Parse layout/menu/drawable, etc XML files for R.id

To be used by a later CL where we use this more
complete picture of all the resource items to
generate our own R.java/class without invoking
AAPT (and split out AAPT to a separate action
that is off the java builder critical path).

Technically aapt creates R.id.foo for attr
<enum name="foo" ... /> and flag as well, but
I haven't seen code that actually relies on that.

Currently off-by-default (only exercised by tests).

--
MOS_MIGRATED_REVID=126407838

1 files changed, 85 insertions, 0 deletions

diff --git a/src/tools/android/java/com/google/devtools/build/android/DataValueFileWithIds.java b/src/tools/android/java/com/google/devtools/build/android/DataValueFileWithIds.java
new file mode 100644
index 0000000000..372e9dd989
--- /dev/null
+++ b/src/tools/android/java/com/google/devtools/build/android/DataValueFileWithIds.java
@@ -0,0 +1,85 @@
+// Copyright 2016 The Bazel Authors. All rights reserved.
+//
+// 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.google.devtools.build.android;
+
+import com.google.common.collect.ImmutableSet;
+import com.google.devtools.build.android.ParsedAndroidData.KeyValueConsumer;
+import com.google.devtools.build.android.xml.IdXmlResourceValue;
+
+import com.android.SdkConstants;
+import com.android.resources.ResourceType;
+
+import java.io.BufferedInputStream;
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.Iterator;
+
+import javax.xml.stream.XMLEventReader;
+import javax.xml.stream.XMLInputFactory;
+import javax.xml.stream.XMLStreamException;
+import javax.xml.stream.events.Attribute;
+import javax.xml.stream.events.StartElement;
+import javax.xml.stream.events.XMLEvent;
+
+/**
+ * Parses an XML file for "@+id/foo" and creates {@link IdXmlResourceValue} from parsed IDs.
+ * This can be a layout file, menu, drawable, etc.
+ */
+public class DataValueFileWithIds {
+
+  public static void parse(
+      XMLInputFactory xmlInputFactory,
+      Path source,
+      FullyQualifiedName fileKey,
+      FullyQualifiedName.Factory fqnFactory,
+      KeyValueConsumer<DataKey, DataResource> overwritingConsumer,
+      KeyValueConsumer<DataKey, DataResource> combiningConsumer)
+      throws IOException, XMLStreamException {
+    ImmutableSet.Builder<String> newIds = ImmutableSet.builder();
+    try (BufferedInputStream inStream = new BufferedInputStream(Files.newInputStream(source))) {
+      XMLEventReader eventReader =
+          xmlInputFactory.createXMLEventReader(inStream, StandardCharsets.UTF_8.toString());
+      // Go through every start tag and look at the values of all attributes (the attribute does
+      // not need to be android:id, e.g., android:layout_above="@+id/UpcomingView").
+      // If the any attribute's value begins with @+id/, then track it, since aapt seems to be
+      // forgiving and allow even non-android namespaced attributes to define a new ID.
+      while (eventReader.hasNext()) {
+        XMLEvent event = eventReader.nextEvent();
+        if (event.isStartElement()) {
+          StartElement start = event.asStartElement();
+          Iterator<Attribute> attributes = XmlResourceValues.iterateAttributesFrom(start);
+          while (attributes.hasNext()) {
+            Attribute attribute = attributes.next();
+            String value = attribute.getValue();
+            if (value.startsWith(SdkConstants.NEW_ID_PREFIX)) {
+              String idName = value.substring(SdkConstants.NEW_ID_PREFIX.length());
+              newIds.add(idName);
+            }
+          }
+        }
+      }
+      eventReader.close();
+    }
+    ImmutableSet<String> idResources = newIds.build();
+    overwritingConsumer.consume(fileKey, DataValueFile.of(source));
+    for (String id : idResources) {
+      combiningConsumer.consume(
+          fqnFactory.create(ResourceType.ID, id),
+          DataResourceXml.of(source, IdXmlResourceValue.of()));
+    }
+  }
+
+}