Create a ParsedNdefMessage class with supporting implementations.

Change-Id: I13a199ad01a726a30e8851a675386c34f2dfa605

apps/Tag/src/com/android/apps/tag/NdefUtil.java

@@ -16,20 +16,12 @@
 
 package com.android.apps.tag;
 
-import com.android.apps.tag.record.ParsedNdefRecord;
-import com.android.apps.tag.record.SmartPoster;
-import com.android.apps.tag.record.TextRecord;
-import com.android.apps.tag.record.UriRecord;
-import com.google.common.collect.Iterables;
-import com.google.common.primitives.Bytes;
-
 import android.net.Uri;
-import android.nfc.NdefMessage;
 import android.nfc.NdefRecord;
 
+import com.google.common.primitives.Bytes;
+
 import java.nio.charset.Charsets;
-import java.util.ArrayList;
-import java.util.List;
 
 /**
  * Utilities for dealing with conversions to and from NdefRecords.
@@ -60,34 +52,4 @@ public class NdefUtil {
         return new NdefRecord(NdefRecord.TNF_WELL_KNOWN,
                 NdefRecord.RTD_URI, EMPTY, payload);
     }
-
-    public static Iterable<TextRecord> getTextFields(NdefMessage message) {
-        return Iterables.filter(getObjects(message), TextRecord.class);
-    }
-
-    public static Iterable<UriRecord> getUris(NdefMessage message) {
-        return Iterables.filter(getObjects(message), UriRecord.class);
-    }
-
-    /**
-     * Parse the provided {@code NdefMessage}, extracting all known
-     * objects from the message.  Typically this list will consist of
-     * {@link String}s corresponding to NDEF text records, or {@link Uri}s
-     * corresponding to NDEF URI records.
-     * <p>
-     * TODO: Is this API too generic?  Should we keep it?
-     */
-    public static Iterable<ParsedNdefRecord> getObjects(NdefMessage message) {
-        List<ParsedNdefRecord> retval = new ArrayList<ParsedNdefRecord>();
-        for (NdefRecord record : message.getRecords()) {
-            if (UriRecord.isUri(record)) {
-                retval.add(UriRecord.parse(record));
-            } else if (TextRecord.isText(record)) {
-                retval.add(TextRecord.parse(record));
-            } else if (SmartPoster.isPoster(record)) {
-                retval.add(SmartPoster.parse(record));
-            }
-        }
-        return retval;
-    }
 }

apps/Tag/src/com/android/apps/tag/TagAdapter.java

@@ -16,14 +16,10 @@
 
 package com.android.apps.tag;
 
-import com.android.apps.tag.TagDBHelper.NdefMessagesTable;
-
 import android.content.Context;
 import android.database.Cursor;
-import android.net.Uri;
 import android.nfc.FormatException;
 import android.nfc.NdefMessage;
-import android.nfc.NdefRecord;
 import android.text.format.DateUtils;
 import android.util.Log;
 import android.view.LayoutInflater;
@@ -32,9 +28,12 @@ import android.view.ViewGroup;
 import android.widget.Adapter;
 import android.widget.CursorAdapter;
 import android.widget.TextView;
-import com.android.apps.tag.record.SmartPoster;
+
-import com.android.apps.tag.record.TextRecord;
+import com.android.apps.tag.TagDBHelper.NdefMessagesTable;
-import com.android.apps.tag.record.UriRecord;
+import com.android.apps.tag.message.NdefMessageParser;
+import com.android.apps.tag.message.ParsedNdefMessage;
+
+import java.util.Locale;
 
