android: Allow registering multiple CreationParams

content/public/android/java/src/org/chromium/content/browser/ChildProcessCreationParams.java

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 package org.chromium.content.browser;
 
 import android.content.Intent;
+import android.util.SparseArray;
 
 import org.chromium.base.library_loader.LibraryProcessType;
 
 /**
  * Allows specifying the package name for looking up child services
  * configuration and classes into (if it differs from the application
  * package name, like in the case of Android WebView). Also allows
  * specifying additional child service binging flags.
  */
 public class ChildProcessCreationParams {
+    private static final String EXTRA_LIBRARY_PROCESS_TYPE =
+            "org.chromium.content.common.child_service_params.library_process_type";
+
+    public static final int DEFAULT_ID = 0;
+    private static final Object sLock = new Object();
+    private static int sNextId = 1; // 0 is reserved for DEFAULT_ID.
+    private static final SparseArray<ChildProcessCreationParams> sParamMap = new SparseArray<>();
+
+    public static void registerDefault(ChildProcessCreationParams params) {

[Maria, 2017/02/24 05:32:42]

public methods should have javadoc here and below

[boliu, 2017/02/25 00:49:45]

Added one line javadoc to methods that are meant to be public.
getDefault() can be made package after webapk is fixed in next CL, so let a TODO
get() is made package

Also added an assert that default is never unregistered

+        synchronized (sLock) {
+            sParamMap.append(DEFAULT_ID, params);
+        }
+    }
+
+    public static ChildProcessCreationParams getDefault() {
+        return get(DEFAULT_ID);
+    }
+
+    public static int register(ChildProcessCreationParams params) {
+        assert params != null;
+        int id = -1;
+        synchronized (sLock) {
+            id = sNextId++;
+            sParamMap.append(id, params);
+        }
+        assert id > 0;
+        return id;
+    }
+
+    public static ChildProcessCreationParams get(int id) {
+        assert id >= 0;
+        synchronized (sLock) {
+            return sParamMap.get(id);
+        }
+    }
+
+    public static void unregister(int id) {
+        synchronized (sLock) {
+            sParamMap.delete(id);
+        }
+    }
+
+    // Members should all be immutable to avoid worrying about thread safety.
     private final String mPackageName;
     private final boolean mIsExternalService;
     private final int mLibraryProcessType;
-    private static final String EXTRA_LIBRARY_PROCESS_TYPE =
-            "org.chromium.content.common.child_service_params.library_process_type";
-
-    private static volatile ChildProcessCreationParams sChildProcessCreationParams;
-
-    public static void set(ChildProcessCreationParams params) {
-        sChildProcessCreationParams = params;
-    }
-
-    public static ChildProcessCreationParams get()  {
-        return sChildProcessCreationParams;
-    }
 
     public ChildProcessCreationParams(String packageName, boolean isExternalService,
             int libraryProcessType) {
         mPackageName = packageName;
         mIsExternalService = isExternalService;
         mLibraryProcessType = libraryProcessType;
     }
 
-    public ChildProcessCreationParams copy() {
-        return new ChildProcessCreationParams(mPackageName, mIsExternalService,
-                mLibraryProcessType);
-    }
-
-    public String getPackageName() {
+    String getPackageName() {
         return mPackageName;
     }
 
-    public boolean getIsExternalService() {
+    boolean getIsExternalService() {
         return mIsExternalService;
     }
 
-    public int getLibraryProcessType() {
+    int getLibraryProcessType() {
         return mLibraryProcessType;
     }
 
-    public void addIntentExtras(Intent intent) {
+    void addIntentExtras(Intent intent) {
         intent.putExtra(EXTRA_LIBRARY_PROCESS_TYPE, mLibraryProcessType);
     }
 
     public static int getLibraryProcessType(Intent intent) {
         return intent.getIntExtra(EXTRA_LIBRARY_PROCESS_TYPE,
                 LibraryProcessType.PROCESS_CHILD);
     }
 }