org.seasar.s2click.servlet.S2ClickServlet.java Source code

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Here is the source code for org.seasar.s2click.servlet.S2ClickServlet.java

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/*
 * Copyright 2006-2011 the Seasar Foundation and the Others.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
 * either express or implied. See the License for the specific language
 * governing permissions and limitations under the License.
 */
package org.seasar.s2click.servlet;

import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.lang.reflect.Method;

import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import net.arnx.jsonic.JSON;
import ognl.OgnlException;
import ognl.TypeConverter;

import org.apache.click.ClickServlet;
import org.apache.click.Context;
import org.apache.click.Page;
import org.apache.click.util.ErrorPage;
import org.apache.commons.io.IOUtils;
import org.apache.commons.lang.StringUtils;
import org.seasar.framework.container.S2Container;
import org.seasar.framework.container.factory.SingletonS2ContainerFactory;
import org.seasar.framework.container.util.SmartDeployUtil;
import org.seasar.s2click.S2ClickPage;
import org.seasar.s2click.annotation.Ajax;
import org.seasar.s2click.exception.AjaxException;
import org.seasar.s2click.filter.UrlPatternFilter;
import org.seasar.s2click.util.AjaxUtils;

/**
 * Seasar2?Click Framework??????
 *
 * @author Naoki Takezoe
 */
public class S2ClickServlet extends ClickServlet {

    private static final long serialVersionUID = 1L;
    private boolean initialized = false;

    /**
     * HOT deploy?????????Click Framework?????
     */
    @Override
    public void init() throws ServletException {
        S2Container container = SingletonS2ContainerFactory.getContainer();
        if (!SmartDeployUtil.isHotdeployMode(container)) {
            super.init();
            initialized = true;
        }
    }

    /**
     * HOT deploy????Click Framework?????
     */
    @Override
    public void service(ServletRequest req, ServletResponse res) throws ServletException, IOException {

        String hotDeployInitStatus = (String) req.getAttribute(UrlPatternFilter.HOTDEPLOY_INIT_KEY);

        if (initialized == false && !"initialized".equals(hotDeployInitStatus)) {
            super.init();
            req.setAttribute(UrlPatternFilter.HOTDEPLOY_INIT_KEY, "initialized");

            if ("initialize".equals(hotDeployInitStatus)) {
                return;
            }
        }

        super.service(new S2ClickRequestWrapper((HttpServletRequest) req), res);
    }

    /**
     * S2Container??????
     */
    @Override
    @SuppressWarnings("rawtypes")
    protected Page newPageInstance(String path, Class pageClass, HttpServletRequest request) throws Exception {
        if (pageClass == Page.class || pageClass == ErrorPage.class) {
            return (Page) pageClass.newInstance();
        }
        S2Container container = SingletonS2ContainerFactory.getContainer();
        return (Page) container.getComponent(pageClass);
    }

    /**
     * ??????{@link S2ClickPage}?????
     * ???????
     */
    @Override
    protected void processPageRequestParams(Page page) throws OgnlException {
        // ?????
    }

    @Override
    protected void renderTemplate(Page page) throws Exception {
        String skipRendering = (String) page.getContext().getRequestAttribute(S2ClickPage.SKIP_RENDERING);
        if (!"true".equals(skipRendering)) {
            super.renderTemplate(page);
        }
    }

    protected void processPage(Page page) throws Exception {

        final Context context = page.getContext();
        final HttpServletRequest request = context.getRequest();

        String methodName = request.getParameter("ajax");
        if (StringUtils.isNotEmpty(methodName)) {
            // Ajax???
            Method method = getAjaxMethod(page, methodName);
            if (method != null) {
                // ?
                Class<?>[] types = method.getParameterTypes();
                Object[] args = new Object[method.getParameterTypes().length];
                TypeConverter converter = getTypeConverter();
                for (int i = 0; i < args.length; i++) {
                    args[i] = converter.convertValue(null, null, null, null, request.getParameter("arg" + i),
                            types[i]);
                }

                // ??
                Object result = method.invoke(page, (Object[]) args);

                if (result != null) {
                    renderAjaxResponse(context, result);
                }

            } else {
                throw new AjaxException(
                        "Ajax??????????: " + methodName);
            }

        } else {
            // ???
            super.processPage(page);
        }
    }

    /**
     * {@link Ajax}??????????
     * <p>
     * ?String?????????????<code>"text/html; charset=utf-8"</code>????
     * String???JSON?????????<code>"application/x-javascript; charset=utf-8"</code>????
     * <p>
     * ????????????????
     *
     * @param context 
     * @param result Ajax?????
     * @throws Exception ?????
     */
    protected void renderAjaxResponse(Context context, Object result) throws Exception {

        final HttpServletResponse response = context.getResponse();

        // ???
        OutputStream out = null;
        InputStream in = null;

        try {
            if (result instanceof String) {
                // ???HTML????
                in = new ByteArrayInputStream(((String) result).getBytes("UTF-8"));
                response.setContentType(AjaxUtils.CONTENT_TYPE_HTML);

            } else {
                // ?????JSON????
                String json = JSON.encode(result);
                in = new ByteArrayInputStream(json.getBytes("UTF-8"));
                response.setContentType(AjaxUtils.CONTENT_TYPE_JSON);
            }

            response.setContentLength(in.available());
            out = response.getOutputStream();
            IOUtils.copy(in, out);
            response.flushBuffer();

        } finally {
            IOUtils.closeQuietly(out);
            IOUtils.closeQuietly(in);
        }
    }

    /**
     * ?Ajax???????
     *
     * @param page ?
     * @param methodName Ajax?????
     * @return {@link Ajax}?????????public????
     *   ???????<code>null</code>???
     */
    protected Method getAjaxMethod(Page page, String methodName) {
        Method[] methods = page.getClass().getMethods();
        for (Method method : methods) {
            if (method.getName().equals(methodName) && method.getAnnotation(Ajax.class) != null) {
                return method;
            }
        }
        return null;
    }

}