1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17 package org.apache.logging.log4j.core.lookup;
18
19 import java.util.HashMap;
20 import java.util.List;
21 import java.util.Locale;
22 import java.util.Map;
23
24 import org.apache.logging.log4j.Logger;
25 import org.apache.logging.log4j.core.LogEvent;
26 import org.apache.logging.log4j.core.config.ConfigurationAware;
27 import org.apache.logging.log4j.core.config.plugins.util.PluginManager;
28 import org.apache.logging.log4j.core.config.plugins.util.PluginType;
29 import org.apache.logging.log4j.core.util.Loader;
30 import org.apache.logging.log4j.core.util.ReflectionUtil;
31 import org.apache.logging.log4j.status.StatusLogger;
32
33
34
35
36 public class Interpolator extends AbstractConfigurationAwareLookup {
37
38 private static final String LOOKUP_KEY_WEB = "web";
39
40 private static final String LOOKUP_KEY_JNDI = "jndi";
41
42 private static final String LOOKUP_KEY_JVMRUNARGS = "jvmrunargs";
43
44 private static final Logger LOGGER = StatusLogger.getLogger();
45
46
47 private static final char PREFIX_SEPARATOR = ':';
48
49 private final Map<String, StrLookup> lookups = new HashMap<>();
50
51 private final StrLookup defaultLookup;
52
53 public Interpolator(final StrLookup defaultLookup) {
54 this(defaultLookup, null);
55 }
56
57
58
59
60
61
62
63
64 public Interpolator(final StrLookup defaultLookup, final List<String> pluginPackages) {
65 this.defaultLookup = defaultLookup == null ? new MapLookup(new HashMap<String, String>()) : defaultLookup;
66 final PluginManager manager = new PluginManager(CATEGORY);
67 manager.collectPlugins(pluginPackages);
68 final Map<String, PluginType<?>> plugins = manager.getPlugins();
69
70 for (final Map.Entry<String, PluginType<?>> entry : plugins.entrySet()) {
71 try {
72 final Class<? extends StrLookup> clazz = entry.getValue().getPluginClass().asSubclass(StrLookup.class);
73 lookups.put(entry.getKey(), ReflectionUtil.instantiate(clazz));
74 } catch (final Throwable t) {
75 handleError(entry.getKey(), t);
76 }
77 }
78 }
79
80
81
82
83 public Interpolator() {
84 this((Map<String, String>) null);
85 }
86
87
88
89
90 public Interpolator(final Map<String, String> properties) {
91 this.defaultLookup = new MapLookup(properties == null ? new HashMap<String, String>() : properties);
92
93 lookups.put("log4j", new Log4jLookup());
94 lookups.put("sys", new SystemPropertiesLookup());
95 lookups.put("env", new EnvironmentLookup());
96 lookups.put("main", MainMapLookup.MAIN_SINGLETON);
97 lookups.put("marker", new MarkerLookup());
98 lookups.put("java", new JavaLookup());
99
100 try {
101
102 lookups.put(LOOKUP_KEY_JNDI,
103 Loader.newCheckedInstanceOf("org.apache.logging.log4j.core.lookup.JndiLookup", StrLookup.class));
104 } catch (final LinkageError | Exception e) {
105 handleError(LOOKUP_KEY_JNDI, e);
106 }
107
108 try {
109
110 lookups.put(LOOKUP_KEY_JVMRUNARGS,
111 Loader.newCheckedInstanceOf("org.apache.logging.log4j.core.lookup.JmxRuntimeInputArgumentsLookup",
112 StrLookup.class));
113 } catch (final LinkageError | Exception e) {
114 handleError(LOOKUP_KEY_JVMRUNARGS, e);
115 }
116 lookups.put("date", new DateLookup());
117 lookups.put("ctx", new ContextMapLookup());
118 if (Loader.isClassAvailable("javax.servlet.ServletContext")) {
119 try {
120 lookups.put(LOOKUP_KEY_WEB,
121 Loader.newCheckedInstanceOf("org.apache.logging.log4j.web.WebLookup", StrLookup.class));
122 } catch (final Exception ignored) {
123 handleError(LOOKUP_KEY_WEB, ignored);
124 }
125 } else {
126 LOGGER.debug("Not in a ServletContext environment, thus not loading WebLookup plugin.");
127 }
128 }
129
130 private void handleError(final String lookupKey, final Throwable t) {
131 switch (lookupKey) {
132 case LOOKUP_KEY_JNDI:
133
134 LOGGER.warn(
135 "JNDI lookup class is not available because this JRE does not support JNDI." +
136 " JNDI string lookups will not be available, continuing configuration. Ignoring " + t);
137 break;
138 case LOOKUP_KEY_JVMRUNARGS:
139
140 LOGGER.warn(
141 "JMX runtime input lookup class is not available because this JRE does not support JMX. " +
142 "JMX lookups will not be available, continuing configuration. Ignoring " + t);
143 break;
144 case LOOKUP_KEY_WEB:
145 LOGGER.info("Log4j appears to be running in a Servlet environment, but there's no log4j-web module " +
146 "available. If you want better web container support, please add the log4j-web JAR to your " +
147 "web archive or server lib directory.");
148 break;
149 default:
150 LOGGER.error("Unable to create Lookup for {}", lookupKey, t);
151 }
152 }
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167 @Override
168 public String lookup(final LogEvent event, String var) {
169 if (var == null) {
170 return null;
171 }
172
173 final int prefixPos = var.indexOf(PREFIX_SEPARATOR);
174 if (prefixPos >= 0) {
175 final String prefix = var.substring(0, prefixPos).toLowerCase(Locale.US);
176 final String name = var.substring(prefixPos + 1);
177 final StrLookup lookup = lookups.get(prefix);
178 if (lookup instanceof ConfigurationAware) {
179 ((ConfigurationAware) lookup).setConfiguration(configuration);
180 }
181 String value = null;
182 if (lookup != null) {
183 value = event == null ? lookup.lookup(name) : lookup.lookup(event, name);
184 }
185
186 if (value != null) {
187 return value;
188 }
189 var = var.substring(prefixPos + 1);
190 }
191 if (defaultLookup != null) {
192 return event == null ? defaultLookup.lookup(var) : defaultLookup.lookup(event, var);
193 }
194 return null;
195 }
196
197 @Override
198 public String toString() {
199 final StringBuilder sb = new StringBuilder();
200 for (final String name : lookups.keySet()) {
201 if (sb.length() == 0) {
202 sb.append('{');
203 } else {
204 sb.append(", ");
205 }
206
207 sb.append(name);
208 }
209 if (sb.length() > 0) {
210 sb.append('}');
211 }
212 return sb.toString();
213 }
214 }