Custom Log Util

MyLog.java

package cn.septenary;


import java.util.Locale;

public class MyLog {
    // adb shell setprop log.tag.MyLog VERBOSE
    
    public static String TAG = "MyLog";
    
    public static boolean DEBUG;

    static {
        DEBUG = android.util.Log.isLoggable("MyLog", android.util.Log.VERBOSE);
    }

    public MyLog() {

    }

    public static void setTag(String tag) {
        d("Changing log tag to %s", new Object[]{tag});
        TAG = tag;
        DEBUG = android.util.Log.isLoggable(TAG, android.util.Log.VERBOSE);
    }

    public static void v(String format, Object... args) {
        if (DEBUG) {
            android.util.Log.v(TAG, buildMessage(format, args));
        }
    }

    public static void d(String format, Object... args) {
        if (DEBUG) {
            android.util.Log.d(TAG, buildMessage(format, args));
        }
    }

    public static void e(String format, Object... args) {
        if (DEBUG) {
            android.util.Log.e(TAG, buildMessage(format, args));
        }
    }

    public static void e(Throwable tr, String format, Object... args) {
        if (DEBUG) {
            android.util.Log.e(TAG, buildMessage(format, args), tr);
        }
    }

    public static void wtf(String format, Object... args) {
        if (DEBUG) {
            android.util.Log.wtf(TAG, buildMessage(format, args));
        }
    }

    public static void wtf(Throwable tr, String format, Object... args) {
        if (DEBUG) {
            android.util.Log.wtf(TAG, buildMessage(format, args), tr);
        }
    }

    private static String buildMessage(String format, Object... args) {
        String msg = args == null ? format : String.format(Locale.US, format, args);
        StackTraceElement[] trace = (new Throwable()).fillInStackTrace().getStackTrace();
        String caller = "<unknown>";

        for (int i = 2; i < trace.length; ++i) {
            Class clazz = trace[i].getClass();
            if (!clazz.equals(MyLog.class)) {
                String callingClass = trace[i].getClassName();
                callingClass = callingClass.substring(callingClass.lastIndexOf(46) + 1);
                callingClass = callingClass.substring(callingClass.lastIndexOf(36) + 1);
                caller = callingClass + "." + trace[i].getMethodName();
                break;
            }
        }

        return String.format(Locale.US, "[%d] %s: %s", new Object[]{Long.valueOf(Thread.currentThread().getId()), caller, msg});
    }

}