Allow passing in a custom native library loader.

All previous initialize methods are deprecated and a new initialize
that uses a builder pattern is added. This gives us full control over
the order of initialization.

Bug: webrtc:7474
Change-Id: I006190e50f2e75c5015f0be75b86d367676db2cc
Reviewed-on: https://webrtc-review.googlesource.com/4160
Reviewed-by: Magnus Jedvert <magjed@webrtc.org>
Commit-Queue: Sami Kalliomäki <sakal@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#20037}

sdk/android/api/org/webrtc/PeerConnectionFactory.java

@@ -18,15 +18,10 @@ import java.util.List;
  * the PeerConnection API for clients.
  */
 public class PeerConnectionFactory {
-  private static volatile boolean nativeLibLoaded;
-
   static {
-    try {
-      System.loadLibrary("jingle_peerconnection_so");
-      nativeLibLoaded = true;
-    } catch (UnsatisfiedLinkError t) {
-      nativeLibLoaded = false;
-    }
+    // TODO(sakal): Remove once all dependencies have started using
+    // PeerConnectionFactory.initialize.
+    NativeLibrary.initialize(new NativeLibrary.DefaultLoader());
   }
 
   public static final String TRIAL_ENABLED = "Enabled";
@@ -42,6 +37,65 @@ public class PeerConnectionFactory {
   private EglBase localEglbase;
   private EglBase remoteEglbase;
 
+  public static class InitializationOptions {
+    final Context applicationContext;
+    final String fieldTrials;
+    final boolean enableInternalTracer;
+    final boolean enableVideoHwAcceleration;
+    final NativeLibraryLoader nativeLibraryLoader;
+
+    private InitializationOptions(Context applicationContext, String fieldTrials,
+        boolean enableInternalTracer, boolean enableVideoHwAcceleration,
+        NativeLibraryLoader nativeLibraryLoader) {
+      this.applicationContext = applicationContext;
+      this.fieldTrials = fieldTrials;
+      this.enableInternalTracer = enableInternalTracer;
+      this.enableVideoHwAcceleration = enableVideoHwAcceleration;
+      this.nativeLibraryLoader = nativeLibraryLoader;
+    }
+
+    public static Builder builder(Context applicationContext) {
+      return new Builder(applicationContext);
+    }
+
+    public static class Builder {
+      private final Context applicationContext;
+      private String fieldTrials = "";
+      private boolean enableInternalTracer = true;
+      private boolean enableVideoHwAcceleration = true;
+      private NativeLibraryLoader nativeLibraryLoader = new NativeLibrary.DefaultLoader();
+
+      Builder(Context applicationContext) {
+        this.applicationContext = applicationContext;
+      }
+
+      public Builder setFieldTrials(String fieldTrials) {
+        this.fieldTrials = fieldTrials;
+        return this;
+      }
+
+      public Builder setEnableInternalTracer(boolean enableInternalTracer) {
+        this.enableInternalTracer = enableInternalTracer;
+        return this;
+      }
+
+      public Builder setEnableVideoHwAcceleration(boolean enableVideoHwAcceleration) {
+        this.enableVideoHwAcceleration = enableVideoHwAcceleration;
+        return this;
+      }
+
+      public Builder setNativeLibraryLoader(NativeLibraryLoader nativeLibraryLoader) {
+        this.nativeLibraryLoader = nativeLibraryLoader;
+        return this;
+      }
+
+      public PeerConnectionFactory.InitializationOptions createInitializationOptions() {
+        return new PeerConnectionFactory.InitializationOptions(applicationContext, fieldTrials,
+            enableInternalTracer, enableVideoHwAcceleration, nativeLibraryLoader);
+      }
+    }
+  }
+
   public static class Options {
     // Keep in sync with webrtc/rtc_base/network.h!
     static final int ADAPTER_TYPE_UNKNOWN = 0;
@@ -56,17 +110,35 @@ public class PeerConnectionFactory {
     public boolean disableNetworkMonitor;
   }
 
