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/** * Copyright (c) 2005-2011 springside.org.cn * * Licensed under the Apache License, Version 2.0 (the "License"); * * $Id: ServletUtils.java 1595 2011-05-11 16:41:16Z calvinxiu $ */ package com.age.core.utils.web; import java.io.IOException; import java.io.UnsupportedEncodingException; import java.text.SimpleDateFormat; import java.util.Arrays; import java.util.Collections; import java.util.Date; import java.util.Enumeration; import java.util.List; import java.util.Map; import java.util.StringTokenizer; import java.util.TreeMap; import javax.servlet.ServletRequest; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.apache.commons.lang.StringUtils; import com.age.core.mapper.JsonMapper; import com.age.core.utils.AssertUtils; import com.age.core.utils.EncodeUtils; /** * HttpServlet. * * @author calvin */ public abstract class ServletUtils { //-- Content Type --// public static final String EXCEL_TYPE = "application/vnd.ms-excel"; public static final String HTML_TYPE = "text/html"; public static final String JS_TYPE = "text/javascript"; public static final String JSON_TYPE = "application/json"; public static final String XML_TYPE = "text/xml"; public static final String TEXT_TYPE = "text/plain"; //-- Header --// public static final String AUTHENTICATION_HEADER = "Authorization"; //-- --// public static final long ONE_YEAR_SECONDS = 60 * 60 * 24 * 365; /** * Header. */ public static void setExpiresHeader(HttpServletResponse response, long expiresSeconds) { //Http 1.0 header response.setDateHeader("Expires", System.currentTimeMillis() + expiresSeconds * 1000); //Http 1.1 header response.setHeader("Cache-Control", "private, max-age=" + expiresSeconds); } /** * ?Header. */ public static void setDisableCacheHeader(HttpServletResponse response) { //Http 1.0 header response.setDateHeader("Expires", 1L); response.addHeader("Pragma", "no-cache"); //Http 1.1 header response.setHeader("Cache-Control", "no-cache, no-store, max-age=0"); } /** * LastModified Header. */ public static void setLastModifiedHeader(HttpServletResponse response, long lastModifiedDate) { response.setDateHeader("Last-Modified", lastModifiedDate); } /** * Etag Header. */ public static void setEtag(HttpServletResponse response, String etag) { response.setHeader("ETag", etag); } /** * ??If-Modified-Since Header, ?. * * , checkIfModifyfalse ,304 not modify status. * * @param lastModified ?. */ public static boolean checkIfModifiedSince(HttpServletRequest request, HttpServletResponse response, long lastModified) { long ifModifiedSince = request.getDateHeader("If-Modified-Since"); if ((ifModifiedSince != -1) && (lastModified < ifModifiedSince + 1000)) { response.setStatus(HttpServletResponse.SC_NOT_MODIFIED); return false; } return true; } /** * ?? If-None-Match Header, Etag?. * * Etag, checkIfNoneMatchfalse, 304 not modify status. * * @param etag ETag. */ public static boolean checkIfNoneMatchEtag(HttpServletRequest request, HttpServletResponse response, String etag) { String headerValue = request.getHeader("If-None-Match"); if (headerValue != null) { boolean conditionSatisfied = false; if (!"*".equals(headerValue)) { StringTokenizer commaTokenizer = new StringTokenizer(headerValue, ","); while (!conditionSatisfied && commaTokenizer.hasMoreTokens()) { String currentToken = commaTokenizer.nextToken(); if (currentToken.trim().equals(etag)) { conditionSatisfied = true; } } } else { conditionSatisfied = true; } if (conditionSatisfied) { response.setStatus(HttpServletResponse.SC_NOT_MODIFIED); response.setHeader("ETag", etag); return false; } } return true; } /** * ??Header. * * @param fileName ???. */ public static void setFileDownloadHeader(HttpServletResponse response, String fileName) { try { //??? String encodedfileName = new String(fileName.getBytes(), "ISO8859-1"); response.setHeader("Content-Disposition", "attachment; filename=\"" + encodedfileName + "\""); } catch (UnsupportedEncodingException e) { } } /** * ???Request Parameters. * * Parameter???. */ public static Map<String, Object> getParametersStartingWith(ServletRequest request, String prefix) { AssertUtils.notNull(request, "Request must not be null"); Enumeration paramNames = request.getParameterNames(); Map<String, Object> params = new TreeMap<String, Object>(); if (prefix == null) { prefix = ""; } while (paramNames != null && paramNames.hasMoreElements()) { String paramName = (String) paramNames.nextElement(); if ("".equals(prefix) || paramName.startsWith(prefix)) { String unprefixed = paramName.substring(prefix.length()); String[] values = request.getParameterValues(paramName); if (values == null || values.length == 0) { // Do nothing, no values found at all. } else if (values.length > 1) { params.put(unprefixed, values); } else { params.put(unprefixed, values[0]); } } } return params; } /** * Http Basic? Header?. */ public static String encodeHttpBasic(String userName, String password) { String encode = userName + ":" + password; return "Basic " + EncodeUtils.encodeBase64(encode.getBytes()); } /** * ?json * @param response * @param object */ public static void responseJson(HttpServletResponse response, Object object) { JsonMapper jsonMapper = JsonMapper.buildNormalMapper(); String jsonStr = jsonMapper.toJson(object); try { response.setContentType("text/plain"); response.getWriter().write(jsonStr); response.getWriter().flush(); response.getWriter().close(); } catch (IOException e) { } } /** * ? * @param response * @param object */ public static void responseText(HttpServletResponse response, String text) { try { response.getWriter().write(text); response.getWriter().flush(); response.getWriter().close(); } catch (IOException e) { } } /** * ?xml? * @param response * @param object */ public static void responseXml(HttpServletResponse response, String xml) { try { response.setContentType("text/xml"); response.getWriter().write(xml); response.getWriter().flush(); response.getWriter().close(); } catch (IOException e) { } } public static String getStringParameter(HttpServletRequest request, String name) { return request.getParameter(name); } public static Integer getIntegerParameter(HttpServletRequest request, String name) { String value = getStringParameter(request, name); if (StringUtils.isNumeric(value)) return new Integer(value); else return null; } public static Boolean getBooleanParameter(HttpServletRequest request, String name) { String value = getStringParameter(request, name); if (StringUtils.isNotBlank(value)) return Boolean.parseBoolean(value); else return Boolean.FALSE; } public static Date getDateTimeParameter(HttpServletRequest request, String name) { String value = getStringParameter(request, name); try { if (StringUtils.isNotBlank(value)) return new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").parse(value); } catch (Exception e) { e.printStackTrace(); } return null; } public static Date getDateParameter(HttpServletRequest request, String name) { String value = getStringParameter(request, name); try { if (StringUtils.isNotBlank(value)) return new SimpleDateFormat("yyyy-MM-dd").parse(value); } catch (Exception e) { e.printStackTrace(); } return null; } /** * ?Request Parameter. */ @SuppressWarnings("unchecked") public static List<String> getListParameter(HttpServletRequest request, String name) { String[] values = request.getParameterValues(name); return values == null ? Collections.EMPTY_LIST : Arrays.asList(values); } }