13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25 package java.lang;
26
27 import java.io.*;
28 import java.lang.reflect.Executable;
29 import java.lang.annotation.Annotation;
30 import java.security.AccessControlContext;
31 import java.util.Properties;
32 import java.util.PropertyPermission;
33 import java.util.StringTokenizer;
34 import java.util.Map;
35 import java.security.AccessController;
36 import java.security.PrivilegedAction;
37 import java.security.AllPermission;
38 import java.nio.channels.Channel;
39 import java.nio.channels.spi.SelectorProvider;
40 import sun.nio.ch.Interruptible;
41 import sun.reflect.CallerSensitive;
42 import sun.reflect.Reflection;
43 import sun.security.util.SecurityConstants;
44 import sun.reflect.annotation.AnnotationType;
45 import jdk.internal.HotSpotIntrinsicCandidate;
46 import jdk.internal.misc.JavaLangAccess;;
47 import jdk.internal.misc.SharedSecrets;;
48
49 /**
50 * The <code>System</code> class contains several useful class fields
51 * and methods. It cannot be instantiated.
52 *
53 * <p>Among the facilities provided by the <code>System</code> class
54 * are standard input, standard output, and error output streams;
55 * access to externally defined properties and environment
56 * variables; a means of loading files and libraries; and a utility
57 * method for quickly copying a portion of an array.
58 *
59 * @author unascribed
60 * @since 1.0
61 */
62 public final class System {
63
64 /* register the natives via the static initializer.
65 *
66 * VM will invoke the initializeSystemClass method to complete
67 * the initialization for this class separated from clinit.
927 *
928 * @return the environment as a map of variable names to values
929 * @throws SecurityException
930 * if a security manager exists and its
931 * {@link SecurityManager#checkPermission checkPermission}
932 * method doesn't allow access to the process environment
933 * @see #getenv(String)
934 * @see ProcessBuilder#environment()
935 * @since 1.5
936 */
937 public static java.util.Map<String,String> getenv() {
938 SecurityManager sm = getSecurityManager();
939 if (sm != null) {
940 sm.checkPermission(new RuntimePermission("getenv.*"));
941 }
942
943 return ProcessEnvironment.getenv();
944 }
945
946 /**
947 * Terminates the currently running Java Virtual Machine. The
948 * argument serves as a status code; by convention, a nonzero status
949 * code indicates abnormal termination.
950 * <p>
951 * This method calls the <code>exit</code> method in class
952 * <code>Runtime</code>. This method never returns normally.
953 * <p>
954 * The call <code>System.exit(n)</code> is effectively equivalent to
955 * the call:
956 * <blockquote><pre>
957 * Runtime.getRuntime().exit(n)
958 * </pre></blockquote>
959 *
960 * @param status exit status.
961 * @throws SecurityException
962 * if a security manager exists and its <code>checkExit</code>
963 * method doesn't allow exit with the specified status.
964 * @see java.lang.Runtime#exit(int)
965 */
966 public static void exit(int status) {
|
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25 package java.lang;
26
27 import java.io.*;
28 import java.lang.reflect.Executable;
29 import java.lang.annotation.Annotation;
30 import java.security.AccessControlContext;
31 import java.util.Properties;
32 import java.util.PropertyPermission;
33 import java.util.Map;
34 import java.security.AccessController;
35 import java.security.PrivilegedAction;
36 import java.nio.channels.Channel;
37 import java.nio.channels.spi.SelectorProvider;
38 import java.util.Objects;
39 import java.util.ResourceBundle;
40 import java.util.function.Supplier;
41 import sun.nio.ch.Interruptible;
42 import sun.reflect.CallerSensitive;
43 import sun.reflect.Reflection;
44 import sun.security.util.SecurityConstants;
45 import sun.reflect.annotation.AnnotationType;
46 import jdk.internal.HotSpotIntrinsicCandidate;
47 import jdk.internal.misc.JavaLangAccess;;
48 import jdk.internal.misc.SharedSecrets;;
49 import jdk.internal.logger.LoggerFinderLoader;
50 import jdk.internal.logger.LazyLoggers;
51 import jdk.internal.logger.LocalizedLoggerWrapper;
52
53 /**
54 * The <code>System</code> class contains several useful class fields
55 * and methods. It cannot be instantiated.
