NamingContext.getNameIfPresent should not fail if name is missing

Also makes InterfaceChangeNotificationProducer notification translation
code more defensive.

The issue was revealed by HC2VPP-216 and HC2VPP-220.

Change-Id: I20792a51743ae621d86c1b9066d680bc2303ed82
Signed-off-by: Marek Gradzki <mgradzki@cisco.com>

1 files changed, 15 insertions, 5 deletions

diff --git a/vpp-common/vpp-translate-utils/src/main/java/io/fd/hc2vpp/common/translate/util/NamingContext.java b/vpp-common/vpp-translate-utils/src/main/java/io/fd/hc2vpp/common/translate/util/NamingContext.java
index 5e0eea71b..8965de616 100644
--- a/vpp-common/vpp-translate-utils/src/main/java/io/fd/hc2vpp/common/translate/util/NamingContext.java
+++ b/vpp-common/vpp-translate-utils/src/main/java/io/fd/hc2vpp/common/translate/util/NamingContext.java
@@ -22,7 +22,9 @@ import static com.google.common.base.Preconditions.checkState;
 import com.google.common.base.Optional;
 import io.fd.honeycomb.translate.MappingContext;
 import io.fd.honeycomb.translate.util.RWUtils;
+import java.util.List;
 import java.util.stream.Collector;
+import java.util.stream.Collectors;
 import javax.annotation.Nonnull;
 import org.opendaylight.yang.gen.v1.urn.honeycomb.params.xml.ns.yang.naming.context.rev160513.Contexts;
 import org.opendaylight.yang.gen.v1.urn.honeycomb.params.xml.ns.yang.naming.context.rev160513.contexts.NamingContextKey;
@@ -92,13 +94,21 @@ public final class NamingContext implements AutoCloseable {
     public synchronized Optional<String> getNameIfPresent(final int index,
                                                           @Nonnull final MappingContext mappingContext) {
         final Optional<Mappings> read = mappingContext.read(namingContextIid.child(Mappings.class));
+        if (!read.isPresent()) {
+            return Optional.absent();
+        }
 
-        return read.isPresent()
-                ? Optional.of(read.get().getMapping().stream()
+        final List<Mapping> mappings = read.get().getMapping().stream()
                 .filter(mapping -> mapping.getIndex().equals(index))
-                .collect(SINGLE_ITEM_COLLECTOR)
-                .getName())
-                : Optional.absent();
+                .collect(Collectors.toList());
+
+        if (mappings.size() > 1) {
+            throw new IllegalStateException("Multiple mappings defined with index=" + index + ": " + mappings);
+        } else if (mappings.size() == 1) {
+            return Optional.of(mappings.get(0).getName());
+        } else {
+            return Optional.absent();
+        }
     }
 
     /**