• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * Copyright (C) 2019 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.car.telephony.common;
18 
19 import android.net.Uri;
20 
21 import androidx.annotation.NonNull;
22 import androidx.annotation.Nullable;
23 
24 import java.util.ArrayList;
25 import java.util.HashSet;
26 import java.util.List;
27 import java.util.Set;
28 import java.util.stream.Collectors;
29 
30 /** Represents query parameters. */
31 public class QueryParam {
32 
33     /** Creates a provider always returning the same query param instance. */
of(final QueryParam queryParam)34     public static Provider of(final QueryParam queryParam) {
35         return () -> queryParam;
36     }
37 
38     /**
39      * An object capable of providing instances of {@link QueryParam}. It can be used in two
40      * circumstances:
41      * <ul>
42      * <li>Return the same instance every time calling the getter.
43      * <li>Return an updated instance or create a new instance every time calling the getter.
44      *
45      * @deprecated use {@link QueryBuilder}.
46      */
47     @Deprecated
48     public interface Provider {
49 
50         /** Returns an instance of query params. */
51         @Nullable
getQueryParam()52         QueryParam getQueryParam();
53     }
54 
55     /** Used by {@link ObservableAsyncQuery#startQuery()} as query param. */
56     final Uri mUri;
57     /** Used by {@link ObservableAsyncQuery#startQuery()} as query param. */
58     final String[] mProjection;
59     /** Used by {@link ObservableAsyncQuery#startQuery()} as query param. */
60     final String mSelection;
61     /** Used by {@link ObservableAsyncQuery#startQuery()} as query param. */
62     final String[] mSelectionArgs;
63     /** Used by {@link ObservableAsyncQuery#startQuery()} as query param. */
64     final String mOrderBy;
65     /** Used by {@link ObservableAsyncQuery#startQuery()} to check query permission. */
66     final String mPermission;
67 
QueryParam( @onNull Uri uri, @Nullable String[] projection, @Nullable String selection, @Nullable String[] selectionArgs, @Nullable String orderBy, @NonNull String permission)68     public QueryParam(
69             @NonNull Uri uri,
70             @Nullable String[] projection,
71             @Nullable String selection,
72             @Nullable String[] selectionArgs,
73             @Nullable String orderBy,
74             @NonNull String permission) {
75         mUri = uri;
76         mProjection = projection;
77         mSelection = selection;
78         mSelectionArgs = selectionArgs;
79         mOrderBy = orderBy;
80         mPermission = permission;
81     }
82 
83     /**
84      * Builds the {@link QueryParam}.
85      */
86     public static class QueryBuilder {
87         public static final String AND = "AND";
88         public static final String OR = "OR";
89 
90         static final String ORDER_ASC = "ASC";
91         static final String ORDER_DESC = "DESC";
92 
93         private final Uri mUri;
94 
95         private String mPermission;
96 
97         private Condition mWhere = Condition.emptyCondition();
98         private final List<String> mOrderBy = new ArrayList<>();
99         private final Set<String> mProjectionColumns = new HashSet<>();
100 
101         /**
102          *
103          * @param contentUri the content uri for querying.
104          */
QueryBuilder(Uri contentUri)105         public QueryBuilder(Uri contentUri) {
106             mUri = contentUri;
107         }
108 
109         /**
110          * Specify the projection column. Calling this function multiple times to add more columns
111          * to the projection. When the same column is added multiple times, only one column will
112          * be remembered.
113          */
project(String columnName)114         public QueryBuilder project(String columnName) {
115             mProjectionColumns.add(columnName);
116             return this;
117         }
118 
119         /**
120          * Selects all columns for projection. This function call will override all previous
121          * {@link #project(String)} call. Calling this function is optional. By default, all
122          * columns will be selected.
123          */
projectAll()124         public QueryBuilder projectAll() {
125             mProjectionColumns.clear();
126             return this;
127         }
128 
129         /**
130          * Specify the select condition.
