/*
* Copyright 2022 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package androidx.appsearch.utils;
import static androidx.annotation.RestrictTo.Scope.LIBRARY;
import androidx.annotation.NonNull;
import androidx.annotation.RestrictTo;
import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Locale;
/**
* Helper class used to validate date time formats.
*
* @hide
*/
@RestrictTo(LIBRARY)
public final class DateTimeFormatValidator {
private DateTimeFormatValidator() {}
/**
* Returns true if the date string matches yyyy-MM-dd
*/
public static boolean validateISO8601Date(@NonNull String dateString) {
return validateDateFormat("yyyy-MM-dd", dateString);
}
/**
* Returns true if the date string matches yyyy-MM-ddTHH:mm:ss
*/
public static boolean validateISO8601DateTime(@NonNull String dateString) {
return validateDateFormat("yyyy-MM-dd'T'HH:mm", dateString)
|| validateDateFormat("yyyy-MM-dd'T'HH:mm:ss", dateString);
}
/**
* Returns true if the date string matches the provided format exactly.
*/
public static boolean validateDateFormat(@NonNull String format, @NonNull String dateString) {
// ISO 8601 DateTime format must be represented using arabic numerals (0-9). en-US is
// one of many locales that uses arabic numerals, therefore it is used during formatting.
// Even if the user's device is not in the en-US locale, this will still work since ISO
// 8601 is an international standard, and does not change based on locales.
DateFormat dateFormat = new SimpleDateFormat(format, Locale.US);
dateFormat.setLenient(false);
try {
Date date = dateFormat.parse(dateString);
// ensure exact match
if (date == null || !dateString.equals(dateFormat.format(date))) {
return false;
}
} catch (ParseException e) {
return false;
}
return true;
}
}