text: /* Copyright (c) 2010-2012,
   *  Jinseong Jeon <jsjeon@cs.umd.edu>
   *  Kris Micinski <micinski@cs.umd.edu>
   *  Jeff Foster   <jfoster@cs.umd.edu>
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions are met:
   *
   * 1. Redistributions of source code must retain the above copyright notice,
   * this list of conditions and the following disclaimer.
   *
   * 2. Redistributions in binary form must reproduce the above copyright notice,
   * this list of conditions and the following disclaimer in the documentation
   * and/or other materials provided with the distribution.
   *
   * 3. The names of the contributors may not be used to endorse or promote
   * products derived from this software without specific prior written
   * permission.
  
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
   * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
   * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
   * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
   * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
   * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
   * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
   * POSSIBILITY OF SUCH DAMAGE.
   */
  
  /*
   * CallTracer using Java StackTraceElement
   */
  
  package org.umd.logging.util;
  
  import java.lang.Throwable;
  import java.lang.StackTraceElement;
  
  public class CallTracer {
    private static boolean partly_equal(String s1, String s2) {
      if (s1.length() < 4) return false;
      int pos1 = s1.lastIndexOf('.');
      int pos2 = s2.lastIndexOf('.');
      String ss1 = s1.substring(0, pos1);
      String ss2 = s2.substring(0, pos2);
      if (ss1.equals(ss2)) return true;
      return partly_equal(ss1, ss2);
    }
  
    public static String getChildClass() {
      String caller = "";
      StackTraceElement elts[] = (new Throwable ()).getStackTrace();
      // 0 : org.umd.logging.util.CallTracer
      // 1 : org.umd.logging.util.Logger
      // from the caller, trace back the stack
      for (int i = 2; i < elts.length; i++) {
        String name = elts[i].getClassName();
        // until we met the app's component, not ours nor systems
        if (!name.contains("umd.logging") && !name.startsWith("java")
         && !name.startsWith("android") && !name.startsWith("dalvik")) {
          // instead of returning comp's name immediately,
          // keep searching to deal with app's own hierarchy
          if (caller == "" || partly_equal(caller, name)) {
            caller = name;
          }
        }
      }
      if (caller != "") return caller;
      return "something wrong: assumed this method would be called by Logger";
    }
  }
  