131          *
132          * @see Condition
133          */
where(@onNull Condition condition)134         public QueryBuilder where(@NonNull Condition condition) {
135             mWhere = condition;
136             return this;
137         }
138 
orderBy(String column, String order)139         private QueryBuilder orderBy(String column, String order) {
140             mOrderBy.add(column + " " + order);
141             return this;
142         }
143 
144         /**
145          * Sorts the query result in an ascending order based on the given column.
146          * Calling this function multiple times will add additional orders.
147          * The order of calling this method matters.
148          * @param column The column to be order by.
149          */
orderAscBy(String column)150         public QueryBuilder orderAscBy(String column) {
151             return orderBy(column, ORDER_ASC);
152         }
153 
154         /**
155          * Sorts the query result in an descending order based on the given column.
156          * Calling this function multiple times will add additional orders.
157          * The order of calling this method matters.
158          * @param column The column to be order by.
159          */
orderDescBy(String column)160         public QueryBuilder orderDescBy(String column) {
161             return orderBy(column, ORDER_DESC);
162         }
163 
164         /**
165          * Specify the column and order all together.
166          * @param orderBy Should follow "{column} {order}" pattern.
167          */
orderBy(String orderBy)168         public QueryBuilder orderBy(String orderBy) {
169             mOrderBy.add(orderBy);
170             return this;
171         }
172 
173         /**Specifies the permission needed for this query.*/
checkPermission(@onNull String permission)174         public QueryBuilder checkPermission(@NonNull String permission) {
175             mPermission = permission;
176             return this;
177         }
178         /**
179          * Builds the selection condition. Use {@link #is(String, String, Object)} to create an
180          * initial condition.
181          */
182         public static class Condition {
183             private String mSelection = "";
184             private List<String> mArgs = new ArrayList<>();
185 
Condition()186             private Condition() {}
187 
emptyCondition()188             private static Condition emptyCondition() {
189                 Condition condition = new Condition();
190                 condition.mSelection = null;
191                 return condition;
192             }
193 
194             /**
195              * Creates the inital condition.
196              */
is(String columnName, String operator, @NonNull Object value)197             public static Condition is(String columnName, String operator, @NonNull Object value) {
198                 Condition condition = new Condition();
199                 condition.mSelection = condition.toSelectionString(columnName, operator);
200                 condition.mArgs.add(value.toString());
201                 return condition;
202             }
203 
204             /**
205              * Appends an "AND" condition to the existing conditions.
206              */
and(String columnName, String operator, @NonNull Object value)207             public Condition and(String columnName, String operator, @NonNull Object value) {
208                 mSelection += wrapWithSpaces(AND) + toSelectionString(columnName, operator);
209                 mArgs.add(value.toString());
210                 return this;
211             }
212 
213             /**
214              * Appends an "OR" condition to the existing conditions.
215              */
or(String columnName, String operator, @NonNull Object value)216             public Condition or(String columnName, String operator, @NonNull Object value) {
217                 mSelection += wrapWithSpaces(OR) + toSelectionString(columnName, operator);
218                 mArgs.add(value.toString());
219                 return this;
220             }
221 
getSelection()222             public String getSelection() {
223                 return mSelection;
224             }
225 
getWhereArgs()226             public String[] getWhereArgs() {
227                 return mArgs.stream().toArray(String[]::new);
228             }
229 
toSelectionString(String columnName, String op)230             static String toSelectionString(String columnName, String op) {
231                 return columnName + " " + op + " ?";
232             }
233 
wrapWithSpaces(String s)234             static String wrapWithSpaces(String s) {
235                 return " " + s + " ";
236             }
237         }
238 
239         /**
240          * Builds the QueryParam.
241          */
toQueryParam()242         public QueryParam toQueryParam() {
243             String[] projection = mProjectionColumns.isEmpty()
244                     ? null
245                     : mProjectionColumns.stream().toArray(String[]::new);
246             String orderBy = mOrderBy.stream().collect(Collectors.joining(","));
247 
248             return new QueryParam(
249                     mUri,
250                     projection,
251                     mWhere.getSelection(),
252                     mWhere.getWhereArgs(),
253                     orderBy,
254                     mPermission);
255         }
256     }
257 }
258