FileLogger.java

FileLogger.java

import android.util.SparseArray;

import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.PrintWriter;
import java.io.Writer;
import java.text.SimpleDateFormat;
import java.util.Date;

import static android.util.Log.ASSERT;
import static android.util.Log.DEBUG;
import static android.util.Log.ERROR;
import static android.util.Log.INFO;
import static android.util.Log.VERBOSE;
import static android.util.Log.WARN;


public class FileLogger {
    private static final SparseArray<String> PRIORITY_TAG_MAP = initTagMap();
    private static final SimpleDateFormat mDateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss.SSS");

    private String mFilePath;
    private PrintWriter mWriter = null;

    public FileLogger(String filePath) {
        mFilePath = filePath;
    }

    public synchronized void close() {
        mFilePath = null;
    }

    public void v(String tag, String message) {
        printlnImpl(VERBOSE, tag, message, null);
    }
    public void v(String tag, String message, Throwable tr) {
        printlnImpl(VERBOSE, tag, message, tr);
    }

    public void d(String tag, String message) {
        printlnImpl(DEBUG, tag, message, null);
    }
    public void d(String tag, String message, Throwable tr) {
        printlnImpl(DEBUG, tag, message, tr);
    }

    public void i(String tag, String message) {
        printlnImpl(INFO, tag, message, null);
    }
    public void i(String tag, String message, Throwable tr) {
        printlnImpl(INFO, tag, message, tr);
    }

    public void w(String tag, String message, Throwable tr) {
        printlnImpl(WARN, tag, message, tr);
    }
    public void w(String tag, String message) {
        printlnImpl(WARN, tag, message, null);
    }

    public void e(String tag, String message) {
        printlnImpl(ERROR, tag, message, null);
    }
    public void e(String tag, String message, Throwable tr) {
        printlnImpl(ERROR, tag, message, tr);
    }

    public void wtf(String tag, String message) {
        printlnImpl(ASSERT, tag, message, null);
    }
    public void wtf(String tag, String message, Throwable tr) {
        printlnImpl(ASSERT, tag, message, tr);
    }

    private synchronized void printlnImpl(int priority, String tag, String message, Throwable tr) {
        Writer writer = getWriter();
        if( writer != null ) {
            mWriter.format("%s %s %s: %s",
                    mDateFormat.format(new Date()),
                    PRIORITY_TAG_MAP.get(priority),
                    tag,
                    message
            );

            if( tr != null ) {
                tr.printStackTrace(mWriter);
            }

            mWriter.print("\n");
            mWriter.flush();
        }
    }

    private synchronized PrintWriter getWriter() {
        if( mWriter == null && mFilePath != null ) {
            try {
                mWriter = new PrintWriter(new FileOutputStream(mFilePath, true));
            } catch (FileNotFoundException e) {
                e.printStackTrace();
            }
        }
        return mWriter;
    }

    private static SparseArray<String> initTagMap() {
        SparseArray<String> map = new SparseArray<String>();
        map.append(VERBOSE, "V");
        map.append(DEBUG, "D");
        map.append(INFO, "I");
        map.append(ERROR, "E");
        map.append(ASSERT, "WTF");
        return map;
    }
}