 /**
  * A custom {@link Adapter} that renders tag entries for a list.
@@ -63,23 +62,8 @@ public class TagAdapter extends CursorAdapter {
         if (msg == null) {
             mainLine.setText("Invalid tag");
         } else {
-            try {
+            ParsedNdefMessage parsedMsg = NdefMessageParser.parse(msg);
-                SmartPoster poster = SmartPoster.parse(msg.getRecords()[0]);
+            mainLine.setText(parsedMsg.getSnippet(Locale.getDefault()));
-                TextRecord title = poster.getTitle();
-                if (title != null) {
-                    mainLine.setText(title.getText());
-                }
-            } catch (IllegalArgumentException e) {
-                // Not a smart poster
-                NdefRecord record = msg.getRecords()[0];
-                Uri uri = null;
-                try {
-                    uri = UriRecord.parse(record).getUri();
-                    mainLine.setText(uri.toString());
-                } catch (IllegalArgumentException e2) {
-                    mainLine.setText("Not a smart poster or URL");
-                }
-            }
         }
         dateLine.setText(DateUtils.getRelativeTimeSpanString(
                 context, cursor.getLong(cursor.getColumnIndex(NdefMessagesTable.DATE))));

apps/Tag/src/com/android/apps/tag/TagDBHelper.java

@@ -16,8 +16,6 @@
 
 package com.android.apps.tag;
 
-import com.google.common.annotations.VisibleForTesting;
-
 import android.content.Context;
 import android.database.sqlite.SQLiteDatabase;
 import android.database.sqlite.SQLiteOpenHelper;
@@ -27,6 +25,8 @@ import android.nfc.FormatException;
 import android.nfc.NdefMessage;
 import android.nfc.NdefRecord;
 
+import com.google.common.annotations.VisibleForTesting;
+
 /**
  * Database utilities for the saved tags.
  */

apps/Tag/src/com/android/apps/tag/TagList.java

@@ -16,8 +16,6 @@
 
 package com.android.apps.tag;
 
-import com.android.apps.tag.TagDBHelper.NdefMessagesTable;
-
 import android.app.Activity;
 import android.app.AlertDialog;
 import android.app.Dialog;
@@ -35,6 +33,8 @@ import android.view.Menu;
 import android.view.View;
 import android.widget.ListView;
 
+import com.android.apps.tag.TagDBHelper.NdefMessagesTable;
+
 /**
  * An {@link Activity} that displays a flat list of tags that can be "opened".
  */

apps/Tag/src/com/android/apps/tag/TagViewer.java

@@ -30,10 +30,11 @@ import android.view.LayoutInflater;
 import android.view.WindowManager;
 import android.widget.LinearLayout;
 import android.widget.TextView;
-import com.android.apps.tag.record.ParsedNdefRecord;
+
-import com.android.apps.tag.record.SmartPoster;
+import com.android.apps.tag.message.NdefMessageParser;
-import com.android.apps.tag.record.TextRecord;
+import com.android.apps.tag.message.ParsedNdefMessage;
-import com.android.apps.tag.record.UriRecord;
+
+import java.util.Locale;
 
 /**
  * An {@link Activity} which handles a broadcast of a new tag that the device just discovered.
@@ -93,35 +94,11 @@ public class TagViewer extends Activity {
         // The body of the dialog should use the light theme
 
         // Build the views from the logical records in the messages
-        boolean first = true;
         for (NdefMessage msg : msgs) {
-            Iterable<ParsedNdefRecord> objects = NdefUtil.getObjects(msg);
+            ParsedNdefMessage parsedMsg = NdefMessageParser.parse(msg);
-            for (ParsedNdefRecord object : objects) {
+            TextView text = (TextView) inflater.inflate(R.layout.tag_text, list, false);
-                if (!first) {
+            text.setText(parsedMsg.getSnippet(Locale.getDefault()));
-                    list.addView(inflater.inflate(R.layout.tag_divider, list, false));
+            list.addView(text);
-                    first = false;
-                }
-
-                if (object instanceof TextRecord) {
-                    TextRecord textRecord = (TextRecord) object;
-                    TextView text = (TextView) inflater.inflate(R.layout.tag_text, list, false);
-                    text.setText(textRecord.getText());
-                    list.addView(text);
-                } else if (object instanceof UriRecord) {
-                    UriRecord uriRecord = (UriRecord) object;
-                    TextView text = (TextView) inflater.inflate(R.layout.tag_text, list, false);
-                    text.setText(uriRecord.getUri().toString());
-                    list.addView(text);
-                } else if (object instanceof SmartPoster) {
-                    TextView text = (TextView) inflater.inflate(R.layout.tag_text, list, false);
-                    SmartPoster poster = (SmartPoster) object;
-                    TextRecord title = poster.getTitle();
-                    if (title != null) {
-                        text.setText(title.getText());
-                    }
-                    list.addView(text);
-                }
-            }
         }
     }
     

