Import Android SDK Platform PI [4335822]

/google/data/ro/projects/android/fetch_artifact \
    --bid 4335822 \
    --target sdk_phone_armv7-win_sdk \
    sdk-repo-linux-sources-4335822.zip

AndroidVersion.ApiLevel has been modified to appear as 28

Change-Id: Ic8f04be005a71c2b9abeaac754d8da8d6f9a2c32

1 files changed, 201 insertions, 0 deletions

diff --git a/android/view/ViewHierarchyEncoder.java b/android/view/ViewHierarchyEncoder.java
new file mode 100644
index 00000000..87702161
--- /dev/null
+++ b/android/view/ViewHierarchyEncoder.java
@@ -0,0 +1,201 @@
+package android.view;
+
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+
+import java.io.ByteArrayOutputStream;
+import java.io.DataOutputStream;
+import java.io.IOException;
+import java.nio.charset.Charset;
+import java.util.HashMap;
+import java.util.Map;
+
+/**
+ * {@link ViewHierarchyEncoder} is a serializer that is tailored towards writing out
+ * view hierarchies (the view tree, along with the properties for each view) to a stream.
+ *
+ * It is typically used as follows:
+ * <pre>
+ *   ViewHierarchyEncoder e = new ViewHierarchyEncoder();
+ *
+ *   for (View view : views) {
+ *      e.beginObject(view);
+ *      e.addProperty("prop1", value);
+ *      ...
+ *      e.endObject();
+ *   }
+ *
+ *   // repeat above snippet for each view, finally end with:
+ *   e.endStream();
+ * </pre>
+ *
+ * <p>On the stream, a snippet such as the above gets encoded as a series of Map's (one
+ * corresponding to each view) with the property name as the key and the property value
+ * as the value.
+ *
+ * <p>Since the property names are practically the same across all views, rather than using
+ * the property name directly as the key, we use a short integer id corresponding to each
+ * property name as the key. A final map is added at the end which contains the mapping
+ * from the integer to its property name.
+ *
+ * <p>A value is encoded as a single byte type identifier followed by the encoding of the
+ * value. Only primitive types are supported as values, in addition to the Map type.
+ *
+ * @hide
+ */
+public class ViewHierarchyEncoder {
+    // Prefixes for simple primitives. These match the JNI definitions.
+    private static final byte SIG_BOOLEAN = 'Z';
+    private static final byte SIG_BYTE = 'B';
+    private static final byte SIG_SHORT = 'S';
+    private static final byte SIG_INT = 'I';
+    private static final byte SIG_LONG = 'J';
+    private static final byte SIG_FLOAT = 'F';
+    private static final byte SIG_DOUBLE = 'D';
+
+    // Prefixes for some commonly used objects
+    private static final byte SIG_STRING = 'R';
+
+    private static final byte SIG_MAP = 'M'; // a map with an short key
+    private static final short SIG_END_MAP = 0;
+
+    private final DataOutputStream mStream;
+
+    private final Map<String,Short> mPropertyNames = new HashMap<String, Short>(200);
+    private short mPropertyId = 1;
+    private Charset mCharset = Charset.forName("utf-8");
+
+    public ViewHierarchyEncoder(@NonNull ByteArrayOutputStream stream) {
+        mStream = new DataOutputStream(stream);
+    }
+
+    public void beginObject(@NonNull Object o) {
+        startPropertyMap();
+        addProperty("meta:__name__", o.getClass().getName());
+        addProperty("meta:__hash__", o.hashCode());
+    }
+
+    public void endObject() {
+        endPropertyMap();
+    }
+
+    public void endStream() {
+        // write out the string table
+        startPropertyMap();
+        addProperty("__name__", "propertyIndex");
+        for (Map.Entry<String,Short> entry : mPropertyNames.entrySet()) {
+            writeShort(entry.getValue());
+            writeString(entry.getKey());
+        }
+        endPropertyMap();
+    }
+
+    public void addProperty(@NonNull String name, boolean v) {
+        writeShort(createPropertyIndex(name));
+        writeBoolean(v);
+    }
+
+    public void addProperty(@NonNull String name, short s) {
+        writeShort(createPropertyIndex(name));
+        writeShort(s);
+    }
+
+    public void addProperty(@NonNull String name, int v) {
+        writeShort(createPropertyIndex(name));
+        writeInt(v);
+    }
+
+    public void addProperty(@NonNull String name, float v) {
+        writeShort(createPropertyIndex(name));
+        writeFloat(v);
+    }
+
+    public void addProperty(@NonNull String name, @Nullable String s) {
+        writeShort(createPropertyIndex(name));
+        writeString(s);
+    }
+
+    /**
+     * Writes the given name as the property name, and leaves it to the callee
+     * to fill in value for this property.
+     */
+    public void addPropertyKey(@NonNull String name) {
+        writeShort(createPropertyIndex(name));
+    }
+
+    private short createPropertyIndex(@NonNull String name) {
+        Short index = mPropertyNames.get(name);
+        if (index == null) {
+            index = mPropertyId++;
+            mPropertyNames.put(name, index);
+        }
+
+        return index;
+    }
+
+    private void startPropertyMap() {
+        try {
+            mStream.write(SIG_MAP);
+        } catch (IOException e) {
+            // does not happen since the stream simply wraps a ByteArrayOutputStream
+        }
+    }
+
+    private void endPropertyMap() {
+        writeShort(SIG_END_MAP);
+    }
+
+    private void writeBoolean(boolean v) {
+        try {
+            mStream.write(SIG_BOOLEAN);
+            mStream.write(v ? 1 : 0);
+        } catch (IOException e) {
+            // does not happen since the stream simply wraps a ByteArrayOutputStream
+        }
+    }
+
+    private void writeShort(short s) {
+        try {
+            mStream.write(SIG_SHORT);
+            mStream.writeShort(s);
+        } catch (IOException e) {
+            // does not happen since the stream simply wraps a ByteArrayOutputStream
+        }
+    }
+
+    private void writeInt(int i) {
+        try {
+            mStream.write(SIG_INT);
+            mStream.writeInt(i);
+        } catch (IOException e) {
+            // does not happen since the stream simply wraps a ByteArrayOutputStream
+        }
+    }
+
+    private void writeFloat(float v) {
+        try {
+            mStream.write(SIG_FLOAT);
+            mStream.writeFloat(v);
+        } catch (IOException e) {
+            // does not happen since the stream simply wraps a ByteArrayOutputStream
+        }
+    }
+
+    private void writeString(@Nullable String s) {
+        if (s == null) {
+            s = "";
+        }
+
+        try {
+            mStream.write(SIG_STRING);
+            byte[] bytes = s.getBytes(mCharset);
+
+            short len = (short)Math.min(bytes.length, Short.MAX_VALUE);
+            mStream.writeShort(len);
+
+            mStream.write(bytes, 0, len);
+        } catch (IOException e) {
+            // does not happen since the stream simply wraps a ByteArrayOutputStream
+        }
+    }
+}