From f9c321e6e976ee796af2902539b668ff1e76cdf4 Mon Sep 17 00:00:00 2001
From: "PSp..om" <PSpeed42@gmail.com>
Date: Fri, 8 Apr 2011 03:55:57 +0000
Subject: [PATCH] Reduced the scope of the synchronized block to something more
 reasonable (rather than essentially encompassing the entire application if
 you build your app around AppStates) but the realy benefit is now the app
 states can add/remove other app states without random oddness happening.
 ...and it's ever so slightly more efficient now, too.

git-svn-id: https://jmonkeyengine.googlecode.com/svn/trunk@7220 75d07b2b-3a1a-0410-a2c5-0572b91ccdca
---
 .../com/jme3/app/state/AppStateManager.java   | 69 ++++++++++---------
 1 file changed, 35 insertions(+), 34 deletions(-)

diff --git a/engine/src/core/com/jme3/app/state/AppStateManager.java b/engine/src/core/com/jme3/app/state/AppStateManager.java
index 4af07984b..6fe0e9c12 100644
--- a/engine/src/core/com/jme3/app/state/AppStateManager.java
+++ b/engine/src/core/com/jme3/app/state/AppStateManager.java
@@ -50,11 +50,21 @@ public class AppStateManager {
 
     private final ArrayList<AppState> states = new ArrayList<AppState>();
     private final Application app;
+    private AppState[] stateArray;
 
     public AppStateManager(Application app){
         this.app = app;
     }
 
+    protected AppState[] getArray(){
+        synchronized (states){
+            if (stateArray == null){
+                stateArray = states.toArray(new AppState[states.size()]);
+            }
+            return stateArray;
+        }
+    }
+
     /**
      * Attach a state to the AppStateManager, the same state cannot be attached
      * twice.
@@ -68,6 +78,7 @@ public class AppStateManager {
             if (!states.contains(state)){
                 state.stateAttached(this);
                 states.add(state);
+                stateArray = null;
                 return true;
             }else{
                 return false;
@@ -87,6 +98,7 @@ public class AppStateManager {
             if (states.contains(state)){
                 state.stateDetached(this);
                 states.remove(state);
+                stateArray = null;
                 return true;
             }else{
                 return false;
@@ -132,18 +144,15 @@ public class AppStateManager {
      * @param tpf Time per frame.
      */
     public void update(float tpf){
-        synchronized (states){
-            int num = states.size();
-            for (int i = 0; i < num; i++){
-                AppState state = states.get(i);
-                if (!state.isInitialized())
-                    state.initialize(this, app);
+        AppState[] array = getArray();
+        for (AppState state : array){
+            if (!state.isInitialized())
+                state.initialize(this, app);
 
-                if (state.isEnabled()) {
-                   state.update(tpf);
-                }
+            if (state.isEnabled()) {
+                state.update(tpf);
             }
-        } 
+        }
     }
 
     /**
@@ -151,16 +160,13 @@ public class AppStateManager {
      * @param rm The RenderManager
      */
     public void render(RenderManager rm){
-        synchronized (states){
-            int num = states.size();
-            for (int i = 0; i < num; i++){
-                AppState state = states.get(i);
-                if (!state.isInitialized())
-                    state.initialize(this, app);
+        AppState[] array = getArray();
+        for (AppState state : array){
+            if (!state.isInitialized())
+                state.initialize(this, app);
 
-                if (state.isEnabled()) {
-                   state.render(rm);
-                }
+            if (state.isEnabled()) {
+                state.render(rm);
             }
         }
     }
@@ -170,16 +176,13 @@ public class AppStateManager {
      * @param rm The RenderManager
      */
     public void postRender(){
-        synchronized (states){
-            int num = states.size();
-            for (int i = 0; i < num; i++){
-                AppState state = states.get(i);
-                if (!state.isInitialized())
-                    state.initialize(this, app);
+        AppState[] array = getArray();
+        for (AppState state : array){
+            if (!state.isInitialized())
+                state.initialize(this, app);
 
-                if (state.isEnabled()) {
-                   state.postRender();
-                }
+            if (state.isEnabled()) {
+                state.postRender();
             }
         }
     }
@@ -188,11 +191,9 @@ public class AppStateManager {
      * Calls cleanup on attached states, do not call directly.
      */
     public void cleanup(){
-        synchronized (states){
-            for (int i = 0; i < states.size(); i++){
-                AppState state = states.get(i);
-                state.cleanup();
-            }
+        AppState[] array = getArray();
+        for (AppState state : array){
+            state.cleanup();
         }
-    }
+    }    
 }