56 *
57 * <p>Among the facilities provided by the <code>System</code> class
58 * are standard input, standard output, and error output streams;
59 * access to externally defined properties and environment
60 * variables; a means of loading files and libraries; and a utility
61 * method for quickly copying a portion of an array.
62 *
63 * @author unascribed
64 * @since 1.0
65 */
66 public final class System {
67
68 /* register the natives via the static initializer.
69 *
70 * VM will invoke the initializeSystemClass method to complete
71 * the initialization for this class separated from clinit.
931 *
932 * @return the environment as a map of variable names to values
933 * @throws SecurityException
934 * if a security manager exists and its
935 * {@link SecurityManager#checkPermission checkPermission}
936 * method doesn't allow access to the process environment
937 * @see #getenv(String)
938 * @see ProcessBuilder#environment()
939 * @since 1.5
940 */
941 public static java.util.Map<String,String> getenv() {
942 SecurityManager sm = getSecurityManager();
943 if (sm != null) {
944 sm.checkPermission(new RuntimePermission("getenv.*"));
945 }
946
947 return ProcessEnvironment.getenv();
948 }
949
950 /**
951 * {@code System.Logger} instances log messages that will be
952 * routed to the underlying logging framework the {@link System.LoggerFinder
953 * LoggerFinder} uses.
954 * <p>
955 * {@code System.Logger} instances are typically obtained from
956 * the {@link java.lang.System System} class, by calling
957 * {@link java.lang.System#getLogger(java.lang.String) System.getLogger(loggerName)}
958 * or {@link java.lang.System#getLogger(java.lang.String, java.util.ResourceBundle)
959 * System.getLogger(loggerName, bundle)}.
960 *
961 * @see java.lang.System#getLogger(java.lang.String)
962 * @see java.lang.System#getLogger(java.lang.String, java.util.ResourceBundle)
963 * @see java.lang.System.LoggerFinder
964 *
965 * @since 9
966 *
967 */
968 public interface Logger {
969
970 /**
971 * System {@linkplain Logger loggers} levels.
972 * <p>
973 * A level has a {@linkplain #getName() name} and {@linkplain
974 * #getSeverity() severity}.
975 * Level values are {@link #ALL}, {@link #TRACE}, {@link #DEBUG},
976 * {@link #INFO}, {@link #WARNING}, {@link #ERROR}, {@link #OFF},
977 * by order of increasing severity.
978 * <br>
979 * {@link #ALL} and {@link #OFF}
980 * are simple markers with severities mapped respectively to
981 * {@link java.lang.Integer#MIN_VALUE Integer.MIN_VALUE} and
982 * {@link java.lang.Integer#MAX_VALUE Integer.MAX_VALUE}.
983 * <p>
984 * <b>Severity values and Mapping to {@code java.util.logging.Level}.</b>
985 * <p>
986 * {@linkplain System.Logger.Level System logger levels} are mapped to
987 * {@linkplain java.util.logging.Level java.util.logging levels}
988 * of corresponding severity.
989 * <br>The mapping is as follows:
990 * <br><br>
991 * <table border="1">
992 * <caption>System.Logger Severity Level Mapping</caption>
993 * <tr><td><b>System.Logger Levels</b></td>
994 * <td>{@link Logger.Level#ALL ALL}</td>
995 * <td>{@link Logger.Level#TRACE TRACE}</td>
996 * <td>{@link Logger.Level#DEBUG DEBUG}</td>
997 * <td>{@link Logger.Level#INFO INFO}</td>
998 * <td>{@link Logger.Level#WARNING WARNING}</td>
999 * <td>{@link Logger.Level#ERROR ERROR}</td>
1000 * <td>{@link Logger.Level#OFF OFF}</td>
1001 * </tr>
1002 * <tr><td><b>java.util.logging Levels</b></td>
1003 * <td>{@link java.util.logging.Level#ALL ALL}</td>
1004 * <td>{@link java.util.logging.Level#FINER FINER}</td>
1005 * <td>{@link java.util.logging.Level#FINE FINE}</td>
1006 * <td>{@link java.util.logging.Level#INFO INFO}</td>
1007 * <td>{@link java.util.logging.Level#WARNING WARNING}</td>
1008 * <td>{@link java.util.logging.Level#SEVERE SEVERE}</td>
1009 * <td>{@link java.util.logging.Level#OFF OFF}</td>
1010 * </tr>
1011 * </table>
1012 *
1013 * @since 9
1014 *
1015 * @see java.lang.System.LoggerFinder
1016 * @see java.lang.System.Logger
1017 */
1018 public enum Level {
1019
1020 // for convenience, we're reusing java.util.logging.Level int values
1021 // the mapping logic in sun.util.logging.PlatformLogger depends
1022 // on this.
