diff --git a/core/java/android/content/Intent.java b/core/java/android/content/Intent.java
index 6e3663e..e7b96e7 100644
--- a/core/java/android/content/Intent.java
+++ b/core/java/android/content/Intent.java
@@ -2794,7 +2794,7 @@
      * @param action The Intent action, such as ACTION_VIEW.
      */
     public Intent(String action) {
-        mAction = action;
+        setAction(action);
     }
 
     /**
@@ -2814,7 +2814,7 @@
      * @param uri The Intent data URI.
      */
     public Intent(String action, Uri uri) {
-        mAction = action;
+        setAction(action);
         mData = uri;
     }
 
@@ -2863,7 +2863,7 @@
      */
     public Intent(String action, Uri uri,
             Context packageContext, Class<?> cls) {
-        mAction = action;
+        setAction(action);
         mData = uri;
         mComponent = new ComponentName(packageContext, cls);
     }
@@ -2985,7 +2985,7 @@
 
                 // action
                 if (uri.startsWith("action=", i)) {
-                    intent.mAction = value;
+                    intent.setAction(value);
                 }
 
                 // categories
@@ -4061,7 +4061,7 @@
      * @see #getAction
      */
     public Intent setAction(String action) {
-        mAction = action;
+        mAction = action != null ? action.intern() : null;
         return this;
     }
 
@@ -4165,7 +4165,7 @@
         if (mCategories == null) {
             mCategories = new HashSet<String>();
         }
-        mCategories.add(category);
+        mCategories.add(category.intern());
         return this;
     }
 
@@ -5678,7 +5678,7 @@
     }
 
     public void readFromParcel(Parcel in) {
-        mAction = in.readString();
+        setAction(in.readString());
         mData = Uri.CREATOR.createFromParcel(in);
         mType = in.readString();
         mFlags = in.readInt();
@@ -5694,7 +5694,7 @@
             mCategories = new HashSet<String>();
             int i;
             for (i=0; i<N; i++) {
-                mCategories.add(in.readString());
+                mCategories.add(in.readString().intern());
             }
         } else {
             mCategories = null;
diff --git a/core/java/android/content/IntentFilter.java b/core/java/android/content/IntentFilter.java
index 452fd8a..61d7424 100644
--- a/core/java/android/content/IntentFilter.java
+++ b/core/java/android/content/IntentFilter.java
@@ -461,7 +461,7 @@
      * @return True if the action is explicitly mentioned in the filter.
      */
     public final boolean hasAction(String action) {
-        return mActions.contains(action);
+        return action != null && mActions.contains(action);
     }
 
     /**
@@ -470,14 +470,10 @@
      *
      * @param action The desired action to look for.
      *
-     * @return True if the action is listed in the filter or the filter does
-     *         not specify any actions.
+     * @return True if the action is listed in the filter.
      */
     public final boolean matchAction(String action) {
-        if (action == null || mActions == null || mActions.size() == 0) {
-            return false;
-        }
-        return mActions.contains(action);
+        return hasAction(action);
     }
 
     /**
@@ -818,9 +814,9 @@
         if (mDataPaths == null) {
             return false;
         }
-        Iterator<PatternMatcher> i = mDataPaths.iterator();
-        while (i.hasNext()) {
-            final PatternMatcher pe = i.next();
+        final int numDataPaths = mDataPaths.size();
+        for (int i = 0; i < numDataPaths; i++) {
+            final PatternMatcher pe = mDataPaths.get(i);
             if (pe.match(data)) {
                 return true;
             }
@@ -849,9 +845,9 @@
         if (mDataAuthorities == null) {
             return NO_MATCH_DATA;
         }
-        Iterator<AuthorityEntry> i = mDataAuthorities.iterator();
-        while (i.hasNext()) {
-            final AuthorityEntry ae = i.next();
+        final int numDataAuthorities = mDataAuthorities.size();
+        for (int i = 0; i < numDataAuthorities; i++) {
+            final AuthorityEntry ae = mDataAuthorities.get(i);
             int match = ae.match(data);
             if (match >= 0) {
                 return match;
@@ -1098,7 +1094,7 @@
      */
     public final int match(String action, String type, String scheme,
             Uri data, Set<String> categories, String logTag) {
-        if (action != null && !matchAction(action)) {
+        if (!matchAction(action)) {
             if (Config.LOGV) Log.v(
                 logTag, "No matching action " + action + " for " + this);
             return NO_MATCH_ACTION;
@@ -1119,11 +1115,11 @@
             return dataMatch;
         }
 
-        String categoryMatch = matchCategories(categories);
-        if (categoryMatch != null) {
-            if (Config.LOGV) Log.v(
-                logTag, "No matching category "
-                + categoryMatch + " for " + this);
+        String categoryMismatch = matchCategories(categories);
+        if (categoryMismatch != null) {
+            if (Config.LOGV) {
+                Log.v(logTag, "No matching category " + categoryMismatch + " for " + this);
+            }
             return NO_MATCH_CATEGORY;
         }
 
