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      1 /*
      2  * Copyright (C) 2016 The Android Open Source Project
      3  *
      4  * Licensed under the Apache License, Version 2.0 (the "License");
      5  * you may not use this file except in compliance with the License.
      6  * You may obtain a copy of the License at
      7  *
      8  *      http://www.apache.org/licenses/LICENSE-2.0
      9  *
     10  * Unless required by applicable law or agreed to in writing, software
     11  * distributed under the License is distributed on an "AS IS" BASIS,
     12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     13  * See the License for the specific language governing permissions and
     14  * limitations under the License.
     15  */
     16 
     17 package com.android.dialer.protos;
     18 
     19 import android.content.Intent;
     20 import android.os.Bundle;
     21 import android.support.annotation.NonNull;
     22 import com.android.dialer.common.Assert;
     23 import com.google.protobuf.InvalidProtocolBufferException;
     24 import com.google.protobuf.MessageLite;
     25 
     26 /** Useful methods for using Protocol Buffers with Android. */
     27 public final class ProtoParsers {
     28 
     29   private ProtoParsers() {}
     30 
     31   /** Retrieve a proto from a Bundle which was not created within the current executable/version. */
     32   @SuppressWarnings("unchecked") // We want to eventually optimize away parser classes, so cast
     33   public static <T extends MessageLite> T get(
     34       @NonNull Bundle bundle, @NonNull String key, @NonNull T defaultInstance)
     35       throws InvalidProtocolBufferException {
     36 
     37     Assert.isNotNull(bundle);
     38     Assert.isNotNull(key);
     39     Assert.isNotNull(defaultInstance);
     40 
     41     byte[] bytes = bundle.getByteArray(key);
     42     return (T) mergeFrom(bytes, defaultInstance.getDefaultInstanceForType());
     43   }
     44 
     45   /**
     46    * Retrieve a proto from a trusted bundle which was created within the current executable/version.
     47    *
     48    * @throws RuntimeException if the proto cannot be parsed
     49    */
     50   public static <T extends MessageLite> T getTrusted(
     51       @NonNull Bundle bundle, @NonNull String key, @NonNull T defaultInstance) {
     52     try {
     53       return get(bundle, key, defaultInstance);
     54     } catch (InvalidProtocolBufferException e) {
     55       throw Assert.createIllegalStateFailException(e.toString());
     56     }
     57   }
     58 
     59   /**
     60    * Retrieve a proto from a trusted bundle which was created within the current executable/version.
     61    *
     62    * @throws RuntimeException if the proto cannot be parsed
     63    */
     64   public static <T extends MessageLite> T getTrusted(
     65       @NonNull Intent intent, @NonNull String key, @NonNull T defaultInstance) {
     66     Assert.isNotNull(intent);
     67     return getTrusted(intent.getExtras(), key, defaultInstance);
     68   }
     69 
     70   /**
     71    * Stores a proto in a Bundle, for later retrieval by {@link #get(Bundle, String, MessageLite)} or
     72    * {@link #getFromInstanceState(Bundle, String, MessageLite)}.
     73    */
     74   public static void put(
     75       @NonNull Bundle bundle, @NonNull String key, @NonNull MessageLite message) {
     76     Assert.isNotNull(message);
     77     Assert.isNotNull(bundle);
     78     Assert.isNotNull(key);
     79     bundle.putByteArray(key, message.toByteArray());
     80   }
     81 
     82   /**
     83    * Stores a proto in an Intent, for later retrieval by {@link #get(Bundle, String, MessageLite)}.
     84    * Needs separate method because Intent has similar to but different API than Bundle.
     85    */
     86   public static void put(
     87       @NonNull Intent intent, @NonNull String key, @NonNull MessageLite message) {
     88     Assert.isNotNull(message);
     89     Assert.isNotNull(intent);
     90     Assert.isNotNull(key);
     91     intent.putExtra(key, message.toByteArray());
     92   }
     93 
     94   /** Parses a proto, throwing parser errors as runtime exceptions. */
     95   @SuppressWarnings("unchecked") // We want to eventually optimize away parser classes
     96   private static <T extends MessageLite> T mergeFrom(byte[] bytes, T defaultInstance) {
     97     try {
     98       return (T) defaultInstance.toBuilder().mergeFrom(bytes).build();
     99     } catch (InvalidProtocolBufferException e) {
    100       throw Assert.createIllegalStateFailException(e.toString());
    101     }
    102   }
    103 }
    104