Struts2Utils.java

package com.norteksoft.acs.base.web.struts2;

import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;
import java.util.Locale;
import java.util.Map;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import org.apache.commons.lang.StringUtils;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.struts2.ServletActionContext;

import com.norteksoft.product.util.JsonParser;
import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.LocaleProvider;
import com.opensymphony.xwork2.TextProvider;
import com.opensymphony.xwork2.TextProviderFactory;

/**
 * Struts2 Utils类.
 * 
 * 实现获取Request/Response/Session与绕过jsp/freemaker直接输出文本的简化函数.
 * 
 */
public class Struts2Utils {

	//header 常量定义
	private static final String ENCODING_PREFIX = "encoding";
	private static final String NOCACHE_PREFIX = "no-cache";
	private static final String ENCODING_DEFAULT = "UTF-8";
	private static final boolean NOCACHE_DEFAULT = true;

	private static Log logger = LogFactory.getLog(Struts2Utils.class);

	// 取得Request/Response/Session的简化函数 //

	/**
	 * 取得HttpSession的简化方法.
	 */
	public static HttpSession getSession() {
		return ServletActionContext.getRequest().getSession();
	}

	/**
	 * 取得HttpRequest的简化方法.
	 */
	public static HttpServletRequest getRequest() {
		return ServletActionContext.getRequest();
	}

	/**
	 * 取得HttpResponse的简化方法.
	 */
	public static HttpServletResponse getResponse() {
		return ServletActionContext.getResponse();
	}

	/**
	 * 取得Request Parameter的简化方法.
	 */
	public static String getParameter(String name) {
		return getRequest().getParameter(name);
	}

	// 绕过jsp/freemaker直接输出文本的函数 //

	/**
	 * 直接输出内容的简便函数.

	 * 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 可变的header数组，目前接受的值为"encoding:"或"no-cache:",默认值分别为UTF-8和true.
	 */
	public static void render(final String contentType, final String content, final String... headers) {
		try {
			//分析headers参数
			String encoding = ENCODING_DEFAULT;
			boolean noCache = NOCACHE_DEFAULT;
			for (String header : headers) {
				String headerName = StringUtils.substringBefore(header, ":");
				String headerValue = StringUtils.substringAfter(header, ":");

				if (StringUtils.equalsIgnoreCase(headerName, ENCODING_PREFIX)) {
					encoding = headerValue;
				} else if (StringUtils.equalsIgnoreCase(headerName, NOCACHE_PREFIX)) {
					noCache = Boolean.parseBoolean(headerValue);
				} else
					throw new IllegalArgumentException(headerName + "不是一个合法的header类型");
			}

			HttpServletResponse response = ServletActionContext.getResponse();

			//设置headers参数
			String fullContentType = contentType + ";charset=" + encoding;
			response.setContentType(fullContentType);
			if (noCache) {
				response.setHeader("Pragma", "No-cache");
				response.setHeader("Cache-Control", "no-cache");
				response.setDateHeader("Expires", 0);
			}

			response.getWriter().write(content);
			response.getWriter().flush();

		} catch (IOException e) {
			logger.error(e.getMessage(), e);
		}
	}

	/**
	 * 直接输出文本.
	 * @see #render(String, String, String...)
	 */
	public static void renderText(final String text, final String... headers) {
		render("text/plain", text, headers);
	}

	/**
	 * 直接输出HTML.
	 * @see #render(String, String, String...)
	 */
	public static void renderHtml(final String html, final String... headers) {
		render("text/html", html, headers);
	}

	/**
	 * 直接输出XML.
	 * @see #render(String, String, String...)
	 */
	public static void renderXml(final String xml, final String... headers) {
		render("text/xml", xml, headers);
	}

	/**
	 * 直接输出JSON.
	 * 
	 * @param string json字符串.
	 * @see #render(String, String, String...)
	 */
	public static void renderJson(final String string, final String... headers) {
		render("application/json", string, headers);
	}

	/**
	 * 直接输出JSON.
	 * 
	 * @param map Map对象,将被转化为json字符串.
	 * @see #render(String, String, String...)
	 */
	@SuppressWarnings("unchecked")
	public static void renderJson(final Map map, final String... headers) {
		String jsonString = JsonParser.object2Json(map);
		renderJson(jsonString, headers);
	}

	/**
	 * 直接输出JSON.
	 * 
	 * @param object Java对象,将被转化为json字符串.
	 * @see #render(String, String, String...)
	 */
	public static void renderJson(final Object object, final String... headers) {
		String jsonString = JsonParser.object2Json(object);
		renderJson(jsonString, headers);
	}
	
	public static TextProvider getTextProvider(){
		return textProvider;
	}
	
	public static void resetExportExcelProp(String fileName){
		getResponse().reset();
//		try {
//			fileName = URLEncoder.encode(new String(fileName.getBytes("UTF-8"), "UTF-8"), "UTF-8");
//		} catch (UnsupportedEncodingException e) {
//			logger.error("导出文件名编码转换错误", e);
//		}
		try {
			byte[] byname = fileName.getBytes("gbk");
			fileName = new String(byname,"8859_1");
		} catch (IOException e) {
			e.printStackTrace();
		}
		getResponse().setContentType("application/vnd.ms-excel;charset=UTF-8");
		getResponse().setHeader("Content-Disposition", "attachment;filename=\"" + fileName + ".xls\"");
		getResponse().setHeader("Cache-Control", "must-revalidate, post-check=0, pre-check=0");
		getResponse().setHeader("Pragma", "public");
		getResponse().setDateHeader("Expires", (System.currentTimeMillis() + 1000));
}
	
	private final static transient TextProvider textProvider = 
		new TextProviderFactory().createInstance(Struts2Utils.class, new LocaleProvider(){
			public Locale getLocale() {
		        ActionContext ctx = ActionContext.getContext();
		        if (ctx != null) {
		            return ctx.getLocale();
		        } else {
		        	logger.debug("Action context not initialized");
		            return null;
		        }
		    }});
}