apps/Tag/src/com/android/apps/tag/message/EmptyMessage.java

@@ -0,0 +1,37 @@
+/*
+ * Copyright (C) 2010 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.apps.tag.message;
+
+import java.util.Locale;
+
+/**
+ * A parsed message containing no elements.
+ */
+class EmptyMessage implements ParsedNdefMessage {
+
+    /* package private */ EmptyMessage() { }
+
+    @Override
+    public String getSnippet(Locale locale) {
+        return "Empty Tag";  // TODO: localize
+    }
+
+    @Override
+    public boolean isStarred() {
+        return false;
+    }
+}

apps/Tag/src/com/android/apps/tag/message/NdefMessageParser.java

@@ -0,0 +1,76 @@
+/*
+ * Copyright (C) 2010 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.apps.tag.message;
+
+import android.nfc.NdefMessage;
+import android.nfc.NdefRecord;
+
+import com.android.apps.tag.record.ParsedNdefRecord;
+import com.android.apps.tag.record.SmartPoster;
+import com.android.apps.tag.record.TextRecord;
+import com.android.apps.tag.record.UriRecord;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * Utility class for creating {@link ParsedNdefMessage}s.
+ */
+public class NdefMessageParser {
+
+    // Utility class
+    private NdefMessageParser() { }
+
+    /** Parse an NdefMessage */
+    public static ParsedNdefMessage parse(NdefMessage message) {
+        List<ParsedNdefRecord> elements = getRecords(message);
+
+        if (elements.isEmpty()) {
+            return new EmptyMessage();
+        }
+
+        ParsedNdefRecord first = elements.get(0);
+
+        if (elements.size() == 1) {
+            if (first instanceof SmartPoster) {
+                return new SmartPosterMessage((SmartPoster) first);
+            }
+            if (first instanceof TextRecord) {
+                return new TextMessage((TextRecord) first);
+            }
+            if (first instanceof UriRecord) {
+                return new UriMessage((UriRecord) first);
+            }
+        }
+
+        return new UnknownMessage(elements);
+    }
+
+    public static List<ParsedNdefRecord> getRecords(NdefMessage message) {
+        List<ParsedNdefRecord> elements = new ArrayList<ParsedNdefRecord>();
+        for (NdefRecord record : message.getRecords()) {
+            if (UriRecord.isUri(record)) {
+                elements.add(UriRecord.parse(record));
+            } else if (TextRecord.isText(record)) {
+                elements.add(TextRecord.parse(record));
+            } else if (SmartPoster.isPoster(record)) {
+                elements.add(SmartPoster.parse(record));
+            }
+        }
+        return elements;
+    }
+}

apps/Tag/src/com/android/apps/tag/message/ParsedNdefMessage.java

@@ -0,0 +1,35 @@
+/*
+ * Copyright (C) 2010 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.apps.tag.message;
+
+import java.util.Locale;
+
+/**
+ * A parsed version of an {@link android.nfc.NdefMessage}
+ */
+public interface ParsedNdefMessage {
+
+    /**
+     * Returns the snippet information associated with the NdefMessage
+     * most appropriate for the given {@code locale}.
+     */
+    public String getSnippet(Locale locale);
+
+    // TODO: Determine if this is the best place for holding whether
+    // the user has starred this parsed message.
+    public boolean isStarred();
+}

