MockServletInvocationTest.java

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 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
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package org.apache.wink.server.internal.servlet;

import java.io.IOException;
import java.util.HashSet;
import java.util.LinkedHashSet;
import java.util.Set;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.ws.rs.core.Application;

import junit.framework.TestCase;

import org.springframework.mock.web.MockHttpServletRequest;
import org.springframework.mock.web.MockHttpServletResponse;
import org.springframework.mock.web.MockServletConfig;

/**
 * <p>
 * The unit tests should extend this class in order to simulate the servlet
 * invocation.
 * <p>
 * The method <tt>invoke</tt> invokes the servlet call.
 */
public abstract class MockServletInvocationTest extends TestCase {

    private static ThreadLocal<MockServletInvocationTest> tls =
                                                                  new ThreadLocal<MockServletInvocationTest>();
    private HttpServlet                                   servlet;

    public static class MockApplication extends Application {

        @Override
        public Set<Class<?>> getClasses() {
            HashSet<Class<?>> set = new LinkedHashSet<Class<?>>();
            for (Class<?> cls : tls.get().getClasses()) {
                set.add(cls);
            }
            return set;
        }

        @Override
        public Set<Object> getSingletons() {
            HashSet<Object> set = new LinkedHashSet<Object>();
            for (Object o : tls.get().getSingletons()) {
                set.add(o);
            }
            return set;
        }

    }

    /**
     * Returns the class name of an application class. Override this method in
     * order to provide a custom Application class. Pay attention that when
     * overridden, the methods getClasses() and getSingletons() will be ignored.
     */
    protected String getApplicationClassName() {
        return MockApplication.class.getName();
    }

    @Override
    protected void setUp() throws Exception {
        super.setUp();

        servlet =
            (HttpServlet)Class.forName("org.apache.wink.server.internal.servlet.RestServlet")
                .newInstance();
        MockServletConfig servletConfig = new MockServletConfig();
        servletConfig.addInitParameter("javax.ws.rs.Application", getApplicationClassName());

        String propertiesFile = getPropertiesFile();
        if (propertiesFile != null) {
            servletConfig.addInitParameter("propertiesLocation", propertiesFile);
        }

        String deploymentConfigClass = getDeploymentConfigurationClassName();
        if (deploymentConfigClass != null) {
            servletConfig.addInitParameter("deploymentConfiguration", deploymentConfigClass);
        }

        tls.set(this);
        servlet.init(servletConfig);
    }

    /**
     * @return the value of the deploymentConfiguration parameter. The class
     *         name must be a name of a DeploymentConfiguration class on the
     *         classpath.
     */
    protected String getDeploymentConfigurationClassName() {
        return null;
    }

    /**
     * @return the name of the properties file. The file must be located on the
     *         classpath. By default returns null.
     */
    protected String getPropertiesFile() {
        return null;
    }

    /**
     * @return the classes of JAX-RS that will be returned by the
     *         Application.getClasses()
     */
    protected Class<?>[] getClasses() {
        return new Class<?>[0];
    }

    /**
     * @return the singletons of JAX-RS that will be returned by the
     *         Application.getSingletons
     */
    protected Object[] getSingletons() {
        return new Object[0];
    }

    /**
     * Passes the test to the servlet instance simulating AS behaviour.
     * 
     * @param request the filled request
     * @return a new response as filled by the servlet
     * @throws IOException
     * @throws ServletException
     */
    public MockHttpServletResponse invoke(MockHttpServletRequest request) throws ServletException,
        IOException {
        MockHttpServletResponse response = new MockHttpServletResponse();

        servlet.service(request, response);

        return response;
    }

    /**
     * Return the servlet object. Users of MockServletInvocationTest do not need
     * to manipulate the servlet object directly. This method is intended to
     * allow users to inspect the servlet if their test class needs to do so.
     * 
     * @return the HttpServlet object
     */
    public HttpServlet getServlet() {
        return servlet;
    }

}