@@ -1469,9 +1465,9 @@
             if (typeLength == slashpos+2 && type.charAt(slashpos+1) == '*') {
                 // Need to look through all types for one that matches
                 // our base...
-                final Iterator<String> it = t.iterator();
-                while (it.hasNext()) {
-                    String v = it.next();
+                final int numTypes = t.size();
+                for (int i = 0; i < numTypes; i++) {
+                    final String v = t.get(i);
                     if (type.regionMatches(0, v, 0, slashpos+1)) {
                         return true;
                     }
diff --git a/core/java/android/util/FastImmutableArraySet.java b/core/java/android/util/FastImmutableArraySet.java
new file mode 100644
index 0000000..4175c605
--- /dev/null
+++ b/core/java/android/util/FastImmutableArraySet.java
@@ -0,0 +1,78 @@
+/*
+ * Copyright (C) 2011 The Android Open Source Project
+ *
+ * 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 License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.util;
+
+import java.util.AbstractSet;
+import java.util.Iterator;
+
+/**
+ * A fast immutable set wrapper for an array that is optimized for non-concurrent iteration.
+ * The same iterator instance is reused each time to avoid creating lots of garbage.
+ * Iterating over an array in this fashion is 2.5x faster than iterating over a {@link HashSet}
+ * so it is worth copying the contents of the set to an array when iterating over it
+ * hundreds of times.
+ * @hide
+ */
+public final class FastImmutableArraySet<T> extends AbstractSet<T> {
+    FastIterator<T> mIterator;
+    T[] mContents;
+
+    public FastImmutableArraySet(T[] contents) {
+        mContents = contents;
+    }
+
+    @Override
+    public Iterator<T> iterator() {
+        FastIterator<T> it = mIterator;
+        if (it == null) {
+            it = new FastIterator<T>(mContents);
+            mIterator = it;
+        } else {
+            it.mIndex = 0;
+        }
+        return it;
+    }
+
+    @Override
+    public int size() {
+        return mContents.length;
+    }
+
+    private static final class FastIterator<T> implements Iterator<T> {
+        private final T[] mContents;
+        int mIndex;
+
+        public FastIterator(T[] contents) {
+            mContents = contents;
+        }
+
+        @Override
+        public boolean hasNext() {
+            return mIndex != mContents.length;
+        }
+
+        @Override
+        public T next() {
+            return mContents[mIndex++];
+        }
+
+        @Override
+        public void remove() {
+            throw new UnsupportedOperationException();
+        }
+    }
+}
diff --git a/services/java/com/android/server/IntentResolver.java b/services/java/com/android/server/IntentResolver.java
index a8b2840..e9ee12c 100644
--- a/services/java/com/android/server/IntentResolver.java
+++ b/services/java/com/android/server/IntentResolver.java
@@ -27,6 +27,8 @@
 import java.util.Map;
 import java.util.Set;
 
+import android.net.Uri;
+import android.util.FastImmutableArraySet;
 import android.util.Log;
 import android.util.PrintWriterPrinter;
 import android.util.Slog;
@@ -207,10 +209,11 @@
         final boolean debug = localLOGV ||
                 ((intent.getFlags() & Intent.FLAG_DEBUG_LOG_RESOLUTION) != 0);
 
+        FastImmutableArraySet<String> categories = getFastIntentCategories(intent);
         final String scheme = intent.getScheme();
         int N = listCut.size();
         for (int i = 0; i < N; ++i) {
-            buildResolveList(intent, debug, defaultOnly,
+            buildResolveList(intent, categories, debug, defaultOnly,
                              resolvedType, scheme, listCut.get(i), resultList);
         }
         sortResults(resultList);
@@ -286,20 +289,21 @@
             if (debug) Slog.v(TAG, "Action list: " + firstTypeCut);
         }
 
+        FastImmutableArraySet<String> categories = getFastIntentCategories(intent);
         if (firstTypeCut != null) {
-            buildResolveList(intent, debug, defaultOnly,
+            buildResolveList(intent, categories, debug, defaultOnly,
                     resolvedType, scheme, firstTypeCut, finalList);
         }
         if (secondTypeCut != null) {
-            buildResolveList(intent, debug, defaultOnly,
+            buildResolveList(intent, categories, debug, defaultOnly,
                     resolvedType, scheme, secondTypeCut, finalList);
         }
         if (thirdTypeCut != null) {
-            buildResolveList(intent, debug, defaultOnly,
+            buildResolveList(intent, categories, debug, defaultOnly,
                     resolvedType, scheme, thirdTypeCut, finalList);
         }
         if (schemeCut != null) {
-            buildResolveList(intent, debug, defaultOnly,
+            buildResolveList(intent, categories, debug, defaultOnly,
                     resolvedType, scheme, schemeCut, finalList);
         }
         sortResults(finalList);
@@ -478,9 +482,19 @@
         return false;
     }
 
-    private void buildResolveList(Intent intent, boolean debug, boolean defaultOnly,
+    private static FastImmutableArraySet<String> getFastIntentCategories(Intent intent) {
+        final Set<String> categories = intent.getCategories();
+        if (categories == null) {
+            return null;
+        }
+        return new FastImmutableArraySet<String>(categories.toArray(new String[categories.size()]));
+    }
+
+    private void buildResolveList(Intent intent, FastImmutableArraySet<String> categories,
+            boolean debug, boolean defaultOnly,
             String resolvedType, String scheme, List<F> src, List<R> dest) {
-        Set<String> categories = intent.getCategories();
+        final String action = intent.getAction();
+        final Uri data = intent.getData();
 
         final int N = src != null ? src.size() : 0;
         boolean hasNonDefaults = false;
@@ -498,8 +512,7 @@
                 continue;
             }
 
-            match = filter.match(
-                    intent.getAction(), resolvedType, scheme, intent.getData(), categories, TAG);
+            match = filter.match(action, resolvedType, scheme, data, categories, TAG);
             if (match >= 0) {
                 if (debug) Slog.v(TAG, "  Filter matched!  match=0x" +
                         Integer.toHexString(match));