jdk-sandbox: comparison jdk/src/java.logging/share/classes/java/util/logging/Level.java

equal deleted inserted replaced

-:46cd6d4f353f
+:dba53de83476
 /*
-* Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved.
+* Copyright (c) 2000, 2016, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */
 package java.util.logging;
+import java.lang.ref.Reference;
+import java.lang.ref.ReferenceQueue;
+import java.lang.ref.WeakReference;
 import java.lang.reflect.Module;
+import java.security.AccessController;
+import java.security.PrivilegedAction;
 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Locale;
 import java.util.Map;
+import java.util.Optional;
 import java.util.ResourceBundle;
+import java.util.function.Function;
+import jdk.internal.loader.ClassLoaderValue;
 /**
 * The Level class defines a set of standard logging levels that
 * can be used to control logging output.  The logging Level objects
 * are ordered and are specified by ordered integers.  Enabling logging
 * ALL indicates that all messages should be logged.
 * This level is initialized to <CODE>Integer.MIN_VALUE</CODE>.
 */
 public static final Level ALL = new Level("ALL", Integer.MIN_VALUE, defaultBundle);
+private static final Level[] standardLevels = {
+OFF, SEVERE, WARNING, INFO, CONFIG, FINE, FINER, FINEST, ALL
+};
 /**
 * Create a named Level with a given integer value.
 * <p>
 * Note that this constructor is "protected" to allow subclassing.
 * In general clients of logging should use one of the constant Level
 private String computeLocalizedLevelName(Locale newLocale) {
 // Resource bundle should be loaded from the defining module
 // or its defining class loader, if it's unnamed module,
 // of this Level instance that can be a custom Level subclass;
 Module module = this.getClass().getModule();
-ResourceBundle rb = ResourceBundle.getBundle(resourceBundleName, newLocale, module);
+ResourceBundle rb = ResourceBundle.getBundle(resourceBundleName,
+newLocale, module);
 final String localizedName = rb.getString(name);
 final boolean isDefaultBundle = defaultBundle.equals(resourceBundleName);
 if (!isDefaultBundle) return localizedName;
 static Level findLevel(String name) {
 if (name == null) {
 throw new NullPointerException();
 }
-KnownLevel level;
+Optional<Level> level;
 // Look for a known Level with the given non-localized name.
-level = KnownLevel.findByName(name);
+level = KnownLevel.findByName(name, KnownLevel::mirrored);
-if (level != null) {
+if (level.isPresent()) {
-return level.mirroredLevel;
+return level.get();
 }
 // Now, check if the given name is an integer.  If so,
 // first look for a Level with the given value and then
 // if necessary create one.
 try {
 int x = Integer.parseInt(name);
-level = KnownLevel.findByValue(x);
+level = KnownLevel.findByValue(x, KnownLevel::mirrored);
-if (level == null) {
+if (!level.isPresent()) {
 // add new Level
 Level levelObject = new Level(name, x);
-level = KnownLevel.findByValue(x);
+// There's no need to use a reachability fence here because
-}
+// KnownLevel keeps a strong reference on the level when
-return level.mirroredLevel;
+// level.getClass() == Level.class.
+return KnownLevel.findByValue(x, KnownLevel::mirrored).get();
+}
 } catch (NumberFormatException ex) {
 // Not an integer.
 // Drop through.
 }
-level = KnownLevel.findByLocalizedLevelName(name);
+level = KnownLevel.findByLocalizedLevelName(name,
-if (level != null) {
+KnownLevel::mirrored);
-return level.mirroredLevel;
+if (level.isPresent()) {
+return level.get();
 }
 return null;
 }
 private static final long serialVersionUID = -8176160795706313070L;
 // Serialization magic to prevent "doppelgangers".
 // This is a performance optimization.
 private Object readResolve() {
-KnownLevel o = KnownLevel.matches(this);
+Optional<Level> level = KnownLevel.matches(this);
-if (o != null) {
+if (level.isPresent()) {
-return o.levelObject;
+return level.get();
 }
 // Woops.  Whoever sent us this object knows
 // about a new log level.  Add it to our list.
