diff options
| -rw-r--r-- | server/src/com/vaadin/util/CurrentInstance.java | 94 |
1 files changed, 40 insertions, 54 deletions
diff --git a/server/src/com/vaadin/util/CurrentInstance.java b/server/src/com/vaadin/util/CurrentInstance.java index 00d2e7346d..6f2c0a2eca 100644 --- a/server/src/com/vaadin/util/CurrentInstance.java +++ b/server/src/com/vaadin/util/CurrentInstance.java @@ -1,12 +1,12 @@ /* * Copyright 2000-2014 Vaadin Ltd. - * + * * Licensed under the Apache License, Version 2.0 (the "License"); you may not * use this file except in compliance with the License. You may obtain a copy of * the License at - * + * * http://www.apache.org/licenses/LICENSE-2.0 - * + * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the @@ -52,12 +52,14 @@ import com.vaadin.ui.UI; * <p> * Non-inheritable: {@link VaadinRequest}, {@link VaadinResponse}. * </p> - * + * * @author Vaadin Ltd * @since 7.0.0 */ public class CurrentInstance implements Serializable { private static final Object NULL_OBJECT = new Object(); + private static final CurrentInstance CURRENT_INSTANCE_NULL = new CurrentInstance( + NULL_OBJECT, true); private final WeakReference<Object> instance; private final boolean inheritable; @@ -90,7 +92,7 @@ public class CurrentInstance implements Serializable { /** * Gets the current instance of a specific type if available. - * + * * @param type * the class to get an instance of * @return the current instance or the provided type, or <code>null</code> @@ -110,7 +112,7 @@ public class CurrentInstance implements Serializable { * ThreadLocal should only outlive the referenced object on * threads that are not doing anything related to Vaadin, which * should thus never invoke CurrentInstance.get(). - * + * * At this point, there might also be other values that have * been collected, so we'll scan the entire map and remove stale * CurrentInstance objects. Using a ReferenceQueue could make @@ -148,10 +150,10 @@ public class CurrentInstance implements Serializable { /** * Sets the current instance of the given type. - * + * * @see #setInheritable(Class, Object) * @see ThreadLocal - * + * * @param type * the class that should be used when getting the current * instance back @@ -167,10 +169,10 @@ public class CurrentInstance implements Serializable { * instance that is inheritable will be available for child threads and in * code run by {@link VaadinSession#access(Runnable)} and * {@link UI#access(Runnable)}. - * + * * @see #set(Class, Object) * @see InheritableThreadLocal - * + * * @param type * the class that should be used when getting the current * instance back @@ -181,17 +183,18 @@ public class CurrentInstance implements Serializable { set(type, instance, true); } - private static <T> void set(Class<T> type, T instance, boolean inheritable) { + private static <T> CurrentInstance set(Class<T> type, T instance, + boolean inheritable) { Map<Class<?>, CurrentInstance> map = instances.get(); + CurrentInstance previousInstance = null; if (instance == null) { // remove the instance - if (map == null) { - return; - } - map.remove(type); - if (map.isEmpty()) { - instances.remove(); - map = null; + if (map != null) { + previousInstance = map.remove(type); + if (map.isEmpty()) { + instances.remove(); + map = null; + } } } else { assert type.isInstance(instance) : "Invald instance type"; @@ -200,8 +203,8 @@ public class CurrentInstance implements Serializable { instances.set(map); } - CurrentInstance previousInstance = map.put(type, - new CurrentInstance(instance, inheritable)); + previousInstance = map.put(type, new CurrentInstance(instance, + inheritable)); if (previousInstance != null) { assert previousInstance.inheritable == inheritable : "Inheritable status mismatch for " + type @@ -211,6 +214,10 @@ public class CurrentInstance implements Serializable { + inheritable + ")"; } } + if (previousInstance == null) { + previousInstance = CURRENT_INSTANCE_NULL; + } + return previousInstance; } /** @@ -223,9 +230,9 @@ public class CurrentInstance implements Serializable { /** * Restores the given instances to the given values. Note that this should * only be used internally to restore Vaadin classes. - * + * * @since 7.1 - * + * * @param old * A Class -> CurrentInstance map to set as current instances */ @@ -243,7 +250,7 @@ public class CurrentInstance implements Serializable { * CurrentInstance. Without this a reference to an already * collected instance may be left in the CurrentInstance when it * really should be restored to null. - * + * * One example case that this fixes: * VaadinService.runPendingAccessTasks() clears all current * instances and then sets everything but the UI. This makes @@ -267,9 +274,9 @@ public class CurrentInstance implements Serializable { /** * Gets the currently set instances so that they can later be restored using * {@link #restoreInstances(Map)}. - * + * * @since 7.1 - * + * * @param onlyInheritable * <code>true</code> if only the inheritable instances should be * included; <code>false</code> to get all instances. @@ -305,20 +312,17 @@ public class CurrentInstance implements Serializable { * Sets current instances for the UI and all related classes. The previously * defined values can be restored by passing the returned map to * {@link #restoreInstances(Map)}. - * + * * @since 7.1 - * + * * @param ui * The UI * @return A map containing the old values of the instances that this method * updated. */ public static Map<Class<?>, CurrentInstance> setCurrent(UI ui) { - Map<Class<?>, CurrentInstance> old = new HashMap<Class<?>, CurrentInstance>(); - old.put(UI.class, - new CurrentInstance(getSameOrNullObject(UI.getCurrent()), true)); - UI.setCurrent(ui); - old.putAll(setCurrent(ui.getSession())); + Map<Class<?>, CurrentInstance> old = setCurrent(ui.getSession()); + old.put(UI.class, set(UI.class, ui, true)); return old; } @@ -326,9 +330,9 @@ public class CurrentInstance implements Serializable { * Sets current instances for the {@link VaadinSession} and all related * classes. The previously defined values can be restored by passing the * returned map to {@link #restoreInstances(Map)}. - * + * * @since 7.1 - * + * * @param session * The VaadinSession * @return A map containing the old values of the instances this method @@ -337,33 +341,15 @@ public class CurrentInstance implements Serializable { public static Map<Class<?>, CurrentInstance> setCurrent( VaadinSession session) { Map<Class<?>, CurrentInstance> old = new HashMap<Class<?>, CurrentInstance>(); - old.put(VaadinSession.class, new CurrentInstance( - getSameOrNullObject(VaadinSession.getCurrent()), true)); - old.put(VaadinService.class, new CurrentInstance( - getSameOrNullObject(VaadinService.getCurrent()), true)); + old.put(VaadinSession.class, set(VaadinSession.class, session, true)); VaadinService service = null; if (session != null) { service = session.getService(); } - - VaadinSession.setCurrent(session); - VaadinService.setCurrent(service); - + old.put(VaadinService.class, set(VaadinService.class, service, true)); return old; } - /** - * Returns {@code object} unless it is null, in which case #NULL_OBJECT is - * returned. - * - * @param object - * The instance to return if non-null. - * @return {@code object} or #NULL_OBJECT if {@code object} is null. - */ - private static Object getSameOrNullObject(Object object) { - return object == null ? NULL_OBJECT : object; - } - private static Logger getLogger() { return Logger.getLogger(CurrentInstance.class.getName()); } |