Add DurationUtils.zeroIfNull(Duration).

src/main/java/org/apache/commons/lang3/time/DurationUtils.java

@@ -22,6 +22,7 @@ import java.time.temporal.ChronoUnit;
 import java.util.Objects;
 import java.util.concurrent.TimeUnit;
 
+import org.apache.commons.lang3.ObjectUtils;
 import org.apache.commons.lang3.Range;
 import org.apache.commons.lang3.math.NumberUtils;
 
@@ -108,4 +109,14 @@ public class DurationUtils {
         return LONG_TO_INT_RANGE.fit(Long.valueOf(duration.toMillis())).intValue();
     }
 
+    /**
+     * Returns the given non-null value or {@link Duration#ZERO} if null. 
+     *
+     * @param duration The duration to test.
+     * @return The given duration or {@link Duration#ZERO}.
+     */
+    public static Duration zeroIfNull(final Duration duration) {
+        return ObjectUtils.defaultIfNull(duration, Duration.ZERO);
+    }
+
 }

src/test/java/org/apache/commons/lang3/time/DurationUtilsTest.java

@@ -86,4 +86,10 @@ public class DurationUtilsTest {
         assertEquals(Integer.MIN_VALUE, DurationUtils.toMillisInt(Duration.ofNanos(Long.MIN_VALUE)));
         assertEquals(Integer.MAX_VALUE, DurationUtils.toMillisInt(Duration.ofNanos(Long.MAX_VALUE)));
     }
+
+    @Test
+    public void testZeroIfNull() {
+        assertEquals(Duration.ZERO, DurationUtils.zeroIfNull(null));
+        assertEquals(Duration.ofDays(1), DurationUtils.zeroIfNull(Duration.ofDays(1)));
+    }
 }