1 /*
2  * Copyright (C) 2017 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.service.autofill;
18 
19 import static android.view.autofill.Helper.sDebug;
20 
21 import android.annotation.NonNull;
22 import android.annotation.TestApi;
23 import android.os.Parcel;
24 import android.os.Parcelable;
25 import android.util.Log;
26 import android.view.autofill.AutofillId;
27 
28 import com.android.internal.util.Preconditions;
29 
30 import java.util.regex.Pattern;
31 
32 /**
33  * Defines if a field is valid based on a regular expression (regex).
34  *
35  * <p>See {@link SaveInfo.Builder#setValidator(Validator)} for examples.
36  */
37 public final class RegexValidator extends InternalValidator implements Validator, Parcelable {
38 
39     private static final String TAG = "RegexValidator";
40 
41     private final AutofillId mId;
42     private final Pattern mRegex;
43 
44     /**
45      * Default constructor.
46      *
47      * @param id id of the field whose regex is applied to.
48      * @param regex regular expression that defines the result of the validator: if the regex
49      * matches the contents of the field identified by {@code id}, it returns {@code true};
50      * otherwise, it returns {@code false}.
51       */
RegexValidator(@onNull AutofillId id, @NonNull Pattern regex)52     public RegexValidator(@NonNull AutofillId id, @NonNull Pattern regex) {
53         mId = Preconditions.checkNotNull(id);
54         mRegex = Preconditions.checkNotNull(regex);
55     }
56 
57     /** @hide */
58     @Override
59     @TestApi
isValid(@onNull ValueFinder finder)60     public boolean isValid(@NonNull ValueFinder finder) {
61         final String value = finder.findByAutofillId(mId);
62         if (value == null) {
63             Log.w(TAG, "No view for id " + mId);
64             return false;
65         }
66 
67         final boolean valid = mRegex.matcher(value).matches();
68         if (sDebug) Log.d(TAG, "isValid(): " + valid);
69         return valid;
70     }
71 
72     /////////////////////////////////////
73     // Object "contract" methods. //
74     /////////////////////////////////////
75     @Override
toString()76     public String toString() {
77         if (!sDebug) return super.toString();
78 
79         return "RegexValidator: [id=" + mId + ", regex=" + mRegex + "]";
80     }
81 
82     /////////////////////////////////////
83     // Parcelable "contract" methods. //
84     /////////////////////////////////////
85     @Override
describeContents()86     public int describeContents() {
87         return 0;
88     }
89 
90     @Override
writeToParcel(Parcel parcel, int flags)91     public void writeToParcel(Parcel parcel, int flags) {
92         parcel.writeParcelable(mId, flags);
93         parcel.writeSerializable(mRegex);
94     }
95 
96     public static final @android.annotation.NonNull Parcelable.Creator<RegexValidator> CREATOR =
97             new Parcelable.Creator<RegexValidator>() {
98         @Override
99         public RegexValidator createFromParcel(Parcel parcel) {
100             return new RegexValidator(parcel.readParcelable(null),
101                     (Pattern) parcel.readSerializable());
102         }
103 
104         @Override
105         public RegexValidator[] newArray(int size) {
106             return new RegexValidator[size];
107         }
108     };
109 }
110