refactor: add null check for BroadcastDomainType retrievals (apache#11572)

Signed-off-by: Abhishek Kumar <abhishek.mrt22@gmail.com>

Author: shwstppr

api/src/main/java/com/cloud/network/Networks.java

@@ -78,7 +78,7 @@ public <T> URI toUri(T value) {
             }
             @Override
             public String getValueFrom(URI uri) {
-                return uri.getAuthority();
+                return uri == null ? null : uri.getAuthority();
             }
         },
         Vswitch("vs", String.class), LinkLocal(null, null), Vnet("vnet", Long.class), Storage("storage", Integer.class), Lswitch("lswitch", String.class) {
@@ -96,7 +96,7 @@ public <T> URI toUri(T value) {
              */
             @Override
             public String getValueFrom(URI uri) {
-                return uri.getSchemeSpecificPart();
+                return uri == null ? null : uri.getSchemeSpecificPart();
             }
         },
         Mido("mido", String.class), Pvlan("pvlan", String.class),
@@ -177,7 +177,7 @@ public <T> URI toUri(T value) {
          * @return the scheme as BroadcastDomainType
          */
         public static BroadcastDomainType getSchemeValue(URI uri) {
-            return toEnumValue(uri.getScheme());
+            return toEnumValue(uri == null ? null : uri.getScheme());
         }
 
         /**
@@ -191,7 +191,7 @@ public static BroadcastDomainType getTypeOf(String str) throws URISyntaxExceptio
             if (com.cloud.dc.Vlan.UNTAGGED.equalsIgnoreCase(str)) {
                 return Native;
             }
-            return getSchemeValue(new URI(str));
+            return getSchemeValue(str == null ? null : new URI(str));
         }
 
         /**
@@ -220,7 +220,7 @@ public static BroadcastDomainType toEnumValue(String scheme) {
          * @return the host part as String
          */
         public String getValueFrom(URI uri) {
-            return uri.getHost();
+            return uri == null ? null : uri.getHost();
         }
 
         /**
@@ -243,7 +243,7 @@ public static String getValue(URI uri) {
          * @throws URISyntaxException the string is not even an uri
          */
         public static String getValue(String uriString) throws URISyntaxException {
-            return getValue(new URI(uriString));
+            return getValue(uriString == null ? null : new URI(uriString));
         }
 
         /**

api/src/test/java/com/cloud/network/NetworksTest.java

@@ -37,6 +37,24 @@ public class NetworksTest {
     public void setUp() {
     }
 
+    @Test
+    public void nullBroadcastDomainTypeTest() throws URISyntaxException {
+        BroadcastDomainType type = BroadcastDomainType.getTypeOf(null);
+        Assert.assertEquals("a null uri should mean a broadcasttype of undecided", BroadcastDomainType.UnDecided, type);
+    }
+
+    @Test
+    public void nullBroadcastDomainTypeValueTest() {
+        URI uri = null;
+        Assert.assertNull(BroadcastDomainType.getValue(uri));
+    }
+
+    @Test
+    public void nullBroadcastDomainTypeStringValueTest() throws URISyntaxException {
+        String uriString = null;
+        Assert.assertNull(BroadcastDomainType.getValue(uriString));
+    }
+
     @Test
     public void emptyBroadcastDomainTypeTest() throws URISyntaxException {
         BroadcastDomainType type = BroadcastDomainType.getTypeOf("");