1023 /**
1024 * A marker to indicate that all levels are enabled.
1025 * This level {@linkplain #getSeverity() severity} is
1026 * {@link Integer#MIN_VALUE}.
1027 */
1028 ALL(Integer.MIN_VALUE), // typically mapped to/from j.u.l.Level.ALL
1029 /**
1030 * {@code TRACE} level: usually used to log diagnostic information.
1031 * This level {@linkplain #getSeverity() severity} is
1032 * {@code 400}.
1033 */
1034 TRACE(400), // typically mapped to/from j.u.l.Level.FINER
1035 /**
1036 * {@code DEBUG} level: usually used to log debug information traces.
1037 * This level {@linkplain #getSeverity() severity} is
1038 * {@code 500}.
1039 */
1040 DEBUG(500), // typically mapped to/from j.u.l.Level.FINEST/FINE/CONFIG
1041 /**
1042 * {@code INFO} level: usually used to log information messages.
1043 * This level {@linkplain #getSeverity() severity} is
1044 * {@code 800}.
1045 */
1046 INFO(800), // typically mapped to/from j.u.l.Level.INFO
1047 /**
1048 * {@code WARNING} level: usually used to log warning messages.
1049 * This level {@linkplain #getSeverity() severity} is
1050 * {@code 900}.
1051 */
1052 WARNING(900), // typically mapped to/from j.u.l.Level.WARNING
1053 /**
1054 * {@code ERROR} level: usually used to log error messages.
1055 * This level {@linkplain #getSeverity() severity} is
1056 * {@code 1000}.
1057 */
1058 ERROR(1000), // typically mapped to/from j.u.l.Level.SEVERE
1059 /**
1060 * A marker to indicate that all levels are disabled.
1061 * This level {@linkplain #getSeverity() severity} is
1062 * {@link Integer#MAX_VALUE}.
1063 */
1064 OFF(Integer.MAX_VALUE); // typically mapped to/from j.u.l.Level.OFF
1065
1066 private final int severity;
1067
1068 private Level(int severity) {
1069 this.severity = severity;
1070 }
1071
1072 /**
1073 * Returns the name of this level.
1074 * @return this level {@linkplain #name()}.
1075 */
1076 public final String getName() {
1077 return name();
1078 }
1079
1080 /**
1081 * Returns the severity of this level.
1082 * A higher severity means a more severe condition.
1083 * @return this level severity.
1084 */
1085 public final int getSeverity() {
1086 return severity;
1087 }
1088 }
1089
1090 /**
1091 * Returns the name of this logger.
1092 *
1093 * @return the logger name.
1094 */
1095 public String getName();
1096
1097 /**
1098 * Checks if a message of the given level would be logged by
1099 * this logger.
1100 *
1101 * @param level the log message level.
1102 * @return {@code true} if the given log message level is currently
1103 * being logged.
1104 *
1105 * @throws NullPointerException if {@code level} is {@code null}.
1106 */
1107 public boolean isLoggable(Level level);
1108
1109 /**
1110 * Logs a message.
1111 *
1112 * @implSpec The default implementation for this method calls
1113 * {@code this.log(level, (ResourceBundle)null, msg, (Object[])null);}
1114 *
1115 * @param level the log message level.
1116 * @param msg the string message (or a key in the message catalog, if
1117 * this logger is a {@link
1118 * LoggerFinder#getLocalizedLogger(java.lang.String, java.util.ResourceBundle, java.lang.Class)
1119 * localized logger}); can be {@code null}.
1120 *
1121 * @throws NullPointerException if {@code level} is {@code null}.
