1 package org.apache.log4j;
2
3 import java.lang.reflect.Field;
4 import java.lang.reflect.Method;
5
6 import org.apache.log4j.helpers.ThreadLocalMap;
7
8 public class MDCFriend {
9
10 public static void fixForJava9() {
11 try {
12 Field mdcField = MDC.class.getDeclaredField("mdc");
13
14 MDC mdcSingleton = (MDC) mdcField.get(null);
15 Field tlmField = MDC.class.getDeclaredField("tlm");
16
17 Field java1Field = MDC.class.getDeclaredField("java1");
18 Object mdcSingleton_tlm = tlmField.get(mdcSingleton);
19
20 if (mdcSingleton_tlm == null) {
21 tlmField.set(mdcSingleton, new ThreadLocalMap());
22 java1Field.setBoolean(mdcSingleton, false);
23 setRemoveMethod(mdcSingleton);
24 }
25 } catch (SecurityException e) {
26 e.printStackTrace();
27 } catch (NoSuchFieldException e) {
28 e.printStackTrace();
29 } catch (IllegalArgumentException e) {
30 e.printStackTrace();
31 } catch (IllegalAccessException e) {
32 e.printStackTrace();
33 }
34
35 }
36
37 private static void setRemoveMethod(org.apache.log4j.MDC mdc) {
38 try {
39 Method removeMethod = ThreadLocal.class.getMethod("remove");
40 Field removeMethodField = MDC.class.getDeclaredField("removeMethod");
41 removeMethodField.setAccessible(true);
42 removeMethodField.set(mdc, removeMethod);
43 } catch (NoSuchMethodException e) {
44 e.printStackTrace();
45 } catch (SecurityException e) {
46 e.printStackTrace();
47 } catch (NoSuchFieldException e) {
48 e.printStackTrace();
49 } catch (IllegalArgumentException e) {
50 e.printStackTrace();
51 } catch (IllegalAccessException e) {
52 e.printStackTrace();
53 }
54
55 }
56 }