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 android.car.hardware;
18 
19 import static java.lang.Integer.toHexString;
20 
21 import android.annotation.SystemApi;
22 import android.os.Parcel;
23 import android.os.Parcelable;
24 
25 import java.nio.charset.Charset;
26 
27 /**
28  * Stores values broken down by area for a vehicle property.
29  *
30  * @param <T> refer to Parcel#writeValue(Object) to get a list of all supported types. The class
31  * should be visible to framework as default class loader is being used here.
32  *
33  * @hide
34  */
35 @SystemApi
36 public class CarPropertyValue<T> implements Parcelable {
37 
38     private final static Charset DEFAULT_CHARSET = Charset.forName("UTF-8");
39 
40     private final int mPropertyId;
41     private final int mAreaId;
42     private final T mValue;
43 
CarPropertyValue(int propertyId, T value)44     public CarPropertyValue(int propertyId, T value) {
45         this(propertyId, 0, value);
46     }
47 
CarPropertyValue(int propertyId, int areaId, T value)48     public CarPropertyValue(int propertyId, int areaId, T value) {
49         mPropertyId = propertyId;
50         mAreaId = areaId;
51         mValue = value;
52     }
53 
54     @SuppressWarnings("unchecked")
CarPropertyValue(Parcel in)55     public CarPropertyValue(Parcel in) {
56         mPropertyId = in.readInt();
57         mAreaId = in.readInt();
58         String valueClassName = in.readString();
59         Class<?> valueClass;
60         try {
61             valueClass = Class.forName(valueClassName);
62         } catch (ClassNotFoundException e) {
63             throw new IllegalArgumentException("Class not found: " + valueClassName);
64         }
65 
66         if (String.class.equals(valueClass)) {
67             byte[] bytes = in.readBlob();
68             mValue = (T) new String(bytes, DEFAULT_CHARSET);
69         } else if (byte[].class.equals(valueClass)) {
70             mValue = (T) in.readBlob();
71         } else {
72             mValue = (T) in.readValue(valueClass.getClassLoader());
73         }
74     }
75 
76     public static final Creator<CarPropertyValue> CREATOR = new Creator<CarPropertyValue>() {
77         @Override
78         public CarPropertyValue createFromParcel(Parcel in) {
79             return new CarPropertyValue(in);
80         }
81 
82         @Override
83         public CarPropertyValue[] newArray(int size) {
84             return new CarPropertyValue[size];
85         }
86     };
87 
88     @Override
describeContents()89     public int describeContents() {
90         return 0;
91     }
92 
93     @Override
writeToParcel(Parcel dest, int flags)94     public void writeToParcel(Parcel dest, int flags) {
95         dest.writeInt(mPropertyId);
96         dest.writeInt(mAreaId);
97 
98         Class<?> valueClass = mValue == null ? null : mValue.getClass();
99         dest.writeString(valueClass == null ? null : valueClass.getName());
100 
101         // Special handling for String and byte[] to mitigate transaction buffer limitations.
102         if (String.class.equals(valueClass)) {
103             dest.writeBlob(((String)mValue).getBytes(DEFAULT_CHARSET));
104         } else if (byte[].class.equals(valueClass)) {
105             dest.writeBlob((byte[]) mValue);
106         } else {
107             dest.writeValue(mValue);
108         }
109     }
110 
getPropertyId()111     public int getPropertyId() {
112         return mPropertyId;
113     }
114 
getAreaId()115     public int getAreaId() {
116         return mAreaId;
117     }
118 
getValue()119     public T getValue() {
120         return mValue;
121     }
122 
123     @Override
toString()124     public String toString() {
125         return "CarPropertyValue{" +
126                 "mPropertyId=0x" + toHexString(mPropertyId) +
127                 ", mAreaId=0x" + toHexString(mAreaId) +
128                 ", mValue=" + mValue +
129                 '}';
130     }
131 }
132