android logUtil

logUtil.java

public class LogUtil {
    private boolean debug;
    private String tag;

    private static final String LOG_FILE_NAME = "jz.log";

    public LogUtil() {
        this(null);
    }

    public LogUtil(String tag) {
        this(true, tag);
    }

    public LogUtil(boolean debug, String tag) {
        this.debug = debug & JZApp.GLOBAL_DEBUG;
        this.tag = tag;
    }

    public void v(String msg) {
        if (debug) {
            String[] m = buildMessage(msg);
            Log.v(m[0], m[1]);
        }
    }

    public void v(String msg, Object... args) {
        if (debug) {
            String[] m = buildMessage(String.format(msg, args));
            Log.v(m[0], m[1]);
        }
    }

    public void v(String msg, Throwable thr) {
        if (debug) {
            String[] m = buildMessage(msg);
            Log.v(m[0], m[1], thr);
        }
    }

    public void d(String msg) {
        if (debug) {
            String[] m = buildMessage(msg);
            Log.d(m[0], m[1]);
        }
    }

    public void d(String msg, Object... args) {
        if (debug) {
            String[] m = buildMessage(String.format(msg, args));
            Log.d(m[0], m[1]);
        }
    }

    public void d(String msg, Throwable thr) {
        if (debug) {
            String[] m = buildMessage(msg);
            Log.d(m[0], m[1], thr);
        }
    }

    public void i(String msg) {
        if (debug) {
            String[] m = buildMessage(msg);
            Log.i(m[0], m[1]);
        }
    }

    public void i(String msg, Object... args) {
        if (debug) {
            String[] m = buildMessage(String.format(msg, args));
            Log.i(m[0], m[1]);
        }
    }

    public void i(String msg, Throwable thr) {
        if (debug) {
            String[] m = buildMessage(msg);
            Log.i(m[0], m[1], thr);
        }
    }

    public void e(String msg) {
        if (debug) {
            String[] m = buildMessage(msg);
            Log.e(m[0], m[1]);
        }
    }

    public void e(String msg, Object... args) {
        if (debug) {
            String[] m = buildMessage(String.format(msg, args));
            Log.e(m[0], m[1]);
        }
    }

    public void e(String msg, Throwable thr) {
        if (debug) {
            String[] m = buildMessage(msg);
            Log.e(m[0], m[1], thr);
        }
    }

    public void w(String msg) {
        if (debug) {
            String[] m = buildMessage(msg);
            Log.w(m[0], m[1]);
        }
    }

    public void w(String msg, Object... args) {
        if (debug) {
            String[] m = buildMessage(String.format(msg, args));
            Log.w(m[0], m[1]);
        }
    }

    public void w(String msg, Throwable thr) {
        if (debug) {
            String[] m = buildMessage(msg);
            Log.w(m[0], m[1], thr);
        }
    }

    public void file(String msg, Throwable thr) {
        if (!debug) {
            return;
        }
        File f = new File(Environment.getExternalStorageDirectory(), LOG_FILE_NAME);
        FileOutputStream fos = null;
        try {
            fos = new FileOutputStream(f, true);
            String fm = new Date().toString() + "\n";
            fos.write(fm.getBytes(Charset.forName("utf-8")));
            thr.printStackTrace(new PrintStream(fos));
            fos.write("\n\n".getBytes());

        } catch (Exception e) {
            e("write file log failed");
            i(msg, thr);
        } finally {
            if (fos != null) {
                try {
                    fos.close();
                } catch (IOException e) {
                    // null
                }
            }
        }
    }

    public void file(String msg, Object... args) {
        if (!debug) {
            return;
        }
        File f = new File(Environment.getExternalStorageDirectory(), LOG_FILE_NAME);
        FileOutputStream fos = null;
        try {
            fos = new FileOutputStream(f, true);
            String fm = new Date().toString() + "\n";
            fos.write(fm.getBytes(Charset.forName("utf-8")));
        } catch (Exception e) {
            e("write file log failed");
            i(msg, args);
        } finally {
            if (fos != null) {
                try {
                    fos.close();
                } catch (IOException e) {
                    // null
                }
            }
        }
    }

    protected String[] buildMessage(String msg) {
        StackTraceElement caller = new Throwable().fillInStackTrace().getStackTrace()[2];
        String msgTag = tag;
        if (TextUtils.isEmpty(tag)) {
            msgTag = caller.getClassName().substring(caller.getClassName().lastIndexOf('.') + 1);
        }
        String res = caller.getClassName() + ":" + caller.getMethodName() + "(): \n" + msg;
        return new String[] { msgTag, res };
    }
}

use file() method muse have permission of "android.permission.WRITE_EXTERNAL_STORAGE"