1122 */
1123 public default void log(Level level, String msg) {
1124 log(level, (ResourceBundle) null, msg, (Object[]) null);
1125 }
1126
1127 /**
1128 * Logs a lazily supplied message.
1129 * <p>
1130 * If the logger is currently enabled for the given log message level
1131 * then a message is logged that is the result produced by the
1132 * given supplier function. Otherwise, the supplier is not operated on.
1133 *
1134 * @implSpec When logging is enabled for the given level, the default
1135 * implementation for this method calls
1136 * {@code this.log(level, (ResourceBundle)null, msgSupplier.get(), (Object[])null);}
1137 *
1138 * @param level the log message level.
1139 * @param msgSupplier a supplier function that produces a message.
1140 *
1141 * @throws NullPointerException if {@code level} is {@code null},
1142 * or {@code msgSupplier} is {@code null}.
1143 */
1144 public default void log(Level level, Supplier<String> msgSupplier) {
1145 Objects.requireNonNull(msgSupplier);
1146 if (isLoggable(Objects.requireNonNull(level))) {
1147 log(level, (ResourceBundle) null, msgSupplier.get(), (Object[]) null);
1148 }
1149 }
1150
1151 /**
1152 * Logs a message produced from the given object.
1153 * <p>
1154 * If the logger is currently enabled for the given log message level then
1155 * a message is logged that, by default, is the result produced from
1156 * calling toString on the given object.
1157 * Otherwise, the object is not operated on.
1158 *
1159 * @implSpec When logging is enabled for the given level, the default
1160 * implementation for this method calls
1161 * {@code this.log(level, (ResourceBundle)null, obj.toString(), (Object[])null);}
1162 *
1163 * @param level the log message level.
1164 * @param obj the object to log.
1165 *
1166 * @throws NullPointerException if {@code level} is {@code null}, or
1167 * {@code obj} is {@code null}.
1168 */
1169 public default void log(Level level, Object obj) {
1170 Objects.requireNonNull(obj);
1171 if (isLoggable(Objects.requireNonNull(level))) {
1172 this.log(level, (ResourceBundle) null, obj.toString(), (Object[]) null);
1173 }
1174 }
1175
1176 /**
1177 * Logs a message associated with a given throwable.
1178 *
1179 * @implSpec The default implementation for this method calls
1180 * {@code this.log(level, (ResourceBundle)null, msg, thrown);}
1181 *
1182 * @param level the log message level.
1183 * @param msg the string message (or a key in the message catalog, if
1184 * this logger is a {@link
1185 * LoggerFinder#getLocalizedLogger(java.lang.String, java.util.ResourceBundle, java.lang.Class)
1186 * localized logger}); can be {@code null}.
1187 * @param thrown a {@code Throwable} associated with the log message;
1188 * can be {@code null}.
1189 *
1190 * @throws NullPointerException if {@code level} is {@code null}.
1191 */
1192 public default void log(Level level, String msg, Throwable thrown) {
1193 this.log(level, null, msg, thrown);
1194 }
1195
1196 /**
1197 * Logs a lazily supplied message associated with a given throwable.
1198 * <p>
1199 * If the logger is currently enabled for the given log message level
1200 * then a message is logged that is the result produced by the
1201 * given supplier function. Otherwise, the supplier is not operated on.
1202 *
1203 * @implSpec When logging is enabled for the given level, the default
1204 * implementation for this method calls
1205 * {@code this.log(level, (ResourceBundle)null, msgSupplier.get(), thrown);}
1206 *
1207 * @param level one of the log message level identifiers.
1208 * @param msgSupplier a supplier function that produces a message.
1209 * @param thrown a {@code Throwable} associated with log message;
1210 * can be {@code null}.
1211 *
1212 * @throws NullPointerException if {@code level} is {@code null}, or
1213 * {@code msgSupplier} is {@code null}.
1214 */
1215 public default void log(Level level, Supplier<String> msgSupplier,
1216 Throwable thrown) {
1217 Objects.requireNonNull(msgSupplier);
1218 if (isLoggable(Objects.requireNonNull(level))) {
1219 this.log(level, null, msgSupplier.get(), thrown);
1220 }
1221 }
1222
1223 /**
1224 * Logs a message with an optional list of parameters.