apps/Tag/src/com/android/apps/tag/message/SmartPosterMessage.java

@@ -0,0 +1,48 @@
+/*
+ * Copyright (C) 2010 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.apps.tag.message;
+
+import com.android.apps.tag.record.SmartPoster;
+import com.android.apps.tag.record.TextRecord;
+import com.google.common.base.Preconditions;
+
+import java.util.Locale;
+
+/**
+ * A message consisting of one {@link SmartPoster} object.
+ */
+class SmartPosterMessage implements ParsedNdefMessage {
+    private final SmartPoster mPoster;
+
+    SmartPosterMessage(SmartPoster poster) {
+        mPoster = Preconditions.checkNotNull(poster);
+    }
+
+    @Override
+    public String getSnippet(Locale locale) {
+        TextRecord title = mPoster.getTitle();
+        if (title == null) {
+            return mPoster.getUriRecord().getUri().toString();
+        }
+        return title.getText();
+    }
+
+    @Override
+    public boolean isStarred() {
+        return false;
+    }
+}

apps/Tag/src/com/android/apps/tag/message/TextMessage.java

@@ -0,0 +1,43 @@
+/*
+ * Copyright (C) 2010 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.apps.tag.message;
+
+import com.android.apps.tag.record.TextRecord;
+import com.google.common.base.Preconditions;
+
+import java.util.Locale;
+
+/**
+ * A message containing one text element
+ */
+class TextMessage implements ParsedNdefMessage {
+    private final TextRecord mRecord;
+
+    TextMessage(TextRecord record) {
+        mRecord = Preconditions.checkNotNull(record);
+    }
+
+    @Override
+    public String getSnippet(Locale locale) {
+        return mRecord.getText();
+    }
+
+    @Override
+    public boolean isStarred() {
+        return false;
+    }
+}

apps/Tag/src/com/android/apps/tag/message/UnknownMessage.java

@@ -0,0 +1,45 @@
+/*
+ * Copyright (C) 2010 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.apps.tag.message;
+
+import com.android.apps.tag.record.ParsedNdefRecord;
+import com.google.common.collect.ImmutableList;
+
+import java.util.Locale;
+
+/**
+ * The catchall parsed message format for when nothing else better applies.
+ */
+class UnknownMessage implements ParsedNdefMessage {
+
+    private final ImmutableList<ParsedNdefRecord> mRecords;
+
+    UnknownMessage(Iterable<ParsedNdefRecord> records) {
+        mRecords = ImmutableList.copyOf(records);
+    }
+
+    @Override
+    public String getSnippet(Locale locale) {
+        // TODO: localize
+        return "Unknown record type with " + mRecords.size() + " elements.";
+    }
+
+    @Override
+    public boolean isStarred() {
+        return false;
+    }
+}

apps/Tag/src/com/android/apps/tag/message/UriMessage.java

@@ -0,0 +1,45 @@
+/*
+ * Copyright (C) 2010 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.apps.tag.message;
+
+import com.android.apps.tag.record.UriRecord;
+import com.google.common.base.Preconditions;
+
+import java.util.Locale;
+
+/**
+ * A {@link ParsedNdefMessage} consisting of one {@link UriRecord}.
+ */
+class UriMessage implements ParsedNdefMessage {
+
+    private final UriRecord mRecord;
+
+    UriMessage(UriRecord record) {
+        mRecord = Preconditions.checkNotNull(record);
+    }
+
+    @Override
+    public String getSnippet(Locale locale) {
+        // URIs cannot be localized
+        return mRecord.getUri().toString();
+    }
+
+    @Override
+    public boolean isStarred() {
+        return false;
+    }
+}

apps/Tag/src/com/android/apps/tag/record/SmartPoster.java

@@ -16,16 +16,16 @@
 
 package com.android.apps.tag.record;
 
