Sonar fixes

- a few complexities
- final method calls from ctor
- raw exception throwing
- useless overrides
- loss of stack trace

spring-integration-ip/src/main/java/org/springframework/integration/ip/tcp/connection/FailoverClientConnectionFactory.java

@@ -80,7 +80,7 @@ public class FailoverClientConnectionFactory extends AbstractClientConnectionFac
 	 * the real listener supplied here, with the modified message.
 	 */
 	@Override
-	public void registerListener(TcpListener listener) {
+	public void registerListener(TcpListener listener) { // NOSONAR - not useless, custom Javadoc
 		super.registerListener(listener);
 	}
 

spring-integration-ip/src/main/java/org/springframework/integration/ip/tcp/connection/TcpConnectionSupport.java

@@ -138,7 +138,7 @@ public abstract class TcpConnectionSupport implements TcpConnection {
 			this.connectionFactoryName = connectionFactoryName;
 		}
 		if (this.logger.isDebugEnabled()) {
-			this.logger.debug("New connection " + this.getConnectionId());
+			this.logger.debug("New connection " + this.connectionId);
 		}
 	}
 

spring-integration-ip/src/main/java/org/springframework/integration/ip/tcp/connection/TcpNioConnection.java

@@ -358,9 +358,9 @@ public class TcpNioConnection extends TcpConnectionSupport {
 					throw new IOException("Timed out waiting for IO");
 				}
 			}
-			catch (@SuppressWarnings(UNUSED) InterruptedException e) {
+			catch (InterruptedException e) {
 				Thread.currentThread().interrupt();
-				throw new IOException("Interrupted waiting for IO");
+				throw new IOException("Interrupted waiting for IO", e);
 			}
 		}
 		Message<?> message = null;

spring-integration-ip/src/main/java/org/springframework/integration/ip/tcp/connection/TcpNioSSLConnection.java

@@ -421,7 +421,7 @@ public class TcpNioSSLConnection extends TcpNioConnection {
 			}
 			catch (InterruptedException e) {
 				Thread.currentThread().interrupt();
-				throw new MessagingException("Interrupted during SSL Handshaking");
+				throw new MessagingException("Interrupted during SSL Handshaking", e);
 			}
 		}