Make nullToEmpty return immutable empty lists

[genius.git] / alivenessmonitor / alivenessmonitor-impl / src / main / java / org / opendaylight / genius / alivenessmonitor / utils / AlivenessMonitorUtil.java

diff --git a/alivenessmonitor/alivenessmonitor-impl/src/main/java/org/opendaylight/genius/alivenessmonitor/utils/AlivenessMonitorUtil.java b/alivenessmonitor/alivenessmonitor-impl/src/main/java/org/opendaylight/genius/alivenessmonitor/utils/AlivenessMonitorUtil.java
index aeb29f37e5888423afc8ac9be58c1476c776454d..ed16d1a59a11fabba3e70374b36dde9c26b4fde4 100644 (file)
--- a/alivenessmonitor/alivenessmonitor-impl/src/main/java/org/opendaylight/genius/alivenessmonitor/utils/AlivenessMonitorUtil.java
+++ b/alivenessmonitor/alivenessmonitor-impl/src/main/java/org/opendaylight/genius/alivenessmonitor/utils/AlivenessMonitorUtil.java
@@ -7,7 +7,12 @@
  */
 package org.opendaylight.genius.alivenessmonitor.utils;
 
+import static java.util.Collections.emptyList;
+
 import java.util.Collection;
+import java.util.List;
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
 import org.apache.commons.lang3.StringUtils;
 import org.opendaylight.genius.ipv6util.api.Ipv6Util;
 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.yang.types.rev130715.PhysAddress;
@@ -94,4 +99,10 @@ public final class AlivenessMonitorUtil {
         }
         return errorText.toString();
     }
+
+    // TODO Replace this with mdsal's DataObjectUtils.nullToEmpty when upgrading to mdsal 3.0.2
+    @Nonnull
+    public static <T> List<T> nullToEmpty(final @Nullable List<T> input) {
+        return input != null ? input : emptyList();
+    }
 }