1 files changed, 82 insertions, 1 deletions

diff --git a/third_party/sl4a/src/main/java/com/google/android/mobly/snippet/manager/SnippetManager.java b/third_party/sl4a/src/main/java/com/google/android/mobly/snippet/manager/SnippetManager.java
index ff0aec3..66e33b3 100644
--- a/third_party/sl4a/src/main/java/com/google/android/mobly/snippet/manager/SnippetManager.java
+++ b/third_party/sl4a/src/main/java/com/google/android/mobly/snippet/manager/SnippetManager.java
@@ -16,11 +16,17 @@
 
 package com.google.android.mobly.snippet.manager;
 
+import android.content.Context;
+import android.content.pm.ApplicationInfo;
+import android.content.pm.PackageManager;
 import android.os.Build;
+import android.os.Bundle;
 import com.google.android.mobly.snippet.Snippet;
+import com.google.android.mobly.snippet.event.EventSnippet;
 import com.google.android.mobly.snippet.rpc.MethodDescriptor;
 import com.google.android.mobly.snippet.rpc.RpcMinSdk;
 import com.google.android.mobly.snippet.rpc.RunOnUiThread;
+import com.google.android.mobly.snippet.schedulerpc.ScheduleRpcSnippet;
 import com.google.android.mobly.snippet.util.Log;
 import com.google.android.mobly.snippet.util.MainThread;
 import com.google.android.mobly.snippet.util.SnippetLibException;
@@ -30,18 +36,24 @@ import java.lang.reflect.Method;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.HashMap;
+import java.util.HashSet;
 import java.util.Map;
 import java.util.Map.Entry;
+import java.util.Set;
 import java.util.SortedSet;
 import java.util.TreeSet;
 import java.util.concurrent.Callable;
 
 public class SnippetManager {
+    private static final String METADATA_TAG_NAME = "mobly-snippets";
     private final Map<Class<? extends Snippet>, Snippet> mSnippets;
     /** A map of strings to known RPCs. */
     private final Map<String, MethodDescriptor> mKnownRpcs;
 
-    public SnippetManager(Collection<Class<? extends Snippet>> classList) {
+    private static SnippetManager sInstance = null;
+    private boolean mShutdown = false;
+
+    private SnippetManager(Collection<Class<? extends Snippet>> classList) {
         // Synchronized for multiple connections on the same session. Can't use ConcurrentHashMap
         // because we have to put in a value of 'null' before the class is constructed, but
         // ConcurrentHashMap does not allow null values.
@@ -65,6 +77,25 @@ public class SnippetManager {
         mKnownRpcs = Collections.unmodifiableMap(knownRpcs);
     }
 
+    public static synchronized SnippetManager initSnippetManager(Context context) {
+        if (sInstance != null) {
+            throw new IllegalStateException("SnippetManager should not be re-initialized");
+        }
+        Collection<Class<? extends Snippet>> classList = findSnippetClassesFromMetadata(context);
+        sInstance = new SnippetManager(classList);
+        return sInstance;
+    }
+
+    public static SnippetManager getInstance() {
+        if (sInstance == null) {
+            throw new IllegalStateException("getInstance() called before init()");
+        }
+        if (sInstance.isShutdown()) {
+            throw new IllegalStateException("shutdown() called before getInstance()");
+        }
+        return sInstance;
+    }
+
     public MethodDescriptor getMethodDescriptor(String methodName) {
         return mKnownRpcs.get(methodName);
     }
@@ -114,6 +145,56 @@ public class SnippetManager {
                 entry.getValue().shutdown();
             }
         }
+        mSnippets.clear();
+        mKnownRpcs.clear();
+        mShutdown = true;
+    }
+
+    public boolean isShutdown() {
+        return mShutdown;
+    }
+
+    private static Set<Class<? extends Snippet>> findSnippetClassesFromMetadata(Context context) {
+        ApplicationInfo appInfo;
+        try {
+            appInfo =
+                    context.getPackageManager()
+                            .getApplicationInfo(
+                                    context.getPackageName(), PackageManager.GET_META_DATA);
+        } catch (PackageManager.NameNotFoundException e) {
+            throw new IllegalStateException(
+                    "Failed to find ApplicationInfo with package name: "
+                            + context.getPackageName());
+        }
+        Bundle metadata = appInfo.metaData;
+        String snippets = metadata.getString(METADATA_TAG_NAME);
+        if (snippets == null) {
+            throw new IllegalStateException(
+                    "AndroidManifest.xml does not contain a <metadata> tag with "
+                            + "name=\""
+                            + METADATA_TAG_NAME
+                            + "\"");
+        }
+        String[] snippetClassNames = snippets.split("\\s*,\\s*");
+        Set<Class<? extends Snippet>> receiverSet = new HashSet<>();
+        /** Add the event snippet class which is provided within the Snippet Lib. */
+        receiverSet.add(EventSnippet.class);
+        /** Add the schedule RPC snippet class which is provided within the Snippet Lib. */
+        receiverSet.add(ScheduleRpcSnippet.class);
+        for (String snippetClassName : snippetClassNames) {
+            try {
+                Log.i("Trying to load Snippet class: " + snippetClassName);
+                Class<?> snippetClass = Class.forName(snippetClassName);
+                receiverSet.add((Class<? extends Snippet>) snippetClass);
+            } catch (ClassNotFoundException e) {
+                Log.e("Failed to find class " + snippetClassName);
+                throw new RuntimeException(e);
+            }
+        }
+        if (receiverSet.isEmpty()) {
+            throw new IllegalStateException("Found no subclasses of Snippet.");
+        }
+        return receiverSet;
     }
 
     private Snippet get(Class<? extends Snippet> clazz) throws Exception {