Move UTC timestamp methods to DateUtil class

pgpainless-core/src/main/java/org/pgpainless/util/DateUtil.java

@@ -0,0 +1,62 @@
+/*
+ * Copyright 2021 Paul Schaub.
+ *
+ * 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 org.pgpainless.util;
+
+import java.text.ParseException;
+import java.text.SimpleDateFormat;
+import java.util.Date;
+import java.util.TimeZone;
+
+public class DateUtil {
+
+    public static SimpleDateFormat UTC_PARSER = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss z");
+    static {
+        UTC_PARSER.setTimeZone(TimeZone.getTimeZone("UTC"));
+    }
+
+    /**
+     * Parse a UTC timestamp into a date.
+     *
+     * @param dateString timestamp
+     * @return date
+     */
+    public static Date parseUTCDate(String dateString) {
+        try {
+            return UTC_PARSER.parse(dateString);
+        } catch (ParseException e) {
+            return null;
+        }
+    }
+
+    /**
+     * Format a date as UTC timestamp.
+     *
+     * @param date date
+     * @return timestamp
+     */
+    public static String formatUTCDate(Date date) {
+        return UTC_PARSER.format(date);
+    }
+
+    /**
+     * Return the current date "rounded" to UTC precision.
+     *
+     * @return now
+     */
+    public static Date now() {
+        return parseUTCDate(formatUTCDate(new Date()));
+    }
+}