JAVA-2335: Null value in ServerAddress list should cause an IllegalArgumentException expection rather than a NullPointerException

Author: jyemin

driver-core/src/main/com/mongodb/connection/ClusterSettings.java

@@ -102,6 +102,7 @@ public Builder hosts(final List<ServerAddress> hosts) {
             }
             Set<ServerAddress> hostsSet = new LinkedHashSet<ServerAddress>(hosts.size());
             for (ServerAddress host : hosts) {
+                notNull("host", host);
                 hostsSet.add(new ServerAddress(host.getHost(), host.getPort()));
             }
             this.hosts = Collections.unmodifiableList(new ArrayList<ServerAddress>(hostsSet));

driver-core/src/test/unit/com/mongodb/connection/ClusterSettingsSpecification.groovy

@@ -213,6 +213,14 @@ class ClusterSettingsSpecification extends Specification {
         thrown(IllegalArgumentException)
     }
 
+    def 'should throws if hosts list contains null value'() {
+        when:
+        ClusterSettings.builder().hosts([null]).build();
+
+        then:
+        thrown(IllegalArgumentException)
+    }
+
     def 'should remove duplicate hosts'() {
         when:
         def settings = ClusterSettings.builder().hosts([new ServerAddress('server1'),