ahat - An android heap dump viewer. Initial checkin.

ahat is an android-aware heap dump viewer based on perflib with a
simple html interface.

Change-Id: I7c18a7603dbbe735f778a95cd047f4f9ec1705ef
diff --git a/tools/ahat/src/RootsHandler.java b/tools/ahat/src/RootsHandler.java
new file mode 100644
index 0000000..185b9bf
--- /dev/null
+++ b/tools/ahat/src/RootsHandler.java
@@ -0,0 +1,51 @@
+/*
+ * Copyright (C) 2015 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 com.android.ahat;
+
+import com.android.tools.perflib.heap.Instance;
+import com.android.tools.perflib.heap.RootObj;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+
+class RootsHandler extends AhatHandler {
+  public RootsHandler(AhatSnapshot snapshot) {
+    super(snapshot);
+  }
+
+  @Override
+  public void handle(Doc doc, Query query) throws IOException {
+    doc.title("Roots");
+
+    Set<Instance> rootset = new HashSet<Instance>();
+    for (RootObj root : mSnapshot.getGCRoots()) {
+      Instance inst = root.getReferredInstance();
+      if (inst != null) {
+        rootset.add(inst);
+      }
+    }
+
+    List<Instance> roots = new ArrayList<Instance>();
+    for (Instance inst : rootset) {
+      roots.add(inst);
+    }
+    DominatedList.render(mSnapshot, doc, roots, query);
+  }
+}
+