diff --git a/smack-extensions/src/main/java/org/jivesoftware/smackx/jingle/transports/jingle_s5b/elements/JingleS5BTransport.java b/smack-extensions/src/main/java/org/jivesoftware/smackx/jingle/transports/jingle_s5b/elements/JingleS5BTransport.java
index 355255c2d..a70b5d9a6 100644
--- a/smack-extensions/src/main/java/org/jivesoftware/smackx/jingle/transports/jingle_s5b/elements/JingleS5BTransport.java
+++ b/smack-extensions/src/main/java/org/jivesoftware/smackx/jingle/transports/jingle_s5b/elements/JingleS5BTransport.java
@@ -93,8 +93,8 @@ public class JingleS5BTransport extends JingleContentTransport {
         private String streamId;
         private String dstAddr;
         private Bytestream.Mode mode;
-        private ArrayList<JingleContentTransportCandidate> candidates = new ArrayList<>();
-        private JingleContentTransportInfo info = null;
+        private final ArrayList<JingleContentTransportCandidate> candidates = new ArrayList<>();
+        private JingleContentTransportInfo info;
 
         public Builder setStreamId(String sid) {
             this.streamId = sid;
@@ -112,11 +112,22 @@ public class JingleS5BTransport extends JingleContentTransport {
         }
 
         public Builder addTransportCandidate(JingleS5BTransportCandidate candidate) {
+            if (info != null) {
+                throw new IllegalStateException("Builder has already an info set. " +
+                        "The transport can only have either an info or transport candidates, not both.");
+            }
             this.candidates.add(candidate);
             return this;
         }
 
         public Builder setTransportInfo(JingleContentTransportInfo info) {
+            if (!candidates.isEmpty()) {
+                throw new IllegalStateException("Builder has already at least one candidate set. " +
+                        "The transport can only have either an info or transport candidates, not both.");
+            }
+            if (this.info != null) {
+                throw new IllegalStateException("Builder has already an info set.");
+            }
             this.info = info;
             return this;
         }
diff --git a/smack-extensions/src/test/java/org/jivesoftware/smackx/jingle/transports/jingle_s5b/JingleS5BTransportTest.java b/smack-extensions/src/test/java/org/jivesoftware/smackx/jingle/transports/jingle_s5b/JingleS5BTransportTest.java
index f9bf1e94d..44b450ca5 100644
--- a/smack-extensions/src/test/java/org/jivesoftware/smackx/jingle/transports/jingle_s5b/JingleS5BTransportTest.java
+++ b/smack-extensions/src/test/java/org/jivesoftware/smackx/jingle/transports/jingle_s5b/JingleS5BTransportTest.java
@@ -16,9 +16,15 @@
  */
 package org.jivesoftware.smackx.jingle.transports.jingle_s5b;
 
+<<<<<<< HEAD
 import static junit.framework.TestCase.assertNotNull;
 import static junit.framework.TestCase.assertNull;
 import static org.junit.Assert.assertEquals;
+=======
+import static junit.framework.TestCase.assertNull;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
+>>>>>>> js5btbFixes
 
 import org.jivesoftware.smack.test.util.SmackTestSuite;
 import org.jivesoftware.smack.test.util.TestUtils;
@@ -128,7 +134,11 @@ public class JingleS5BTransportTest extends SmackTestSuite {
         JingleS5BTransport proxyErrorTransport = new JingleS5BTransportProvider()
                 .parse(TestUtils.getParser(proxyError));
         assertNull(proxyErrorTransport.getDestinationAddress());
+<<<<<<< HEAD
         assertNotNull(proxyErrorTransport.getInfo());
+=======
+        assertNotNull(candidateErrorTransport.getInfo());
+>>>>>>> js5btbFixes
         assertEquals("vj3hs98y", proxyErrorTransport.getStreamId());
         assertEquals(JingleS5BTransportInfo.ProxyError(),
                 proxyErrorTransport.getInfo());
@@ -140,7 +150,11 @@ public class JingleS5BTransportTest extends SmackTestSuite {
                         "</transport>";
         JingleS5BTransport candidateUsedTransport = new JingleS5BTransportProvider()
                 .parse(TestUtils.getParser(candidateUsed));
+<<<<<<< HEAD
         assertNotNull(candidateUsedTransport.getInfo());
+=======
+        assertNotNull(candidateErrorTransport.getInfo());
+>>>>>>> js5btbFixes
         assertEquals(JingleS5BTransportInfo.CandidateUsed("hr65dqyd"),
                 candidateUsedTransport.getInfo());
         assertEquals("hr65dqyd",
@@ -154,7 +168,11 @@ public class JingleS5BTransportTest extends SmackTestSuite {
                         "</transport>";
         JingleS5BTransport candidateActivatedTransport = new JingleS5BTransportProvider()
                 .parse(TestUtils.getParser(candidateActivated));
+<<<<<<< HEAD
         assertNotNull(candidateActivatedTransport.getInfo());
+=======
+        assertNotNull(candidateErrorTransport.getInfo());
+>>>>>>> js5btbFixes
         assertEquals(JingleS5BTransportInfo.CandidateActivated("hr65dqyd"),
                 candidateActivatedTransport.getInfo());
         assertEquals("hr65dqyd",