strut | An OpenAPI/Swagger manipulation library | REST library

The issue is that your beans are not even being picked up and created by the Spring Framework. Move RestweekendApplication to the package com.restweek.restweekend as follows:

ActionContext is a container placeholder for the action invocation, more detailed explanation is here.

There's a lot of reasons when an action context could be null. You are starting another thread, or modify existing one, or it's just not created yet.

To get a SessionMap there's another approach. Let your action class to implement SessionAware and make sure you have configured a default interceptor stack for the action. After that the session map should be injected to the action instance. More about it here.

You need to set the escapeHtml attribute in s:property tag to false: This should work.

Your action class should extend ActionSupport. Then you can use something like

You should reference the action to call its method in Freemarker. It is supported by the Struts 2 framework.

Simply return a json result. You should define it in the action config. I've already explained how you can return a json result without struts2-json-plugin. Now you will use it to return an JSON object to the success callback function via jQuery ajax.

First you need to add it to the project build path. Then make package of your action config to extend json-default package. It will add JSON result type to the Struts config.

Make the property noData (whatever) you want to access having getter and setter.

Add result of type JSON to the action config.

I think your question is very interesting but a little subjective..

My thought is that we must be build applications that are robust to changes, but remain pragmatic. We need to find the good point between abstraction and implementation (as described in the Clean Architecture book).

In the Java eco-system, The standard JSRs is very often defined around interfaces and not implementations, offering you a good way to avoid tight coupling to a specific framework (ex: JPA instead of Hibernate, JAX-RS instead of Jackson..).

In the Spring ecosystem, you can use these standards annotation (@Inject vs @Autowired), and it will work perfectly, but you will often loose some functionalities offered by the implementations.

Some architectures tends to separate totally the layers between your business code and the framework code (the hexagonal architecture call it the infrastructure and application layers), but it comes at a price..

The probability of this type of migration is unknown and depends on the changing needs of your project (I've never encountered a change of JPA vendor implementation). But I believe that with the most active project (Hibernate, Jackson..), you can try to reduce it.

So... Be pragmatic :)

The problem is completely unrelated to any r libraries. The reason why you only see it if you fix the r errors is that then your document is more than one page long and you actually get to see your fancy headers (the first page uses a different pagestyle, thus no error with only one page).

As the error messages says, the actual problem is that \theauthor is not defined. You manually define it for the title, you must also define it for the author.

The wrong version of jQuery framework is loaded.