Home | History | Annotate | Download | only in core 
      1 /*
      2  * Copyright (C) 2011 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.example.android.voicemail.common.core;
     18 
     19 import static com.example.android.voicemail.common.utils.DbQueryUtils.concatenateClausesWithAnd;
     20 import static com.example.android.voicemail.common.utils.DbQueryUtils.concatenateClausesWithOr;
     21 import static com.example.android.voicemail.common.utils.DbQueryUtils.getEqualityClause;
     22 
     23 import android.provider.VoicemailContract.Voicemails;
     24 import android.text.TextUtils;
     25 
     26 import java.util.ArrayList;
     27 import java.util.List;
     28 
     29 /**
     30  * Factory class to create {@link VoicemailFilter} objects for various filtering needs.
     31  * <p>
     32  * Factory methods like {@link #createWithReadStatus(boolean)} and
     33  * {@link #createWithMatchingFields(Voicemail)} can be used to create a voicemail filter that
     34  * matches the value of the specific field.
     35  * <p>
     36  * It is possible to combine multiple filters with OR or AND operation using the methods
     37  * {@link #createWithOrOf(VoicemailFilter...)} and {@link #createWithAndOf(VoicemailFilter...)}
     38  * respectively.
     39  * <p>
     40  * {@link #createWithWhereClause(String)} can be used to create an arbitrary filter for a specific
     41  * where clause. Using this method requires the knowledge of the name of columns used in voicemail
     42  * content provider database and is therefore less recommended.
     43  */
     44 public class VoicemailFilterFactory {
     45     /**
     46      * Creates a voicemail filter with the specified where clause. Use this method only if you know
     47      * and want to directly use the column names of the content provider. For most of the usages
     48      * one of the other factory methods should be good enough.
     49      */
     50     public static VoicemailFilter createWithWhereClause(final String whereClause) {
     51         return new VoicemailFilter() {
     52           @Override
     53           public String getWhereClause() {
     54             return TextUtils.isEmpty(whereClause) ? null : whereClause;
     55           }
     56           @Override
     57           public String toString() {
     58               return getWhereClause();
     59           }
     60         };
     61     }
     62 
     63     /** Creates a filter with fields matching the ones set in the supplied voicemail object. */
     64     public static VoicemailFilter createWithMatchingFields(Voicemail fieldMatch) {
     65         if (fieldMatch == null) {
     66             throw new IllegalArgumentException("Cannot create filter null fieldMatch");
     67         }
     68         return VoicemailFilterFactory.createWithWhereClause(
     69                 getWhereClauseForMatchingFields(fieldMatch));
     70     }
     71 
     72     /** Creates a voicemail filter with the specified read status. */
     73     public static VoicemailFilter createWithReadStatus(boolean isRead) {
     74         return createWithMatchingFields(
     75                 VoicemailImpl.createEmptyBuilder().setIsRead(isRead).build());
     76     }
     77 
     78     /** Combine multiple filters with OR clause. */
     79     public static VoicemailFilter createWithAndOf(VoicemailFilter... filters) {
     80         return createWithWhereClause(concatenateClausesWithAnd(getClauses(filters)));
     81     }
     82 
     83     /** Combine multiple filters with AND clause. */
     84     public static VoicemailFilter createWithOrOf(VoicemailFilter... filters) {
     85         return createWithWhereClause(concatenateClausesWithOr(getClauses(filters)));
     86     }
     87 
     88     private static String[] getClauses(VoicemailFilter[] filters) {
     89         String[] clauses = new String[filters.length];
     90         for (int i = 0; i < filters.length; ++i) {
     91             clauses[i] = filters[i].getWhereClause();
     92         }
     93         return clauses;
     94     }
     95 
     96     private static String getWhereClauseForMatchingFields(Voicemail fieldMatch) {
     97         List<String> clauses = new ArrayList<String>();
     98         if (fieldMatch.hasRead()) {
     99             clauses.add(getEqualityClause(Voicemails.IS_READ, fieldMatch.isRead() ? "1" : "0"));
    100         }
    101         if (fieldMatch.hasNumber()) {
    102             clauses.add(getEqualityClause(Voicemails.NUMBER, fieldMatch.getNumber()));
    103         }
    104         if (fieldMatch.hasSourcePackage()) {
    105             clauses.add(getEqualityClause(Voicemails.SOURCE_PACKAGE,
    106                     fieldMatch.getSourcePackage()));
    107         }
    108         if (fieldMatch.hasSourceData()) {
    109             clauses.add(getEqualityClause(Voicemails.SOURCE_DATA, fieldMatch.getSourceData()));
    110         }
    111         if (fieldMatch.hasDuration()) {
    112             clauses.add(getEqualityClause(Voicemails.DURATION,
    113                     Long.toString(fieldMatch.getDuration())));
    114         }
    115         if (fieldMatch.hasTimestampMillis()) {
    116             clauses.add(getEqualityClause(Voicemails.DATE,
    117                     Long.toString(fieldMatch.getTimestampMillis())));
    118         }
    119         // Empty filter.
    120         if (clauses.size() == 0) {
    121             return null;
    122         }
    123         return concatenateClausesWithAnd(clauses.toArray(new String[0]));
    124     }
    125 }
    126