PersistableBundle: writeToStream/readFromStream

Bug: 143911192
Test: manual sanity test
Change-Id: I208487d572c8148f28fac3307873dfdc90996ae1

2 files changed, 49 insertions, 0 deletions

diff --git a/api/current.txt b/api/current.txt
index a58c4f09efeb..6652df00c8a0 100644
--- a/api/current.txt
+++ b/api/current.txt
@@ -35220,7 +35220,9 @@ package android.os {
     method public int describeContents();
     method @Nullable public android.os.PersistableBundle getPersistableBundle(@Nullable String);
     method public void putPersistableBundle(@Nullable String, @Nullable android.os.PersistableBundle);
+    method @NonNull public static android.os.PersistableBundle readFromStream(@NonNull java.io.InputStream) throws java.io.IOException;
     method public void writeToParcel(android.os.Parcel, int);
+    method public void writeToStream(@NonNull java.io.OutputStream) throws java.io.IOException;
     field @NonNull public static final android.os.Parcelable.Creator<android.os.PersistableBundle> CREATOR;
     field public static final android.os.PersistableBundle EMPTY;
   }
diff --git a/core/java/android/os/PersistableBundle.java b/core/java/android/os/PersistableBundle.java
index 6f1bf71f187b..29aaf534eda1 100644
--- a/core/java/android/os/PersistableBundle.java
+++ b/core/java/android/os/PersistableBundle.java
@@ -16,17 +16,24 @@
 
 package android.os;
 
+import static java.nio.charset.StandardCharsets.UTF_8;
+
+import android.annotation.NonNull;
 import android.annotation.Nullable;
 import android.util.ArrayMap;
 import android.util.proto.ProtoOutputStream;
 
+import com.android.internal.util.FastXmlSerializer;
 import com.android.internal.util.XmlUtils;
 
 import org.xmlpull.v1.XmlPullParser;
 import org.xmlpull.v1.XmlPullParserException;
+import org.xmlpull.v1.XmlPullParserFactory;
 import org.xmlpull.v1.XmlSerializer;
 
 import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
 import java.util.ArrayList;
 
 /**
@@ -339,4 +346,44 @@ public final class PersistableBundle extends BaseBundle implements Cloneable, Pa
 
         proto.end(token);
     }
+
+    /**
+     * Writes the content of the {@link PersistableBundle} to a {@link OutputStream}.
+     *
+     * <p>The content can be read by a {@link #readFromStream}.
+     *
+     * @see #readFromStream
+     */
+    public void writeToStream(@NonNull OutputStream outputStream) throws IOException {
+        FastXmlSerializer serializer = new FastXmlSerializer();
+        serializer.setOutput(outputStream, UTF_8.name());
+        serializer.startTag(null, "bundle");
+        try {
+            saveToXml(serializer);
+        } catch (XmlPullParserException e) {
+            throw new IOException(e);
+        }
+        serializer.endTag(null, "bundle");
+        serializer.flush();
+    }
+
+    /**
+     * Reads a {@link PersistableBundle} from an {@link InputStream}.
+     *
+     * <p>The stream must be generated by {@link #writeToStream}.
+     *
+     * @see #writeToStream
+     */
+    @NonNull
+    public static PersistableBundle readFromStream(@NonNull InputStream inputStream)
+            throws IOException {
+        try {
+            XmlPullParser parser = XmlPullParserFactory.newInstance().newPullParser();
+            parser.setInput(inputStream, UTF_8.name());
+            parser.next();
+            return PersistableBundle.restoreFromXml(parser);
+        } catch (XmlPullParserException e) {
+            throw new IOException(e);
+        }
+    }
 }