Get the Class name and Method Name at any Location in Java /Android

Question

I am android developer and love logging very much. I had been using a convention for my logs that is in form of

[ClassName:methodName()]

Whenever i have to log something, this help me find exact location from where a specific log is generated and helpful in many cases.

Instead of writing each time the

ClassName

and

MethodName

manually i wrote a method. Their may be better approach of doing this. Any answer without using loop is Accepted.

public static String getRef(Object object) {
        StackTraceElement[] elements = Thread.currentThread().getStackTrace();
        String method = "";
        if (elements.length > 0) {
            for (int i = 0; i < elements.length; i++) {
                if (elements[i].getClassName().equals(object.getClass().getCanonicalName())) {
                    method = elements[i].getMethodName();
                    break;
                }
            }
        }
        return "[" + object.getClass().getSimpleName() + "::" + method + "()]";
    }

Calling:

Log.d(STRING_TAG , GlobalConfig.getRef(this) + " Server Response:"+json);

i had already tried using

Object.getClass().getEnclosingMethod();

but its always returning me null and also it is supposed to return the method name where it is called right? as the documentation says

If this Class object represents a local or anonymous class within a method, returns a Method object representing the immediately enclosing method of the underlying class. Returns null otherwise. In particular, this method returns null if the underlying class is a local or anonymous class immediately enclosed by a type declaration, instance initializer or static initializer.
Return
Method the immediately enclosing method of the underlying class, if that class is a local or anonymous class; otherwise null.

Use slf4j and log4j there you can simply configure the outpus as you like, no need to reinvent the wheel... — Timothy Truckle
– Timothy Truckle, Commented May 18, 2017 at 7:42
@TimothyTruckle thanks for your feedback, actually android does have its own Logging Library, all i want is to get the method name at any point in application. — Azmat Karim Khan
– Azmat Karim Khan, Commented May 18, 2017 at 7:46
" android does have its own Logging Library" - wrong: slf4j.org/android — Timothy Truckle
– Timothy Truckle, Commented May 18, 2017 at 8:48

Bruno · Accepted Answer · 2017-05-18 15:31:52Z

2

If you going to call it directly, I explain:

You are on class A, and want to log that you are here
You will call this method directly from class A

You can use this:

 StackTraceElement[] elements = Thread.currentThread().getStackTrace();
 String method = "";
 method = elements[elements.length - 2].getMethodName();
 return "[" + object.getClass().getSimpleName() + "::" + method + "()]";

Where you get the last but one class called. Ex:

public class Random {

 public static void main(String[] args) {
  Random r = new Random();
  r.test();
 }

 public void test() {
  System.out.println(Logger.getRef(this));
 }

}

class Logger {

 public static String getRef(Object object) {
  StackTraceElement[] elements = Thread.currentThread().getStackTrace();
  String method = "";
  method = elements[2].getMethodName();
  return "[" + object.getClass().getSimpleName() + "::" + method + "()]";
 }

}

Out: [Random::test()]

edited May 18, 2017 at 15:31

answered May 18, 2017 at 11:00

Bruno

3,1191 gold badge21 silver badges25 bronze badges

Sign up to request clarification or add additional context in comments.

9 Comments

Azmat Karim Khan Over a year ago

you cannot find the index statically elements[elements.length - 2]

Bruno Over a year ago

Sorry, but, why not? I mean, if you want the caller, it will be that last but one in the array. Even when you call Log.d(STRING_TAG , GlobalConfig.getRef(this) + " Server Response:"+json);. That is the only way to get the information you want without looping through all the index and checking by class name

Azmat Karim Khan Over a year ago

what if there are other elements in StackTrace, according to your code that is right

Azmat Karim Khan Over a year ago

public static Random r; public static void main(String[] args) { r = new Random(); new Thread(new Runnable(){ public void run(){ r.test(); for(int i=0;i<100;i=i+2){ //do something System.out.println("working:"); } } }).start(); }

Azmat Karim Khan Over a year ago

Make the above change and then try, you cannot fix the element and its not always the second last one

|

Collectives™ on Stack Overflow

Get the Class name and Method Name at any Location in Java /Android

1 Answer 1

9 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

9 Comments

Your Answer

Sign up or log in

Post as a guest

Related