Use modern Java time APIs

Author: oschwald

CHANGELOG.md

@@ -10,15 +10,16 @@ CHANGELOG
   2GB ByteBuffer limit. Files under 2GB continue to use a single ByteBuffer
   for optimal performance. Requested by nonetallt. GitHub #154. Fixed by
   Silvano Cerza. GitHub #289.
+* `Metadata.getBuildDate()` has been replaced with `buildTime()`, which returns
+  `java.time.Instant` instead of `java.util.Date`. The instant represents the
+  database build time in UTC.
 * `DatabaseRecord`, `Metadata`, `Network`, and internal `DecodedValue` classes
   have been converted to records. The following API changes were made:
   * `DatabaseRecord.getData()` and `DatabaseRecord.getNetwork()` have been
     replaced with record accessor methods `data()` and `network()`.
-  * `Metadata.getBuildDate()` has been renamed to `buildDate()` to follow record
-    naming conventions. All other simple getter methods on `Metadata` (e.g.,
-    `getBinaryFormatMajorVersion()`, `getDatabaseType()`, etc.) have been
-    replaced with their corresponding record accessor methods (e.g.,
-    `binaryFormatMajorVersion()`, `databaseType()`, etc.).
+  * Simple getter methods on `Metadata` (e.g., `getBinaryFormatMajorVersion()`,
+    `getDatabaseType()`, etc.) have been replaced with their corresponding record
+    accessor methods (e.g., `binaryFormatMajorVersion()`, `databaseType()`, etc.).
   * `Network.getNetworkAddress()` and `Network.getPrefixLength()` have been
     replaced with record accessor methods `networkAddress()` and `prefixLength()`.
 

src/main/java/com/maxmind/db/Metadata.java

@@ -1,7 +1,7 @@
 package com.maxmind.db;
 
 import java.math.BigInteger;
-import java.util.Date;
+import java.time.Instant;
 import java.util.List;
 import java.util.Map;
 
@@ -46,9 +46,9 @@ public record Metadata(
     public Metadata {}
 
     /**
-     * @return the date of the database build.
+     * @return the instant of the database build in UTC.
      */
-    public Date buildDate() {
-        return new Date(buildEpoch.longValue() * 1000);
+    public Instant buildTime() {
+        return Instant.ofEpochSecond(buildEpoch.longValue());
     }
 }

src/test/java/com/maxmind/db/ReaderTest.java

@@ -19,9 +19,11 @@
 import java.math.BigInteger;
 import java.net.InetAddress;
 import java.net.UnknownHostException;
+import java.time.Instant;
+import java.time.LocalDate;
+import java.time.ZoneOffset;
 import java.util.ArrayList;
 import java.util.Arrays;
-import java.util.Calendar;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
@@ -1295,10 +1297,11 @@ private void testMetadata(Reader reader, int ipVersion, long recordSize) {
         assertEquals(description, metadata.description());
         assertEquals(recordSize, metadata.recordSize());
 
-        var cal = Calendar.getInstance();
-        cal.set(2014, Calendar.JANUARY, 1);
+        var january2014 = LocalDate.of(2014, 1, 1)
+                .atStartOfDay(ZoneOffset.UTC)
+                .toInstant();
 
-        assertTrue(metadata.buildDate().compareTo(cal.getTime()) > 0);
+        assertTrue(metadata.buildTime().isAfter(january2014));
     }
 
     private void testIpV4(Reader reader, File file) throws IOException {