1225 *
1226 * @implSpec The default implementation for this method calls
1227 * {@code this.log(level, (ResourceBundle)null, format, params);}
1228 *
1229 * @param level one of the log message level identifiers.
1230 * @param format the string message format in {@link
1231 * java.text.MessageFormat} format, (or a key in the message
1232 * catalog, if this logger is a {@link
1233 * LoggerFinder#getLocalizedLogger(java.lang.String, java.util.ResourceBundle, java.lang.Class)
1234 * localized logger}); can be {@code null}.
1235 * @param params an optional list of parameters to the message (may be
1236 * none).
1237 *
1238 * @throws NullPointerException if {@code level} is {@code null}.
1239 */
1240 public default void log(Level level, String format, Object... params) {
1241 this.log(level, null, format, params);
1242 }
1243
1244 /**
1245 * Logs a localized message associated with a given throwable.
1246 * <p>
1247 * If the given resource bundle is non-{@code null}, the {@code msg}
1248 * string is localized using the given resource bundle.
1249 * Otherwise the {@code msg} string is not localized.
1250 *
1251 * @param level the log message level.
1252 * @param bundle a resource bundle to localize {@code msg}; can be
1253 * {@code null}.
1254 * @param msg the string message (or a key in the message catalog,
1255 * if {@code bundle} is not {@code null}); can be {@code null}.
1256 * @param thrown a {@code Throwable} associated with the log message;
1257 * can be {@code null}.
1258 *
1259 * @throws NullPointerException if {@code level} is {@code null}.
1260 */
1261 public void log(Level level, ResourceBundle bundle, String msg,
1262 Throwable thrown);
1263
1264 /**
1265 * Logs a message with resource bundle and an optional list of
1266 * parameters.
1267 * <p>
1268 * If the given resource bundle is non-{@code null}, the {@code format}
1269 * string is localized using the given resource bundle.
1270 * Otherwise the {@code format} string is not localized.
1271 *
1272 * @param level the log message level.
1273 * @param bundle a resource bundle to localize {@code format}; can be
1274 * {@code null}.
1275 * @param format the string message format in {@link
1276 * java.text.MessageFormat} format, (or a key in the message
1277 * catalog if {@code bundle} is not {@code null}); can be {@code null}.
1278 * @param params an optional list of parameters to the message (may be
1279 * none).
1280 *
1281 * @throws NullPointerException if {@code level} is {@code null}.
1282 */
1283 public void log(Level level, ResourceBundle bundle, String format,
1284 Object... params);
1285
1286
1287 }
1288
1289 /**
1290 * The {@code LoggerFinder} service is responsible for creating, managing,
1291 * and configuring loggers to the underlying framework it uses.
1292 * <p>
1293 * A logger finder is a concrete implementation of this class that has a
1294 * zero-argument constructor and implements the abstract methods defined
1295 * by this class.
1296 * The loggers returned from a logger finder are capable of routing log
1297 * messages to the logging backend this provider supports.
1298 * A given invocation of the Java Runtime maintains a single
1299 * system-wide LoggerFinder instance that is loaded as follows:
1300 * <ul>
1301 * <li>First it finds any custom {@code LoggerFinder} provider
1302 * using the {@link java.util.ServiceLoader} facility with the
1303 * {@linkplain ClassLoader#getSystemClassLoader() system class
1304 * loader}.</li>
1305 * <li>If no {@code LoggerFinder} provider is found, the system default
1306 * {@code LoggerFinder} implementation will be used.</li>
1307 * </ul>
1308 * <p>
1309 * An application can replace the logging backend
1310 * <i>even when the java.logging module is present</i>, by simply providing
1311 * and declaring an implementation of the {@link LoggerFinder} service.
1312 * <p>
1313 * <b>Default Implementation</b>
1314 * <p>
1315 * The system default {@code LoggerFinder} implementation uses
1316 * {@code java.util.logging} as the backend framework when the
1317 * {@code java.logging} module is present.
1318 * It returns a {@linkplain System.Logger logger} instance
1319 * that will route log messages to a {@link java.util.logging.Logger
1320 * java.util.logging.Logger}. Otherwise, if {@code java.logging} is not
1321 * present, the default implementation will return a simple logger
1322 * instance that will route log messages of {@code INFO} level and above to
1323 * the console ({@code System.err}).
