Java tutorial
/** * Copyright (c)2010-2011 Enterprise Website Content Management System(EWCMS), All rights reserved. * EWCMS PROPRIETARY/CONFIDENTIAL. Use is subject to license terms. * http://www.ewcms.com */ package com.ewcms.component.util; import java.io.IOException; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import javax.servlet.http.HttpSession; import org.apache.commons.lang.StringUtils; import org.apache.struts2.ServletActionContext; /** * Struts2. * * ?Request/Response/Sessionjsp/freemaker. * * @author calvin */ public class Struts2Util { //-- header ? --// private static final String HEADER_ENCODING = "encoding"; private static final String HEADER_NOCACHE = "no-cache"; private static final String DEFAULT_ENCODING = "UTF-8"; private static final boolean DEFAULT_NOCACHE = true; //-- ?Request/Response/Session --// /** * ?HttpSession. */ public static HttpSession getSession() { return ServletActionContext.getRequest().getSession(); } /** * ?HttpSession. */ public static HttpSession getSession(boolean isNew) { return ServletActionContext.getRequest().getSession(isNew); } /** * ?HttpSessionAttribute. */ public static Object getSessionAttribute(String name) { HttpSession session = getSession(false); return (session != null ? session.getAttribute(name) : null); } /** * ?HttpRequest. */ public static HttpServletRequest getRequest() { return ServletActionContext.getRequest(); } /** * ?HttpRequestParameter. */ public static String getParameter(String name) { return getRequest().getParameter(name); } /** * ?HttpResponse. */ public static HttpServletResponse getResponse() { return ServletActionContext.getResponse(); } //-- jsp/freemaker --// /** * . * eg. * render("text/plain", "hello", "encoding:GBK"); * render("text/plain", "hello", "no-cache:false"); * render("text/plain", "hello", "encoding:GBK", "no-cache:false"); * * @param headers ??header??"encoding:""no-cache:",UTF-8true. */ public static void render(final String contentType, final String content, final String... headers) { HttpServletResponse response = initResponseHeader(contentType, headers); try { response.getWriter().write(content); response.getWriter().flush(); } catch (IOException e) { throw new RuntimeException(e.getMessage(), e); } } /** * . * @see #render(String, String, String...) */ public static void renderText(final String text, final String... headers) { render(ServletUtil.TEXT_TYPE, text, headers); } /** * HTML. * @see #render(String, String, String...) */ public static void renderHtml(final String html, final String... headers) { render(ServletUtil.HTML_TYPE, html, headers); } /** * XML. * @see #render(String, String, String...) */ public static void renderXml(final String xml, final String... headers) { render(ServletUtil.XML_TYPE, xml, headers); } /** * JSON. * * @param jsonString json. * @see #render(String, String, String...) */ public static void renderJson(final String jsonString, final String... headers) { render(ServletUtil.JSON_TYPE, jsonString, headers); } /** * ?MashupJSONP. * * @param callbackName callback??. * @param object Java,?List<POJO>, POJO[], POJO ,?Map??, json. */ public static void renderJsonp(final String callbackName, final String jsonString, final String... headers) { String result = new StringBuilder().append(callbackName).append("(").append(jsonString).append(");") .toString(); render(ServletUtil.JS_TYPE, result, headers); } /** * ?contentTypeheaders. */ private static HttpServletResponse initResponseHeader(final String contentType, final String... headers) { //?headers? String encoding = DEFAULT_ENCODING; boolean noCache = DEFAULT_NOCACHE; for (String header : headers) { String headerName = StringUtils.substringBefore(header, ":"); String headerValue = StringUtils.substringAfter(header, ":"); if (StringUtils.equalsIgnoreCase(headerName, HEADER_ENCODING)) { encoding = headerValue; } else if (StringUtils.equalsIgnoreCase(headerName, HEADER_NOCACHE)) { noCache = Boolean.parseBoolean(headerValue); } else { throw new IllegalArgumentException(headerName + "??header"); } } HttpServletResponse response = ServletActionContext.getResponse(); //headers? String fullContentType = contentType + ";charset=" + encoding; response.setContentType(fullContentType); if (noCache) { ServletUtil.setNoCacheHeader(response); } return response; } public static String getIp() { return ServletActionContext.getRequest().getRemoteAddr(); } }