+  /**
+   * Loads and initializes WebRTC. This must be called at least once before creating a
+   * PeerConnectionFactory. Replaces all the old initialization methods. Must not be called while
+   * a PeerConnectionFactory is alive.
+   */
+  public static void initialize(InitializationOptions options) {
+    ContextUtils.initialize(options.applicationContext);
+    NativeLibrary.initialize(options.nativeLibraryLoader);
+    nativeInitializeAndroidGlobals(options.applicationContext, options.enableVideoHwAcceleration);
+    initializeFieldTrials(options.fieldTrials);
+    if (options.enableInternalTracer) {
+      initializeInternalTracer();
+    }
+  }
+
   // Must be called at least once before creating a PeerConnectionFactory
   // (for example, at application startup time).
-  public static native void nativeInitializeAndroidGlobals(
+  private static native void nativeInitializeAndroidGlobals(
       Context context, boolean videoHwAcceleration);
 
+  // Deprecated, use PeerConnectionFactory.initialize instead.
+  @Deprecated
   public static void initializeAndroidGlobals(Context context, boolean videoHwAcceleration) {
     ContextUtils.initialize(context);
     nativeInitializeAndroidGlobals(context, videoHwAcceleration);
   }
 
   // Older signature of initializeAndroidGlobals. The extra parameters are now meaningless.
+  // Deprecated, use PeerConnectionFactory.initialize instead.
   @Deprecated
   public static boolean initializeAndroidGlobals(Object context, boolean initializeAudio,
       boolean initializeVideo, boolean videoHwAcceleration) {
@@ -76,7 +148,8 @@ public class PeerConnectionFactory {
 
   // Field trial initialization. Must be called before PeerConnectionFactory
   // is created.
-  public static native void initializeFieldTrials(String fieldTrialsInitString);
+  // Deprecated, use PeerConnectionFactory.initialize instead.
+  @Deprecated public static native void initializeFieldTrials(String fieldTrialsInitString);
   // Wrapper of webrtc::field_trial::FindFullName. Develop the feature with default behaviour off.
   // Example usage:
   // if (PeerConnectionFactory.fieldTrialsFindFullName("WebRTCExperiment").equals("Enabled")) {
@@ -85,12 +158,13 @@ public class PeerConnectionFactory {
   //   method2();
   // }
   public static String fieldTrialsFindFullName(String name) {
-    return nativeLibLoaded ? nativeFieldTrialsFindFullName(name) : "";
+    return NativeLibrary.isLoaded() ? nativeFieldTrialsFindFullName(name) : "";
   }
   private static native String nativeFieldTrialsFindFullName(String name);
   // Internal tracing initialization. Must be called before PeerConnectionFactory is created to
   // prevent racing with tracing code.
-  public static native void initializeInternalTracer();
+  // Deprecated, use PeerConnectionFactory.initialize instead.
+  @Deprecated public static native void initializeInternalTracer();
   // Internal tracing shutdown, called to prevent resource leaks. Must be called after
   // PeerConnectionFactory is gone to prevent races with code performing tracing.
   public static native void shutdownInternalTracer();
@@ -111,6 +185,11 @@ public class PeerConnectionFactory {
 
   public PeerConnectionFactory(
       Options options, VideoEncoderFactory encoderFactory, VideoDecoderFactory decoderFactory) {
+    if (!NativeLibrary.isLoaded() || ContextUtils.getApplicationContext() == null) {
+      throw new IllegalStateException(
+          "PeerConnectionFactory.initialize was not called before creating a "
+          + "PeerConnectionFactory.");
+    }
     nativeFactory = nativeCreatePeerConnectionFactory(options, encoderFactory, decoderFactory);
     if (nativeFactory == 0) {
       throw new RuntimeException("Failed to initialize PeerConnectionFactory!");