1 /** 2 * Copyright (c) 2004-2011 QOS.ch 3 * All rights reserved. 4 * 5 * Permission is hereby granted, free of charge, to any person obtaining 6 * a copy of this software and associated documentation files (the 7 * "Software"), to deal in the Software without restriction, including 8 * without limitation the rights to use, copy, modify, merge, publish, 9 * distribute, sublicense, and/or sell copies of the Software, and to 10 * permit persons to whom the Software is furnished to do so, subject to 11 * the following conditions: 12 * 13 * The above copyright notice and this permission notice shall be 14 * included in all copies or substantial portions of the Software. 15 * 16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 17 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 18 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 19 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE 20 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION 21 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION 22 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 23 * 24 */ 25 package org.slf4j; 26 27 import org.slf4j.MDC; 28 29 public class NDC { 30 public final static String PREFIX = "NDC"; 31 32 private static int size() { 33 int i = 0; 34 while (true) { 35 String val = MDC.get(PREFIX + i); 36 if (val != null) { 37 i++; 38 } else { 39 break; 40 } 41 } 42 return i; 43 } 44 45 public static void push(String val) { 46 int next = size(); 47 MDC.put(PREFIX + next, val); 48 } 49 50 public static String pop() { 51 int next = size(); 52 if (next == 0) { 53 return ""; 54 } 55 int last = next - 1; 56 String key = PREFIX + last; 57 String val = MDC.get(key); 58 MDC.remove(key); 59 return val; 60 } 61 62 } 63
