CompositeSubscription memory reduction

akarnokd · akarnokd · commit 8ff7d40704d4 · 2014-02-05T21:39:53.000+01:00
diff --git a/rxjava-core/src/main/java/rx/subscriptions/CompositeSubscription.java b/rxjava-core/src/main/java/rx/subscriptions/CompositeSubscription.java
@@ -17,7 +17,6 @@
 
 import java.util.ArrayList;
 import java.util.Arrays;
-import java.util.Collection;
 import java.util.List;
 import java.util.concurrent.atomic.AtomicReference;
 
@@ -34,7 +33,15 @@ public final class CompositeSubscription implements Subscription {
 
     private final AtomicReference<State> state = new AtomicReference<State>();
 
-    private static final State CLEAR_STATE = new State(false, new Subscription[0]);
+    /** Empty initial state. */
+    private static final State CLEAR_STATE;
+    /** Unsubscribed empty state. */
+    private static final State CLEAR_STATE_UNSUBSCRIBED;
+    static {
+        Subscription[] s0 = new Subscription[0];
+        CLEAR_STATE = new State(false, s0);
+        CLEAR_STATE_UNSUBSCRIBED = new State(true, s0);
+    }
 
     private static final class State {
         final boolean isUnsubscribed;
@@ -46,7 +53,7 @@ private static final class State {
         }
 
         State unsubscribe() {
-            return new State(true, subscriptions);
+            return CLEAR_STATE_UNSUBSCRIBED;
         }
 
         State add(Subscription s) {
@@ -66,7 +73,7 @@ State remove(Subscription s) {
         }
 
         State clear() {
-            return new State(isUnsubscribed, new Subscription[0]);
+            return isUnsubscribed ? CLEAR_STATE_UNSUBSCRIBED : CLEAR_STATE;
         }
     }
 
@@ -78,6 +85,7 @@ public CompositeSubscription(final Subscription... subscriptions) {
         state.set(new State(false, subscriptions));
     }
 
+    @Override
     public boolean isUnsubscribed() {
         return state.get().isUnsubscribed;
     }

Original file line number	Diff line number	Diff line change
`@@ -17,7 +17,6 @@`
`17`	`17`
`18`	`18`	`import java.util.ArrayList;`
`19`	`19`	`import java.util.Arrays;`
`20`		`-import java.util.Collection;`
`21`	`20`	`import java.util.List;`
`22`	`21`	`import java.util.concurrent.atomic.AtomicReference;`
`23`	`22`
`@@ -34,7 +33,15 @@ public final class CompositeSubscription implements Subscription {`
`34`	`33`
`35`	`34`	`private final AtomicReference<State> state = new AtomicReference<State>();`
`36`	`35`
`37`		`- private static final State CLEAR_STATE = new State(false, new Subscription[0]);`
	`36`	`+ /** Empty initial state. */`
	`37`	`+ private static final State CLEAR_STATE;`
	`38`	`+ /** Unsubscribed empty state. */`
	`39`	`+ private static final State CLEAR_STATE_UNSUBSCRIBED;`
	`40`	`+ static {`
	`41`	`+ Subscription[] s0 = new Subscription[0];`
	`42`	`+ CLEAR_STATE = new State(false, s0);`
	`43`	`+ CLEAR_STATE_UNSUBSCRIBED = new State(true, s0);`
	`44`	`+ }`
`38`	`45`
`39`	`46`	`private static final class State {`
`40`	`47`	`final boolean isUnsubscribed;`
`@@ -46,7 +53,7 @@ private static final class State {`
`46`	`53`	`}`
`47`	`54`
`48`	`55`	`State unsubscribe() {`
`49`		`- return new State(true, subscriptions);`
	`56`	`+ return CLEAR_STATE_UNSUBSCRIBED;`
`50`	`57`	`}`
`51`	`58`
`52`	`59`	`State add(Subscription s) {`
`@@ -66,7 +73,7 @@ State remove(Subscription s) {`
`66`	`73`	`}`
`67`	`74`
`68`	`75`	`State clear() {`
`69`		`- return new State(isUnsubscribed, new Subscription[0]);`
	`76`	`+ return isUnsubscribed ? CLEAR_STATE_UNSUBSCRIBED : CLEAR_STATE;`
`70`	`77`	`}`
`71`	`78`	`}`
`72`	`79`
`@@ -78,6 +85,7 @@ public CompositeSubscription(final Subscription... subscriptions) {`
`78`	`85`	`state.set(new State(false, subscriptions));`
`79`	`86`	`}`
`80`	`87`
	`88`	`+ @Override`
`81`	`89`	`public boolean isUnsubscribed() {`
`82`	`90`	`return state.get().isUnsubscribed;`
`83`	`91`	`}`