Move DefaultSecureTransportParameters to separate file and add javadoc

Signed-off-by: Craig Perkins <cwperx@amazon.com>

Author: cwperks

server/src/main/java/org/opensearch/plugins/DefaultSecureTransportParameters.java

@@ -0,0 +1,28 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.plugins;
+
+import org.opensearch.common.network.NetworkModule;
+import org.opensearch.common.settings.Settings;
+
+/**
+ * Default implementation of {@link SecureTransportSettingsProvider.SecureTransportParameters}.
+ */
+class DefaultSecureTransportParameters implements SecureTransportSettingsProvider.SecureTransportParameters {
+    private final Settings settings;
+
+    DefaultSecureTransportParameters(Settings settings) {
+        this.settings = settings;
+    }
+
+    @Override
+    public boolean dualModeEnabled() {
+        return NetworkModule.TRANSPORT_SSL_DUAL_MODE_ENABLED.get(settings);
+    }
+}

server/src/main/java/org/opensearch/plugins/SecureTransportSettingsProvider.java

@@ -9,7 +9,6 @@
 package org.opensearch.plugins;
 
 import org.opensearch.common.annotation.ExperimentalApi;
-import org.opensearch.common.network.NetworkModule;
 import org.opensearch.common.settings.Settings;
 import org.opensearch.transport.Transport;
 import org.opensearch.transport.TransportAdapterProvider;
@@ -47,24 +46,14 @@ default Optional<SecureTransportParameters> parameters(Settings settings) {
         return Optional.of(new DefaultSecureTransportParameters(settings));
     }
 
+    /**
+     * Dynamic parameters that can be provided by the {@link SecureTransportSettingsProvider}
+     */
     @ExperimentalApi
     interface SecureTransportParameters {
         boolean dualModeEnabled();
     }
 
-    class DefaultSecureTransportParameters implements SecureTransportParameters {
-        private final Settings settings;
-
-        DefaultSecureTransportParameters(Settings settings) {
-            this.settings = settings;
-        }
-
-        @Override
-        public boolean dualModeEnabled() {
-            return NetworkModule.TRANSPORT_SSL_DUAL_MODE_ENABLED.get(settings);
-        }
-    }
-
     /**
      * If supported, builds the {@link TransportExceptionHandler} instance for {@link Transport} instance
      * @param settings settings