Merge pull request #2948 from oah1021/getSignature

Removed unnecessary judgments

Author: hazendaz

src/main/java/org/apache/ibatis/reflection/Reflector.java

@@ -323,9 +323,7 @@ private void addUniqueMethods(Map<String, Method> uniqueMethods, Method[] method
   private String getSignature(Method method) {
     StringBuilder sb = new StringBuilder();
     Class<?> returnType = method.getReturnType();
-    if (returnType != null) {
-      sb.append(returnType.getName()).append('#');
-    }
+    sb.append(returnType.getName()).append('#');
     sb.append(method.getName());
     Class<?>[] parameters = method.getParameterTypes();
     for (int i = 0; i < parameters.length; i++) {