Including a JSP into a sling servlet

aem, osgi, sling

Solution

Including scripts

Use following construction to include script `/apps/test.jsp` inside the servlet and pass some values (bindings) to it:

@Reference
private ServletResolver servletResolver;

public void doGet(SlingHttpServletRequest request, SlingHttpServletResponse response) throws ServletException, IOException {
    Servlet servlet = servletResolver.resolveServlet(request.getResource(), "/apps/test.jsp");
    request.setAttribute("sampleBinding", "bindingValue");
    servlet.service(request, response);
}

The script itself may look like this:

<%@page session="false" contentType="text/html; charset=utf-8"
%><%@include file="/libs/foundation/global.jsp"%>

Binding value: ${sampleBinding}

Using models

You may also consider a second approach - don't create servlet for each component, but stick to JSP and at the beginning of each script create a model object. Sample script:

<%@page session="false" contentType="text/html; charset=utf-8"
%><%@include file="/libs/foundation/global.jsp"%><%
  pageContext.setAttribute("model", new MyModel(slingRequest, slingResponse));
%>

Value from model: ${model.value}

And sample model:

public class MyModel {

    private final SlingHttpServletRequest request;

    private final SlingHttpServletResponse response;

    public MyModel(SlingHttpServletRequest request, SlingHttpServletResponse response) {
        this.request = request;
        this.response = response;
    }

    public String getValue() {
        // you may use request & response objects here
        return "sample value";
    }
}

If you like this approach, you may use a framework that makes writing such models easier. Two interesting solutions are:

- Sling models

- Slice

Problem

Original source