From 1901a5b4831537dcf673ecfb6ed256dd47e4f20f Mon Sep 17 00:00:00 2001
From: Robert Benea <robenea@google.com>
Date: Tue, 15 May 2018 16:36:07 -0700
Subject: [PATCH] Replace HashMap with ArrayMap for services

The number of services is pretty limited (100ish), use the more
memory efficient Map.

Test: tested on android go
Change-Id: I092c6816afba77fde4195c68a211804d4a561b77
---
 config/hiddenapi-light-greylist.txt              |  2 +-
 core/java/android/app/SystemServiceRegistry.java | 11 ++++++-----
 core/java/android/os/ServiceManager.java         |  4 ++--
 3 files changed, 9 insertions(+), 8 deletions(-)

diff --git a/config/hiddenapi-light-greylist.txt b/config/hiddenapi-light-greylist.txt
index b547baf7d7c83..1fcf8a5b57cba 100644
--- a/config/hiddenapi-light-greylist.txt
+++ b/config/hiddenapi-light-greylist.txt
@@ -1842,7 +1842,7 @@ Landroid/os/ServiceManager;->checkService(Ljava/lang/String;)Landroid/os/IBinder
 Landroid/os/ServiceManager;->getIServiceManager()Landroid/os/IServiceManager;
 Landroid/os/ServiceManager;->getService(Ljava/lang/String;)Landroid/os/IBinder;
 Landroid/os/ServiceManager;->listServices()[Ljava/lang/String;
-Landroid/os/ServiceManager;->sCache:Ljava/util/HashMap;
+Landroid/os/ServiceManager;->sCache:Ljava/util/Map;
 Landroid/os/ServiceManager;->sServiceManager:Landroid/os/IServiceManager;
 Landroid/os/ServiceManagerNative;->asInterface(Landroid/os/IBinder;)Landroid/os/IServiceManager;
 Landroid/os/SharedMemory;->getFd()I
diff --git a/core/java/android/app/SystemServiceRegistry.java b/core/java/android/app/SystemServiceRegistry.java
index db011dabac9e6..97d776d61c018 100644
--- a/core/java/android/app/SystemServiceRegistry.java
+++ b/core/java/android/app/SystemServiceRegistry.java
@@ -141,6 +141,7 @@ import android.telephony.SubscriptionManager;
 import android.telephony.TelephonyManager;
 import android.telephony.euicc.EuiccCardManager;
 import android.telephony.euicc.EuiccManager;
+import android.util.ArrayMap;
 import android.util.Log;
 import android.view.ContextThemeWrapper;
 import android.view.LayoutInflater;
@@ -162,7 +163,7 @@ import com.android.internal.net.INetworkWatchlistManager;
 import com.android.internal.os.IDropBoxManagerService;
 import com.android.internal.policy.PhoneLayoutInflater;
 
-import java.util.HashMap;
+import java.util.Map;
 
 /**
  * Manages all of the system services that can be returned by {@link Context#getSystemService}.
@@ -173,10 +174,10 @@ final class SystemServiceRegistry {
 
     // Service registry information.
     // This information is never changed once static initialization has completed.
-    private static final HashMap<Class<?>, String> SYSTEM_SERVICE_NAMES =
-            new HashMap<Class<?>, String>();
-    private static final HashMap<String, ServiceFetcher<?>> SYSTEM_SERVICE_FETCHERS =
-            new HashMap<String, ServiceFetcher<?>>();
+    private static final Map<Class<?>, String> SYSTEM_SERVICE_NAMES =
+            new ArrayMap<Class<?>, String>();
+    private static final Map<String, ServiceFetcher<?>> SYSTEM_SERVICE_FETCHERS =
+            new ArrayMap<String, ServiceFetcher<?>>();
     private static int sServiceCacheSize;
 
     // Not instantiable.
diff --git a/core/java/android/os/ServiceManager.java b/core/java/android/os/ServiceManager.java
index 165276d5c17e8..2966bff2ee4cb 100644
--- a/core/java/android/os/ServiceManager.java
+++ b/core/java/android/os/ServiceManager.java
@@ -16,13 +16,13 @@
 
 package android.os;
 
+import android.util.ArrayMap;
 import android.util.Log;
 
 import com.android.internal.annotations.GuardedBy;
 import com.android.internal.os.BinderInternal;
 import com.android.internal.util.StatLogger;
 
-import java.util.HashMap;
 import java.util.Map;
 
 /** @hide */
@@ -35,7 +35,7 @@ public final class ServiceManager {
     /**
      * Cache for the "well known" services, such as WM and AM.
      */
-    private static HashMap<String, IBinder> sCache = new HashMap<String, IBinder>();
+    private static Map<String, IBinder> sCache = new ArrayMap<String, IBinder>();
 
     /**
      * We do the "slow log" at most once every this interval.