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