1324 * <p>
1325 * <b>Logging Configuration</b>
1326 * <p>
1327 * {@linkplain Logger Logger} instances obtained from the
1328 * {@code LoggerFinder} factory methods are not directly configurable by
1329 * the application. Configuration is the responsibility of the underlying
1330 * logging backend, and usually requires using APIs specific to that backend.
1331 * <p>For the default {@code LoggerFinder} implementation
1332 * using {@code java.util.logging} as its backend, refer to
1333 * {@link java.util.logging java.util.logging} for logging configuration.
1334 * For the default {@code LoggerFinder} implementation returning simple loggers
1335 * when the {@code java.logging} module is absent, the configuration
1336 * is implementation dependent.
1337 * <p>
1338 * Usually an application that uses a logging framework will log messages
1339 * through a logger facade defined (or supported) by that framework.
1340 * Applications that wish to use an external framework should log
1341 * through the facade associated with that framework.
1342 * <p>
1343 * A system class that needs to log messages will typically obtain
1344 * a {@link System.Logger} instance to route messages to the logging
1345 * framework selected by the application.
1346 * <p>
1347 * Libraries and classes that only need loggers to produce log messages
1348 * should not attempt to configure loggers by themselves, as that
1349 * would make them dependent from a specific implementation of the
1350 * {@code LoggerFinder} service.
1351 * <p>
1352 * In addition, when a security manager is present, loggers provided to
1353 * system classes should not be directly configurable through the logging
1354 * backend without requiring permissions.
1355 * <br>
1356 * It is the responsibility of the provider of
1357 * the concrete {@code LoggerFinder} implementation to ensure that
1358 * these loggers are not configured by untrusted code without proper
1359 * permission checks, as configuration performed on such loggers usually
1360 * affects all applications in the same Java Runtime.
1361 * <p>
1362 * <b>Message Levels and Mapping to backend levels</b>
1363 * <p>
1364 * A logger finder is responsible for mapping from a {@code
1365 * System.Logger.Level} to a level supported by the logging backend it uses.
1366 * <br>The default LoggerFinder using {@code java.util.logging} as the backend
1367 * maps {@code System.Logger} levels to
1368 * {@linkplain java.util.logging.Level java.util.logging} levels
1369 * of corresponding severity - as described in {@link Logger.Level
1370 * Logger.Level}.
1371 *
1372 * @see java.lang.System
1373 * @see java.lang.System.Logger
1374 *
1375 * @since 9
1376 */
1377 public static abstract class LoggerFinder {
1378 /**
1379 * The {@code RuntimePermission("loggerFinder")} is
1380 * necessary to subclass and instantiate the {@code LoggerFinder} class,
1381 * as well as to obtain loggers from an instance of that class.
1382 */
1383 static final RuntimePermission LOGGERFINDER_PERMISSION =
1384 new RuntimePermission("loggerFinder");
1385
1386 /**
1387 * Creates a new instance of {@code LoggerFinder}.
1388 *
1389 * @implNote It is recommended that a {@code LoggerFinder} service
1390 * implementation does not perform any heavy initialization in its
1391 * constructor, in order to avoid possible risks of deadlock or class
1392 * loading cycles during the instantiation of the service provider.
1393 *
1394 * @throws SecurityException if a security manager is present and its
1395 * {@code checkPermission} method doesn't allow the
1396 * {@code RuntimePermission("loggerFinder")}.
1397 */
1398 protected LoggerFinder() {
1399 this(checkPermission());
1400 }
1401
1402 private LoggerFinder(Void unused) {
1403 // nothing to do.
1404 }
1405
1406 private static Void checkPermission() {
1407 final SecurityManager sm = System.getSecurityManager();
1408 if (sm != null) {
1409 sm.checkPermission(LOGGERFINDER_PERMISSION);
1410 }
1411 return null;
1412 }
1413
1414 /**
1415 * Returns an instance of {@link Logger Logger}
1416 * for the given {@code caller}.
1417 *
1418 * @param name the name of the logger.
1419 * @param caller the class for which the logger is being requested;
1420 * can be {@code null}.
1421 *
1422 * @return a {@link Logger logger} suitable for the given caller's
1423 * use.