-Level level = new Level(this.name, this.value, this.resourceBundleName);
+return new Level(this.name, this.value, this.resourceBundleName);
-return level;
 }
 /**
 * Parse a level name string into a Level.
 * <p>
 */
 public static synchronized Level parse(String name) throws IllegalArgumentException {
 // Check that name is not null.
 name.length();
-KnownLevel level;
+Optional<Level> level;
 // Look for a known Level with the given non-localized name.
-level = KnownLevel.findByName(name);
+level = KnownLevel.findByName(name, KnownLevel::referent);
-if (level != null) {
+if (level.isPresent()) {
-return level.levelObject;
+return level.get();
 }
 // Now, check if the given name is an integer.  If so,
 // first look for a Level with the given value and then
 // if necessary create one.
 try {
 int x = Integer.parseInt(name);
-level = KnownLevel.findByValue(x);
+level = KnownLevel.findByValue(x, KnownLevel::referent);
-if (level == null) {
+if (level.isPresent()) {
-// add new Level
+return level.get();
-Level levelObject = new Level(name, x);
+}
-level = KnownLevel.findByValue(x);
+// add new Level.
-}
+Level levelObject = new Level(name, x);
-return level.levelObject;
+// There's no need to use a reachability fence here because
+// KnownLevel keeps a strong reference on the level when
+// level.getClass() == Level.class.
+return KnownLevel.findByValue(x, KnownLevel::referent).get();
 } catch (NumberFormatException ex) {
 // Not an integer.
 // Drop through.
 }
 // Finally, look for a known level with the given localized name,
 // in the current default locale.
 // This is relatively expensive, but not excessively so.
-level = KnownLevel.findByLocalizedLevelName(name);
+level = KnownLevel.findByLocalizedLevelName(name, KnownLevel::referent);
-if (level != null) {
+if (level .isPresent()) {
-return level.levelObject;
+return level.get();
 }
 // OK, we've tried everything and failed
 throw new IllegalArgumentException("Bad level \"" + name + "\"");
 }
 //
 // Implementation Notes:
 // If Level.getName, Level.getLocalizedName, Level.getResourceBundleName methods
 // were final, the following KnownLevel implementation can be removed.
 // Future API change should take this into consideration.
-static final class KnownLevel {
+static final class KnownLevel extends WeakReference<Level> {
 private static Map<String, List<KnownLevel>> nameToLevels = new HashMap<>();
 private static Map<Integer, List<KnownLevel>> intToLevels = new HashMap<>();
-final Level levelObject;     // instance of Level class or Level subclass
+private static final ReferenceQueue<Level> QUEUE = new ReferenceQueue<>();
+// CUSTOM_LEVEL_CLV is used to register custom level instances with
+// their defining class loader, so that they are garbage collected
+// if and only if their class loader is no longer strongly
+// referenced.
+private static final ClassLoaderValue<List<Level>> CUSTOM_LEVEL_CLV =
+new ClassLoaderValue<>();
 final Level mirroredLevel;   // mirror of the custom Level
 KnownLevel(Level l) {
-this.levelObject = l;
+super(l, QUEUE);
 if (l.getClass() == Level.class) {
 this.mirroredLevel = l;
 } else {
 // this mirrored level object is hidden
-this.mirroredLevel = new Level(l.name, l.value, l.resourceBundleName, false);
+this.mirroredLevel = new Level(l.name, l.value,
-}
+l.resourceBundleName, false);
+}
+}
+Optional<Level> mirrored() {
+return Optional.of(mirroredLevel);
+}
+Optional<Level> referent() {
+return Optional.ofNullable(get());
+}
+private void remove() {
+Optional.ofNullable(nameToLevels.get(mirroredLevel.name))
+.ifPresent((x) -> x.remove(this));
+Optional.ofNullable(intToLevels.get(mirroredLevel.value))
+.ifPresent((x) -> x.remove(this));
+}
+// Remove all stale KnownLevel instances
+static synchronized void purge() {
+Reference<? extends Level> ref;
+while ((ref = QUEUE.poll()) != null) {
+if (ref instanceof KnownLevel) {
+((KnownLevel)ref).remove();
+}
+}
+}
+private static void registerWithClassLoader(Level customLevel) {
+PrivilegedAction<ClassLoader> pa =
+() -> customLevel.getClass().getClassLoader();
+PrivilegedAction<String> pn =  customLevel.getClass()::getName;
+final String name = AccessController.doPrivileged(pn);
+final ClassLoader cl = AccessController.doPrivileged(pa);
+CUSTOM_LEVEL_CLV.computeIfAbsent(cl, (c, v) -> new ArrayList<>())
+.add(customLevel);
 }
 static synchronized void add(Level l) {
+purge();
 // the mirroredLevel object is always added to the list
 // before the custom Level instance
 KnownLevel o = new KnownLevel(l);
 List<KnownLevel> list = nameToLevels.get(l.name);
 if (list == null) {
 if (list == null) {
 list = new ArrayList<>();
 intToLevels.put(l.value, list);
 }
 list.add(o);
+// keep the custom level reachable from its class loader
+// This will ensure that custom level values are not GC'ed
+// until there class loader is GC'ed.
