de log foi criado para um amigo que precisava tabelar seus dados em um arquivo. Contudo, ainda irei colocar formas de gravar em 3 formatos (TXT, XML, JSON) e também uma forma de log pura com o dia e horário da informação.

Muito obrigado Kleber, é um ótimo script e muito útil