| Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||
| CallContext |
|
| 1.5;1.5 |
| 1 | /** | |
| 2 | * Distribution License: | |
| 3 | * JSword is free software; you can redistribute it and/or modify it under | |
| 4 | * the terms of the GNU Lesser General Public License, version 2.1 or later | |
| 5 | * as published by the Free Software Foundation. This program is distributed | |
| 6 | * in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even | |
| 7 | * the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. | |
| 8 | * See the GNU Lesser General Public License for more details. | |
| 9 | * | |
| 10 | * The License is available on the internet at: | |
| 11 | * http://www.gnu.org/copyleft/lgpl.html | |
| 12 | * or by writing to: | |
| 13 | * Free Software Foundation, Inc. | |
| 14 | * 59 Temple Place - Suite 330 | |
| 15 | * Boston, MA 02111-1307, USA | |
| 16 | * | |
| 17 | * © CrossWire Bible Society, 2005 - 2016 | |
| 18 | * | |
| 19 | */ | |
| 20 | package org.crosswire.common.util; | |
| 21 | ||
| 22 | ||
| 23 | /** | |
| 24 | * This singleton class provides a way for a method to determine which class | |
| 25 | * called it. | |
| 26 | * <p> | |
| 27 | * It has been tested to work in command line and WebStart environments. | |
| 28 | * | |
| 29 | * @see gnu.lgpl.License The GNU Lesser General Public License for details. | |
| 30 | * @author DM Smith | |
| 31 | */ | |
| 32 | public final class CallContext { | |
| 33 | /** | |
| 34 | * Prevent instantiation | |
| 35 | */ | |
| 36 | 0 | private CallContext() { |
| 37 | 0 | } |
| 38 | ||
| 39 | /** | |
| 40 | * Singleton accessor | |
| 41 | * | |
| 42 | * @return this singleton | |
| 43 | */ | |
| 44 | public static CallContext instance() { | |
| 45 | 0 | return resolver; |
| 46 | } | |
| 47 | ||
| 48 | /** | |
| 49 | * When called from a method it will return the class calling that method. | |
| 50 | * | |
| 51 | * @return the immediate calling class | |
| 52 | */ | |
| 53 | public static Class<?> getCallingClass() { | |
| 54 | 0 | return getCallingClass(1); // add 1 for this method |
| 55 | } | |
| 56 | ||
| 57 | /** | |
| 58 | * When called from a method it will return the i-th class calling that | |
| 59 | * method, up the call chain. If used with a -1 it will return the class | |
| 60 | * making the call -2 and -3 will return this class | |
| 61 | * | |
| 62 | * @param i the i-th coller | |
| 63 | * @return the desired calling class | |
| 64 | * @throws ArrayIndexOutOfBoundsException | |
| 65 | * if the index is not valid | |
| 66 | */ | |
| 67 | public static Class<?> getCallingClass(int i) { | |
| 68 | try { | |
| 69 | 0 | return Class.forName(Thread.currentThread().getStackTrace()[CALL_CONTEXT_OFFSET + i].getClassName()); |
| 70 | 0 | } catch (ClassNotFoundException e) { |
| 71 | 0 | return CallContext.class; |
| 72 | } | |
| 73 | } | |
| 74 | ||
| 75 | // may need to change if this class is redesigned | |
| 76 | /** | |
| 77 | * Offset needed to represent the caller of the method that called this | |
| 78 | * method. | |
| 79 | * | |
| 80 | */ | |
| 81 | private static final int CALL_CONTEXT_OFFSET = 3; | |
| 82 | ||
| 83 | 0 | private static CallContext resolver = new CallContext(); |
| 84 | } |