Fix Java9SslEngine implementation of ApplicationProtocolAccessor and …

handler/src/main/java/io/netty/handler/ssl/ApplicationProtocolAccessor.java

@@ -26,5 +26,5 @@ interface ApplicationProtocolAccessor {
      * @return the application-level protocol name or
      *         {@code null} if the negotiation failed or the client does not have ALPN/NPN extension
      */
-    String getApplicationProtocol();
+    String getNegotiatedApplicationProtocol();
 }

handler/src/main/java/io/netty/handler/ssl/Java9SslEngine.java

@@ -150,17 +150,25 @@ public SSLEngineResult unwrap(ByteBuffer src, ByteBuffer[] dst, int offset, int
     }
 
     @Override
-    void setApplicationProtocol(String applicationProtocol) {
+    void setNegotiatedApplicationProtocol(String applicationProtocol) {
         // Do nothing as this is handled internally by the Java9 implementation of SSLEngine.
     }
 
     @Override
-    public String getApplicationProtocol() {
-        return Java9SslUtils.getApplicationProtocol(getWrappedEngine());
+    public String getNegotiatedApplicationProtocol() {
+        String protocol = getApplicationProtocol();
+        if (protocol != null) {
+            return protocol.isEmpty() ? null : protocol;
+        }
+        return protocol;
     }
 
     // These methods will override the methods defined by Java 9. As we compile with Java8 we can not add
     // @Override annotations here.
+    public String getApplicationProtocol() {
+        return Java9SslUtils.getApplicationProtocol(getWrappedEngine());
+    }
+
     public String getHandshakeApplicationProtocol() {
         return Java9SslUtils.getHandshakeApplicationProtocol(getWrappedEngine());
     }

handler/src/main/java/io/netty/handler/ssl/JdkBaseApplicationProtocolNegotiator.java

@@ -137,22 +137,22 @@ static class NoFailProtocolSelector implements ProtocolSelector {
 
         @Override
         public void unsupported() {
-            engineWrapper.setApplicationProtocol(null);
+            engineWrapper.setNegotiatedApplicationProtocol(null);
         }
 
         @Override
         public String select(List<String> protocols) throws Exception {
             for (String p : supportedProtocols) {
                 if (protocols.contains(p)) {
-                    engineWrapper.setApplicationProtocol(p);
+                    engineWrapper.setNegotiatedApplicationProtocol(p);
                     return p;
                 }
             }
             return noSelectMatchFound();
         }
 
         public String noSelectMatchFound() throws Exception {
-            engineWrapper.setApplicationProtocol(null);
+            engineWrapper.setNegotiatedApplicationProtocol(null);
             return null;
         }
     }
@@ -179,13 +179,13 @@ private static class NoFailProtocolSelectionListener implements ProtocolSelectio
 
         @Override
         public void unsupported() {
-            engineWrapper.setApplicationProtocol(null);
+            engineWrapper.setNegotiatedApplicationProtocol(null);
         }
 
         @Override
         public void selected(String protocol) throws Exception {
             if (supportedProtocols.contains(protocol)) {
-                engineWrapper.setApplicationProtocol(protocol);
+                engineWrapper.setNegotiatedApplicationProtocol(protocol);
             } else {
                 noSelectedMatchFound(protocol);
             }

handler/src/main/java/io/netty/handler/ssl/JdkSslEngine.java

@@ -33,11 +33,11 @@ class JdkSslEngine extends SSLEngine implements ApplicationProtocolAccessor {
     }
 
     @Override
-    public String getApplicationProtocol() {
+    public String getNegotiatedApplicationProtocol() {
         return applicationProtocol;
     }
 
-    void setApplicationProtocol(String applicationProtocol) {
+    void setNegotiatedApplicationProtocol(String applicationProtocol) {
         this.applicationProtocol = applicationProtocol;
     }
 

handler/src/main/java/io/netty/handler/ssl/ReferenceCountedOpenSslEngine.java

@@ -1829,7 +1829,7 @@ final boolean checkSniHostnameMatch(String hostname) {
     }
 
     @Override
-    public String getApplicationProtocol() {
+    public String getNegotiatedApplicationProtocol() {
         return applicationProtocol;
     }
 

handler/src/main/java/io/netty/handler/ssl/SslHandler.java

@@ -66,7 +66,6 @@
 import javax.net.ssl.SSLEngineResult.HandshakeStatus;
 import javax.net.ssl.SSLEngineResult.Status;
 import javax.net.ssl.SSLException;
-import javax.net.ssl.SSLSession;
 
 import static io.netty.buffer.ByteBufUtil.ensureWritableSuccess;
 import static io.netty.handler.ssl.SslUtils.getEncryptedPacketLength;
@@ -578,7 +577,7 @@ public String applicationProtocol() {
             return null;
         }
 
-        return ((ApplicationProtocolAccessor) engine).getApplicationProtocol();
+        return ((ApplicationProtocolAccessor) engine).getNegotiatedApplicationProtocol();
     }
 
     /**

handler/src/test/java/io/netty/handler/ssl/SSLEngineTest.java

@@ -42,6 +42,7 @@
 import io.netty.util.concurrent.Promise;
 import io.netty.util.internal.EmptyArrays;
 import io.netty.util.internal.PlatformDependent;
+import io.netty.util.internal.StringUtil;
 import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
@@ -996,10 +997,8 @@ protected void runTest(String expectedApplicationProtocol) throws Exception {
         try {
             writeAndVerifyReceived(clientMessage.retain(), clientChannel, serverLatch, serverReceiver);
             writeAndVerifyReceived(serverMessage.retain(), serverConnectedChannel, clientLatch, clientReceiver);
-            if (expectedApplicationProtocol != null) {
-                verifyApplicationLevelProtocol(clientChannel, expectedApplicationProtocol);
-                verifyApplicationLevelProtocol(serverConnectedChannel, expectedApplicationProtocol);
-            }
+            verifyApplicationLevelProtocol(clientChannel, expectedApplicationProtocol);
+            verifyApplicationLevelProtocol(serverConnectedChannel, expectedApplicationProtocol);
         } finally {
             clientMessage.release();
             serverMessage.release();
@@ -1011,6 +1010,14 @@ private static void verifyApplicationLevelProtocol(Channel channel, String expec
         assertNotNull(handler);
         String appProto = handler.applicationProtocol();
         assertEquals(appProto, expectedApplicationProtocol);
+
+        SSLEngine engine = handler.engine();
+        if (engine instanceof Java9SslEngine) {
+            // Also verify the Java9 exposed method.
+            Java9SslEngine java9SslEngine = (Java9SslEngine) engine;
+            assertEquals(expectedApplicationProtocol == null ? StringUtil.EMPTY_STRING : expectedApplicationProtocol,
+                    java9SslEngine.getApplicationProtocol());
+        }
     }
 
     private static void writeAndVerifyReceived(ByteBuf message, Channel sendChannel, CountDownLatch receiverLatch,