RelativeDateFormatter: Use Instant instead of date

Errorprone suggest to use the more modern java.time.Instant instead of
the older Date API.

Offer a variant of RelativeDateFormatter#format method for Instants.

Change-Id: I536230327ec7b617958191fbe36f98b1294f6d2e

3 files changed, 26 insertions, 7 deletions

diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/util/RelativeDateFormatterTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/util/RelativeDateFormatterTest.java
index 214bbca944..a927d8dbef 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/util/RelativeDateFormatterTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/util/RelativeDateFormatterTest.java
@@ -16,7 +16,7 @@ import static org.eclipse.jgit.util.RelativeDateFormatter.SECOND_IN_MILLIS;
 import static org.eclipse.jgit.util.RelativeDateFormatter.YEAR_IN_MILLIS;
 import static org.junit.Assert.assertEquals;
 
-import java.util.Date;
+import java.time.Instant;
 
 import org.eclipse.jgit.junit.MockSystemReader;
 import org.junit.After;
@@ -37,9 +37,9 @@ public class RelativeDateFormatterTest {
 
 	private static void assertFormat(long ageFromNow, long timeUnit,
 			String expectedFormat) {
-		Date d = new Date(SystemReader.getInstance().getCurrentTime()
-				- ageFromNow * timeUnit);
-		String s = RelativeDateFormatter.format(d);
+		long millis = ageFromNow * timeUnit;
+		Instant aTime = SystemReader.getInstance().now().minusMillis(millis);
+		String s = RelativeDateFormatter.format(aTime);
 		assertEquals(expectedFormat, s);
 	}
 
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/util/GitDateFormatter.java b/org.eclipse.jgit/src/org/eclipse/jgit/util/GitDateFormatter.java
index e6bf497ac4..524126b098 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/util/GitDateFormatter.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/util/GitDateFormatter.java
@@ -148,7 +148,7 @@ public class GitDateFormatter {
 			return String.format("%d %s%02d%02d", //$NON-NLS-1$
 					ident.getWhen().getTime() / 1000, sign, hours, minutes);
 		case RELATIVE:
-			return RelativeDateFormatter.format(ident.getWhen());
+			return RelativeDateFormatter.format(ident.getWhenAsInstant());
 		case LOCALELOCAL:
 		case LOCAL:
 			dateTimeInstance.setTimeZone(SystemReader.getInstance()
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/util/RelativeDateFormatter.java b/org.eclipse.jgit/src/org/eclipse/jgit/util/RelativeDateFormatter.java
index 5611b1e78e..b6b19e0e7b 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/util/RelativeDateFormatter.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/util/RelativeDateFormatter.java
@@ -10,6 +10,8 @@
 package org.eclipse.jgit.util;
 
 import java.text.MessageFormat;
+import java.time.Duration;
+import java.time.Instant;
 import java.util.Date;
 
 import org.eclipse.jgit.internal.JGitText;
@@ -42,12 +44,29 @@ public class RelativeDateFormatter {
 	 * @return age of given {@link java.util.Date} compared to now formatted in
 	 *         the same relative format as returned by
 	 *         {@code git log --relative-date}
+	 * @deprecated Use {@link #format(Instant)} instead.
 	 */
+	@Deprecated(since = "7.2")
 	@SuppressWarnings("boxing")
 	public static String format(Date when) {
+		return format(when.toInstant());
+	}
 
-		long ageMillis = SystemReader.getInstance().getCurrentTime()
-				- when.getTime();
+	/**
+	 * Get age of given {@link java.time.Instant} compared to now formatted in the
+	 * same relative format as returned by {@code git log --relative-date}
+	 *
+	 * @param when
+	 *            an instant to format
+	 * @return age of given instant compared to now formatted in
+	 *         the same relative format as returned by
+	 *         {@code git log --relative-date}
+	 * @since 7.2
+	 */
+	@SuppressWarnings("boxing")
+	public static String format(Instant when) {
+		long ageMillis = Duration
+				.between(when, SystemReader.getInstance().now()).toMillis();
 
 		// shouldn't happen in a perfect world
 		if (ageMillis < 0)