actionresponseimpl.java

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/*
 * @author <a href="mailto:[e-mail]">Jason Novotny</a>
 * @version $Id: ActionResponseImpl.java 4889 2006-06-28 18:36:43Z novotny $
 */
package org.gridsphere.portlet.impl;

import javax.portlet.*;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.util.*;


/**
 * The <CODE>ActionResponse</CODE> interface represents the portlet
 * response to an action request.
 * It extends the <CODE>PortletResponse</CODE> interface to provide specific
 * action response functionality to portlets.<br>
 * The portlet container creates an <CODE>ActionResponse</CODE> object and
 * passes it as argument to the portlet's <CODE>processAction</CODE> method.
 *
 * @see ActionRequest
 * @see PortletResponse
 */
public class ActionResponseImpl extends PortletResponseImpl implements ActionResponse {

    /**
     * Is it still allowed to invoke the method sendRedirect() ?
     */
    boolean isRedirectAllowed = true;

    private boolean redirected = false;
    private String redirectLocation = null;
    protected Map<String, String[]> renderParams = null;

    /**
     * Constructs an instance of SportletResponse using an
     * <code>HttpServletResponse</code> as a proxy
     *
     * @param req the <code>HttpServletRequest</code>
     * @param res the <code>HttpServletResponse</code>
     */
    public ActionResponseImpl(HttpServletRequest req, HttpServletResponse res) {
        super(req, res);
        renderParams = new HashMap<String, String[]>();
    }

    /**
     * Sets the window state of a portlet to the given window state.
     * <p/>
     * Possible values are the standard window states and any custom
     * window states supported by the portal and the portlet.
     * Standard window states are:
     * <ul>
     * <li>MINIMIZED
     * <li>NORMAL
     * <li>MAXIMIZED
     * </ul>
     *
     * @param windowState the new portlet window state
     * @throws WindowStateException  if the portlet cannot switch to the specified window state.
     *                               To avoid this exception the portlet can check the allowed
     *                               window states with <code>Request.isWindowStateAllowed()</code>.
     * @throws IllegalStateException if the method is invoked after <code>sendRedirect</code> has been called.
     * @see WindowState
     */
    public void setWindowState(WindowState windowState)
            throws WindowStateException, IllegalStateException {
        if (redirected) {
            throw new IllegalStateException("cannot invoke setWindowState after sendRedirect has been called");
        }
        PortalContext portalContext = (PortalContext)req.getAttribute(SportletProperties.PORTAL_CONTEXT);
        if (portalContext != null) {
            Enumeration e = portalContext.getSupportedWindowStates();
            boolean found = false;
            while (e.hasMoreElements() && (!found)) {
                WindowState s = (WindowState) e.nextElement();
                if (s.toString().equalsIgnoreCase(windowState.toString())) {
                    found = true;
                }
            }
            if (!found) throw new WindowStateException("Unsupported window state!", windowState);
        } else {
            throw new IllegalStateException("No PortalContext found!");
        }

        isRedirectAllowed = false;

        req.setAttribute(SportletProperties.PORTLET_WINDOW, windowState);
    }

    /**
     * Sets the portlet mode of a portlet to the given portlet mode.
     * <p/>
     * Possible values are the standard portlet modes and any custom
     * portlet modes supported by the portal and the portlet. Portlets
     * must declare in the deployment descriptor the portlet modes they
     * support for each markup type.
     * Standard portlet modes are:
     * <ul>
     * <li>EDIT
     * <li>HELP
     * <li>VIEW
     * </ul>
     * <p/>
     * Note: The portlet may still be called in a different window
     * state in the next render call, depending on the portlet container / portal.
     *
     * @param portletMode the new portlet mode
     * @throws PortletModeException  if the portlet cannot switch to this portlet mode,
     *                               because the portlet or portal does not support it for this markup,
     *                               or the current user is not allowed to switch to this portlet mode.
     *                               To avoid this exception the portlet can check the allowed
     *                               portlet modes with <code>Request.isPortletModeAllowed()</code>.
     * @throws IllegalStateException if the method is invoked after <code>sendRedirect</code> has been called.
     */
    public void setPortletMode(PortletMode portletMode)
            throws PortletModeException {

        if (redirected) {
            throw new IllegalStateException("it is not allowed to invoke setPortletMode after sendRedirect has been called");
        }
        Set allowedModes = (Set) req.getAttribute(SportletProperties.ALLOWED_MODES);
        if (allowedModes != null) {
            if (!allowedModes.contains(portletMode.toString())) throw new PortletModeException("Unsupported portlet mode!", portletMode);
            req.setAttribute(SportletProperties.PORTLET_MODE, portletMode);
        } else {
            throw new IllegalStateException("No list of supported modes has been provided!");
        }
        isRedirectAllowed = false;
    }