1424 * @throws NullPointerException if {@code name} is {@code null} or
1425 * {@code caller} is {@code null}.
1426 * @throws SecurityException if a security manager is present and its
1427 * {@code checkPermission} method doesn't allow the
1428 * {@code RuntimePermission("loggerFinder")}.
1429 */
1430 public abstract Logger getLogger(String name, /* Module */ Class<?> caller);
1431
1432 /**
1433 * Returns a localizable instance of {@link Logger Logger}
1434 * for the given {@code caller}.
1435 * The returned logger will use the provided resource bundle for
1436 * message localization.
1437 *
1438 * @implSpec By default, this method calls {@link
1439 * #getLogger(java.lang.String, java.lang.Class)
1440 * this.getLogger(name, caller)} to obtain a logger, then wraps that
1441 * logger in a {@link Logger} instance where all methods that do not
1442 * take a {@link ResourceBundle} as parameter are redirected to one
1443 * which does - passing the given {@code bundle} for
1444 * localization. So for instance, a call to {@link
1445 * Logger#log(Level, String) Logger.log(Level.INFO, msg)}
1446 * will end up as a call to {@link
1447 * Logger#log(Level, ResourceBundle, String, Object...)
1448 * Logger.log(Level.INFO, bundle, msg, (Object[])null)} on the wrapped
1449 * logger instance.
1450 * Note however that by default, string messages returned by {@link
1451 * java.util.function.Supplier Supplier<String>} will not be
1452 * localized, as it is assumed that such strings are messages which are
1453 * already constructed, rather than keys in a resource bundle.
1454 * <p>
1455 * An implementation of {@code LoggerFinder} may override this method,
1456 * for example, when the underlying logging backend provides its own
1457 * mechanism for localizing log messages, then such a
1458 * {@code LoggerFinder} would be free to return a logger
1459 * that makes direct use of the mechanism provided by the backend.
1460 *
1461 * @param name the name of the logger.
1462 * @param bundle a resource bundle; can be {@code null}.
1463 * @param caller the class for which the logger is being requested.
1464 * @return an instance of {@link Logger Logger} which will use the
1465 * provided resource bundle for message localization.
1466 *
1467 * @throws NullPointerException if {@code name} is {@code null} or
1468 * {@code caller} is {@code null}.
1469 * @throws SecurityException if a security manager is present and its
1470 * {@code checkPermission} method doesn't allow the
1471 * {@code RuntimePermission("loggerFinder")}.
1472 */
1473 public Logger getLocalizedLogger(String name, ResourceBundle bundle,
1474 /* Module */ Class<?> caller) {
1475 return new LocalizedLoggerWrapper<>(getLogger(name, caller), bundle);
1476 }
1477
1478 /**
1479 * Returns the {@code LoggerFinder} instance. There is one
1480 * single system-wide {@code LoggerFinder} instance in
1481 * the Java Runtime. See the class specification of how the
1482 * {@link LoggerFinder LoggerFinder} implementation is located and
1483 * loaded.
1484
1485 * @return the {@link LoggerFinder LoggerFinder} instance.
1486 * @throws SecurityException if a security manager is present and its
1487 * {@code checkPermission} method doesn't allow the
1488 * {@code RuntimePermission("loggerFinder")}.
1489 */
1490 public static LoggerFinder getLoggerFinder() {
1491 final SecurityManager sm = System.getSecurityManager();
1492 if (sm != null) {
1493 sm.checkPermission(LOGGERFINDER_PERMISSION);
1494 }
1495 return accessProvider();
1496 }
1497
1498
1499 private static volatile LoggerFinder service;
1500 static LoggerFinder accessProvider() {
1501 // We do not need to synchronize: LoggerFinderLoader will
1502 // always return the same instance, so if we don't have it,
1503 // just fetch it again.
1504 if (service == null) {
1505 PrivilegedAction<LoggerFinder> pa =
1506 () -> LoggerFinderLoader.getLoggerFinder();
1507 service = AccessController.doPrivileged(pa, null,
1508 LOGGERFINDER_PERMISSION);
1509 }
1510 return service;
1511 }
1512
1513 }
1514
1515
1516 /**
1517 * Returns an instance of {@link Logger Logger} for the caller's
1518 * use.