-import com.android.apps.tag.NdefUtil;
-import com.google.common.base.Preconditions;
-import com.google.common.collect.Iterables;
-
 import android.nfc.FormatException;
 import android.nfc.NdefMessage;
 import android.nfc.NdefRecord;
 
-import java.util.Arrays;
+import com.android.apps.tag.message.NdefMessageParser;
+import com.google.common.base.Preconditions;
+import com.google.common.collect.Iterables;
 
+import java.util.Arrays;
+import java.util.NoSuchElementException;
 import javax.annotation.Nullable;
 
 /**
@@ -73,8 +73,12 @@ public class SmartPoster implements ParsedNdefRecord {
         Preconditions.checkArgument(Arrays.equals(record.getType(), NdefRecord.RTD_SMART_POSTER));
         try {
             NdefMessage subRecords = new NdefMessage(record.getPayload());
-            UriRecord uri = Iterables.getOnlyElement(NdefUtil.getUris(subRecords));
+
-            Iterable<TextRecord> textFields = NdefUtil.getTextFields(subRecords);
+            Iterable<ParsedNdefRecord> records = NdefMessageParser.getRecords(subRecords);
+
+            UriRecord uri = Iterables.getOnlyElement(Iterables.filter(records, UriRecord.class));
+            Iterable<TextRecord> textFields = Iterables.filter(records, TextRecord.class);
+
             TextRecord title = null;
             if (!Iterables.isEmpty(textFields)) {
                 title = Iterables.get(textFields, 0);
@@ -83,6 +87,8 @@ public class SmartPoster implements ParsedNdefRecord {
             return new SmartPoster(uri, title);
         } catch (FormatException e) {
             throw new IllegalArgumentException(e);
+        } catch (NoSuchElementException e) {
+            throw new IllegalArgumentException(e);
         }
     }
 

apps/Tag/src/com/android/apps/tag/record/TextRecord.java

@@ -17,6 +17,7 @@
 package com.android.apps.tag.record;
 
 import android.nfc.NdefRecord;
+
 import com.google.common.base.Preconditions;
 
 import java.io.UnsupportedEncodingException;
@@ -27,6 +28,7 @@ import java.util.Arrays;
  */
 public class TextRecord implements ParsedNdefRecord {
 
+    /** ISO/IANA language code */
     private final String mLanguageCode;
     private final String mText;
 
@@ -44,6 +46,11 @@ public class TextRecord implements ParsedNdefRecord {
         return mText;
     }
 
+    /**
+     * Returns the ISO/IANA language code associated with this text element.
+     *
+     * TODO: this should return a {@link java.util.Locale}
+     */
     public String getLanguageCode() {
         return mLanguageCode;
     }

apps/Tag/src/com/android/apps/tag/record/UriRecord.java

@@ -18,6 +18,7 @@ package com.android.apps.tag.record;
 
 import android.net.Uri;
 import android.nfc.NdefRecord;
+
 import com.google.common.base.Preconditions;
 import com.google.common.collect.BiMap;
 import com.google.common.collect.ImmutableBiMap;

apps/Tag/tests/src/com/android/apps/tag/NdefUtilTest.java

@@ -16,10 +16,11 @@
 
 package com.android.apps.tag;
 
+import android.nfc.NdefRecord;
 import android.test.AndroidTestCase;
+
 import com.android.apps.tag.record.TextRecord;
 import com.google.common.primitives.Bytes;
-import android.nfc.NdefRecord;
 
 import java.io.UnsupportedEncodingException;
 

apps/Tag/tests/src/com/android/apps/tag/SmartPosterTest.java

@@ -16,8 +16,9 @@
 
 package com.android.apps.tag;
 
-import android.test.AndroidTestCase;
 import android.nfc.NdefMessage;
+import android.test.AndroidTestCase;
+
 import com.android.apps.tag.record.SmartPoster;
 
 /**