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Diffstat (limited to 'engine/src/core/com/jme3/app/state/AppStateManager.java')
| -rw-r--r-- | engine/src/core/com/jme3/app/state/AppStateManager.java | 288 |
1 files changed, 288 insertions, 0 deletions
diff --git a/engine/src/core/com/jme3/app/state/AppStateManager.java b/engine/src/core/com/jme3/app/state/AppStateManager.java new file mode 100644 index 0000000..81228af --- /dev/null +++ b/engine/src/core/com/jme3/app/state/AppStateManager.java @@ -0,0 +1,288 @@ +/*
+ * Copyright (c) 2009-2010 jMonkeyEngine
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * * Neither the name of 'jMonkeyEngine' nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+ * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+package com.jme3.app.state;
+
+import com.jme3.app.Application;
+import com.jme3.renderer.RenderManager;
+import com.jme3.util.SafeArrayList;
+import java.util.Arrays;
+import java.util.List;
+
+/**
+ * The <code>AppStateManager</code> holds a list of {@link AppState}s which
+ * it will update and render.<br/>
+ * When an {@link AppState} is attached or detached, the
+ * {@link AppState#stateAttached(com.jme3.app.state.AppStateManager) } and
+ * {@link AppState#stateDetached(com.jme3.app.state.AppStateManager) } methods
+ * will be called respectively.
+ *
+ * <p>The lifecycle for an attached AppState is as follows:</p>
+ * <ul>
+ * <li>stateAttached() : called when the state is attached on the thread on which
+ * the state was attached.
+ * <li>initialize() : called ONCE on the render thread at the beginning of the next
+ * AppStateManager.update().
+ * <li>stateDetached() : called when the state is attached on the thread on which
+ * the state was detached. This is not necessarily on the
+ * render thread and it is not necessarily safe to modify
+ * the scene graph, etc..
+ * <li>cleanup() : called ONCE on the render thread at the beginning of the next update
+ * after the state has been detached or when the application is
+ * terminating.
+ * </ul>
+ *
+ * @author Kirill Vainer, Paul Speed
+ */
+public class AppStateManager {
+
+ /**
+ * List holding the attached app states that are pending
+ * initialization. Once initialized they will be added to
+ * the running app states.
+ */
+ private final SafeArrayList<AppState> initializing = new SafeArrayList<AppState>(AppState.class);
+
+ /**
+ * Holds the active states once they are initialized.
+ */
+ private final SafeArrayList<AppState> states = new SafeArrayList<AppState>(AppState.class);
+
+ /**
+ * List holding the detached app states that are pending
+ * cleanup.
+ */
+ private final SafeArrayList<AppState> terminating = new SafeArrayList<AppState>(AppState.class);
+
+ // All of the above lists need to be thread safe but access will be
+ // synchronized separately.... but always on the states list. This
+ // is to avoid deadlocking that may occur and the most common use case
+ // is that they are all modified from the same thread anyway.
+
+ private final Application app;
+ private AppState[] stateArray;
+
+ public AppStateManager(Application app){
+ this.app = app;
+ }
+
+ protected AppState[] getInitializing() {
+ synchronized (states){
+ return initializing.getArray();
+ }
+ }
+
+ protected AppState[] getTerminating() {
+ synchronized (states){
+ return terminating.getArray();
+ }
+ }
+
+ protected AppState[] getStates(){
+ synchronized (states){
+ return states.getArray();
+ }
+ }
+
+ /**
+ * Attach a state to the AppStateManager, the same state cannot be attached
+ * twice.
+ *
+ * @param state The state to attach
+ * @return True if the state was successfully attached, false if the state
+ * was already attached.
+ */
+ public boolean attach(AppState state){
+ synchronized (states){
+ if (!states.contains(state) && !initializing.contains(state)){
+ state.stateAttached(this);
+ initializing.add(state);
+ return true;
+ }else{
+ return false;
+ }
+ }
+ }
+
+ /**
+ * Detaches the state from the AppStateManager.