1519 *
1520 * @implSpec
1521 * Instances returned by this method route messages to loggers
1522 * obtained by calling {@link LoggerFinder#getLogger(java.lang.String, java.lang.Class)
1523 * LoggerFinder.getLogger(name, caller)}.
1524 *
1525 * @apiNote
1526 * This method may defer calling the {@link
1527 * LoggerFinder#getLogger(java.lang.String, java.lang.Class)
1528 * LoggerFinder.getLogger} method to create an actual logger supplied by
1529 * the logging backend, for instance, to allow loggers to be obtained during
1530 * the system initialization time.
1531 *
1532 * @param name the name of the logger.
1533 * @return an instance of {@link Logger} that can be used by the calling
1534 * class.
1535 * @throws NullPointerException if {@code name} is {@code null}.
1536 */
1537 @CallerSensitive
1538 public static Logger getLogger(String name) {
1539 Objects.requireNonNull(name);
1540 final Class<?> caller = Reflection.getCallerClass();
1541 return LazyLoggers.getLogger(name, caller);
1542 }
1543
1544 /**
1545 * Returns a localizable instance of {@link Logger
1546 * Logger} for the caller's use.
1547 * The returned logger will use the provided resource bundle for message
1548 * localization.
1549 *
1550 * @implSpec
1551 * The returned logger will perform message localization as specified
1552 * by {@link LoggerFinder#getLocalizedLogger(java.lang.String,
1553 * java.util.ResourceBundle, java.lang.Class)
1554 * LoggerFinder.getLocalizedLogger(name, bundle, caller}.
1555 *
1556 * @apiNote
1557 * This method is intended to be used after the system is fully initialized.
1558 * This method may trigger the immediate loading and initialization
1559 * of the {@link LoggerFinder} service, which may cause issues if the
1560 * Java Runtime is not ready to initialize the concrete service
1561 * implementation yet.
1562 * System classes which may be loaded early in the boot sequence and
1563 * need to log localized messages should create a logger using
1564 * {@link #getLogger(java.lang.String)} and then use the log methods that
1565 * take a resource bundle as parameter.
1566 *
1567 * @param name the name of the logger.
1568 * @param bundle a resource bundle.
1569 * @return an instance of {@link Logger} which will use the provided
1570 * resource bundle for message localization.
1571 * @throws NullPointerException if {@code name} is {@code null} or
1572 * {@code bundle} is {@code null}.
1573 */
1574 @CallerSensitive
1575 public static Logger getLogger(String name, ResourceBundle bundle) {
1576 final ResourceBundle rb = Objects.requireNonNull(bundle);
1577 Objects.requireNonNull(name);
1578 final Class<?> caller = Reflection.getCallerClass();
1579 final SecurityManager sm = System.getSecurityManager();
1580 // We don't use LazyLoggers if a resource bundle is specified.
1581 // Bootstrap sensitive classes in the JDK do not use resource bundles
1582 // when logging. This could be revisited later, if it needs to.
1583 if (sm != null) {
1584 return AccessController.doPrivileged((PrivilegedAction<Logger>)
1585 () -> LoggerFinder.accessProvider().getLocalizedLogger(name, rb, caller),
1586 null,
1587 LoggerFinder.LOGGERFINDER_PERMISSION);
1588 }
1589 return LoggerFinder.accessProvider().getLocalizedLogger(name, rb, caller);
1590 }
1591
1592 /**
1593 * Terminates the currently running Java Virtual Machine. The
1594 * argument serves as a status code; by convention, a nonzero status
1595 * code indicates abnormal termination.
1596 * <p>
1597 * This method calls the <code>exit</code> method in class
1598 * <code>Runtime</code>. This method never returns normally.
1599 * <p>
1600 * The call <code>System.exit(n)</code> is effectively equivalent to
1601 * the call:
1602 * <blockquote><pre>
1603 * Runtime.getRuntime().exit(n)
1604 * </pre></blockquote>
1605 *
1606 * @param status exit status.
1607 * @throws SecurityException
1608 * if a security manager exists and its <code>checkExit</code>
1609 * method doesn't allow exit with the specified status.
1610 * @see java.lang.Runtime#exit(int)
1611 */
1612 public static void exit(int status) {
|