    /**
     * Instructs the portlet container to send a redirect response
     * to the client using the specified redirect location URL.
     * <p/>
     * This method only accepts an absolute URL (e.g.
     * <code>http://my.co/myportal/mywebap/myfolder/myresource.gif</code>)
     * or a full path URI (e.g. <code>/myportal/mywebap/myfolder/myresource.gif</code>).
     * If required,
     * the portlet container may encode the given URL before the
     * redirection is issued to the client.
     * <p/>
     * The sendRedirect method can not be invoked after any of the
     * following methods of the ActionResponse interface has been called:
     * <ul>
     * <li>setPortletMode
     * <li>setWindowState
     * <li>setRenderParameter
     * <li>setRenderParameters
     * </ul>
     *
     * @throws IllegalStateException if the method is invoked after any of above mentioned methods of
     *                               the ActionResponse interface has been called.
     * @param		location	the redirect location URL
     * @exception	java.io.IOException if an input or output exception occurs.
     * @exception	IllegalArgumentException if a relative path URL is given
     */
    public void sendRedirect(String location)
            throws java.io.IOException {
        // TODO needs work
        if (isRedirectAllowed) {
            if (location != null) {
                HttpServletResponse res = (HttpServletResponse) super.getResponse();
                if (location.indexOf("/") == -1) throw new IllegalArgumentException("Must be an absolute URL or full path URI");
                if (location.indexOf("://") != -1) {
                    //   provider.setAbsoluteURL(location);
                } else {
                    //   provider.setFullPath(location);
                }
                location = res.encodeRedirectURL(location.toString());
                redirectLocation = location;
                redirected = true;
                req.setAttribute(SportletProperties.RESPONSE_COMMITTED, "true");
                // Don't do actual redirect this will be done by PortletServlet
                // res.sendRedirect(location);
            }
        } else {
            throw new IllegalStateException("Can't invoke sendRedirect() after certain methods have been called");
        }
    }

    /**
     * Sets a parameter map for the render request.
     * <p/>
     * All previously set render parameters are cleared.
     * <p/>
     * These parameters will be accessible in all
     * sub-sequent render calls via the
     * <code>PortletRequest.getParameter</code> call until
     * a new request is targeted to the portlet.
     * <p/>
     * The given parameters do not need to be encoded
     * prior to calling this method.
     *
     * @param parameters Map containing parameter names for
     *                   the render phase as
     *                   keys and parameter values as map
     *                   values. The keys in the parameter
     *                   map must be of type String. The values
     *                   in the parameter map must be of type
     *                   String array (<code>String[]</code>).
     * @throws IllegalStateException if the method is invoked after <code>sendRedirect</code> has been called.
     * @exception	IllegalArgumentException if parameters is <code>null</code>, if
     * any of the key/values in the Map are <code>null</code>,
     * if any of the keys is not a String, or if any of
     * the values is not a String array.
     */
    public void setRenderParameters(java.util.Map parameters) {
        if (redirected) {
            throw new IllegalStateException("Can't invoke setRenderParameters() after sendRedirect() has been called");
        }
        if (parameters == null) {
            throw new IllegalArgumentException("Render parameters must not be null.");
        }
        Map<String, String[]> params = new HashMap<String, String[]>();
        for (Object obj : parameters.keySet()) {
            if (!(obj instanceof String))
                throw new IllegalArgumentException("Key must not be null and of type java.lang.String.");
            String key = (String) obj;

            Object vals = parameters.get(key);

            if (!(vals instanceof String[]))
                throw new IllegalArgumentException("Value must not be null and of type java.lang.String[].");
            String newkey = SportletProperties.RENDER_PARAM_PREFIX + key;
            params.put(newkey, (String[])vals);
        }
        renderParams.clear();
        renderParams.putAll(params);
        isRedirectAllowed = false;
    }


    /**
     * Sets a String parameter for the render request.
     * <p/>
     * These parameters will be accessible in all
     * sub-sequent render calls via the
     * <code>PortletRequest.getParameter</code> call until
     * a request is targeted to the portlet.
     * <p/>
     * This method replaces all parameters with the given key.
     * <p/>
     * The given parameter do not need to be encoded
     * prior to calling this method.
     *
     * @param key   key of the render parameter
     * @param value value of the render parameter
     * @throws IllegalStateException if the method is invoked after <code>sendRedirect</code> has been called.
     * @exception IllegalArgumentException if key or value are <code>null</code>.
     */
    public void setRenderParameter(String key, String value) {
        if (redirected) {
            throw new IllegalStateException("Can't invoke setRenderParameter() after sendRedirect() has been called");
        }
        if ((key == null) || (value == null)) {
            throw new IllegalArgumentException("Render parameter key or value must not be null.");
        }
        renderParams.put(SportletProperties.RENDER_PARAM_PREFIX + key, new String[]{value});
        isRedirectAllowed = false;
    }

    /**
     * Sets a String array parameter for the render request.
     * <p/>
     * These parameters will be accessible in all
     * sub-sequent render calls via the
     * <code>PortletRequest.getParameter</code> call until
     * a request is targeted to the portlet.
     * <p/>
     * This method replaces all parameters with the given key.
     * <p/>
     * The given parameter do not need to be encoded
     * prior to calling this method.
     *
     * @param key    key of the render parameter
     * @param values values of the render parameter
     * @throws IllegalStateException if the method is invoked after <code>sendRedirect</code> has been called.
     * @exception	IllegalArgumentException if key or value are <code>null</code>.
     */
    public void setRenderParameter(String key, String[] values) {
        if (redirected) {
            throw new IllegalStateException("Can't invoke setRenderParameter() after sendRedirect() has been called");
        }
        if (key == null || values == null || values.length == 0) {
            throw new IllegalArgumentException("Render parameter key or value  must not be null or values be an empty array.");
        }
        renderParams.put(SportletProperties.RENDER_PARAM_PREFIX + key, values);
        isRedirectAllowed = false;
    }

    public Map getRenderParameters() {
        return renderParams;
    }

    public String getRedirectLocation() {
        return redirectLocation;
    }

}