+ *
+ * @param state The state to detach
+ * @return True if the state was detached successfully, false
+ * if the state was not attached in the first place.
+ */
+ public boolean detach(AppState state){
+ synchronized (states){
+ if (states.contains(state)){
+ state.stateDetached(this);
+ states.remove(state);
+ terminating.add(state);
+ return true;
+ } else if(initializing.contains(state)){
+ state.stateDetached(this);
+ initializing.remove(state);
+ return true;
+ }else{
+ return false;
+ }
+ }
+ }
+
+ /**
+ * Check if a state is attached or not.
+ *
+ * @param state The state to check
+ * @return True if the state is currently attached to this AppStateManager.
+ *
+ * @see AppStateManager#attach(com.jme3.app.state.AppState)
+ */
+ public boolean hasState(AppState state){
+ synchronized (states){
+ return states.contains(state) || initializing.contains(state);
+ }
+ }
+
+ /**
+ * Returns the first state that is an instance of subclass of the specified class.
+ * @param <T>
+ * @param stateClass
+ * @return First attached state that is an instance of stateClass
+ */
+ public <T extends AppState> T getState(Class<T> stateClass){
+ synchronized (states){
+ AppState[] array = getStates();
+ for (AppState state : array) {
+ if (stateClass.isAssignableFrom(state.getClass())){
+ return (T) state;
+ }
+ }
+
+ // This may be more trouble than its worth but I think
+ // it's necessary for proper decoupling of states and provides
+ // similar behavior to before where a state could be looked
+ // up even if it wasn't initialized. -pspeed
+ array = getInitializing();
+ for (AppState state : array) {
+ if (stateClass.isAssignableFrom(state.getClass())){
+ return (T) state;
+ }
+ }
+ }
+ return null;
+ }
+
+ protected void initializePending(){
+ AppState[] array = getInitializing();
+ synchronized( states ) {
+ // Move the states that will be initialized
+ // into the active array. In all but one case the
+ // order doesn't matter but if we do this here then
+ // a state can detach itself in initialize(). If we
+ // did it after then it couldn't.
+ List<AppState> transfer = Arrays.asList(array);
+ states.addAll(transfer);
+ initializing.removeAll(transfer);
+ }
+ for (AppState state : array) {
+ state.initialize(this, app);
+ }
+ }
+
+ protected void terminatePending(){
+ AppState[] array = getTerminating();
+ for (AppState state : array) {
+ state.cleanup();
+ }
+ synchronized( states ) {
+ // Remove just the states that were terminated...
+ // which might now be a subset of the total terminating
+ // list.
+ terminating.removeAll(Arrays.asList(array));
+ }
+ }
+
+ /**
+ * Calls update for attached states, do not call directly.
+ * @param tpf Time per frame.
+ */
+ public void update(float tpf){
+
+ // Cleanup any states pending
+ terminatePending();
+
+ // Initialize any states pending
+ initializePending();
+
+ // Update enabled states
+ AppState[] array = getStates();
+ for (AppState state : array){
+ if (state.isEnabled()) {
+ state.update(tpf);
+ }
+ }
+ }
+
+ /**
+ * Calls render for all attached and initialized states, do not call directly.
+ * @param rm The RenderManager
+ */
+ public void render(RenderManager rm){
+ AppState[] array = getStates();
+ for (AppState state : array){
+ if (state.isEnabled()) {
+ state.render(rm);
+ }
+ }
+ }
+
+ /**
+ * Calls render for all attached and initialized states, do not call directly.
+ */
+ public void postRender(){
+ AppState[] array = getStates();
+ for (AppState state : array){
+ if (state.isEnabled()) {
+ state.postRender();
+ }
+ }
+ }
+
+ /**
+ * Calls cleanup on attached states, do not call directly.
+ */
+ public void cleanup(){
+ AppState[] array = getStates();
+ for (AppState state : array){
+ state.cleanup();
+ }
+ }
+}
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