+if (o.mirroredLevel != l) {
+registerWithClassLoader(l);
+}
 }
 // Returns a KnownLevel with the given non-localized name.
-static synchronized KnownLevel findByName(String name) {
+static synchronized Optional<Level> findByName(String name,
-List<KnownLevel> list = nameToLevels.get(name);
+Function<KnownLevel, Optional<Level>> selector) {
-if (list != null) {
+purge();
-return list.get(0);
+return nameToLevels.getOrDefault(name, Collections.emptyList())
-}
+.stream()
-return null;
+.map(selector)
+.flatMap(Optional::stream)
+.findFirst();
 }
 // Returns a KnownLevel with the given value.
-static synchronized KnownLevel findByValue(int value) {
+static synchronized Optional<Level> findByValue(int value,
-List<KnownLevel> list = intToLevels.get(value);
+Function<KnownLevel, Optional<Level>> selector) {
-if (list != null) {
+purge();
-return list.get(0);
+return intToLevels.getOrDefault(value, Collections.emptyList())
-}
+.stream()
-return null;
+.map(selector)
+.flatMap(Optional::stream)
+.findFirst();
 }
 // Returns a KnownLevel with the given localized name matching
 // by calling the Level.getLocalizedLevelName() method (i.e. found
 // from the resourceBundle associated with the Level object).
 // This method does not call Level.getLocalizedName() that may
 // be overridden in a subclass implementation
-static synchronized KnownLevel findByLocalizedLevelName(String name) {
+static synchronized Optional<Level> findByLocalizedLevelName(String name,
-for (List<KnownLevel> levels : nameToLevels.values()) {
+Function<KnownLevel, Optional<Level>> selector) {
-for (KnownLevel l : levels) {
+purge();
-String lname = l.levelObject.getLocalizedLevelName();
+return nameToLevels.values().stream()
-if (name.equals(lname)) {
+.flatMap(List::stream)
-return l;
+.map(selector)
-}
+.flatMap(Optional::stream)
-}
+.filter(l -> name.equals(l.getLocalizedLevelName()))
-}
+.findFirst();
-return null;
+}
-}
+static synchronized Optional<Level> matches(Level l) {
-static synchronized KnownLevel matches(Level l) {
+purge();
 List<KnownLevel> list = nameToLevels.get(l.name);
 if (list != null) {
-for (KnownLevel level : list) {
+for (KnownLevel ref : list) {
-Level other = level.mirroredLevel;
+Level levelObject = ref.get();
+if (levelObject == null) continue;
+Level other = ref.mirroredLevel;
 if (l.value == other.value &&
 (l.resourceBundleName == other.resourceBundleName ||
 (l.resourceBundleName != null &&
 l.resourceBundleName.equals(other.resourceBundleName)))) {
-return level;
+return Optional.of(levelObject);
 }
 }
 }
-return null;
+return Optional.empty();
 }
 }
 }

changeset 40944	dba53de83476
parent 36511	9d0388c6b336
child 42338	a60f280f803c