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/** * Copyright (c) 2005-2010 springside.org.cn * * Licensed under the Apache License, Version 2.0 (the "License"); * * $Id: ServletUtils.java 1211 2010-09-10 16:20:45Z calvinxiu $ */ package com.dosport.system.utils; import java.io.UnsupportedEncodingException; import java.util.Enumeration; 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.springframework.util.Assert; /** * HttpServlet. * * @author calvin */ public class ServletUtils { // -- Content Type --// public static final String TEXT_TYPE = "text/plain"; public static final String JSON_TYPE = "application/json"; public static final String XML_TYPE = "text/xml"; public static final String HTML_TYPE = "text/html"; public static final String JS_TYPE = "text/javascript"; public static final String EXCEL_TYPE = "application/vnd.ms-excel"; // -- 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???. */ @SuppressWarnings("rawtypes") public static Map<String, Object> getParametersStartingWith(ServletRequest request, String prefix) { Assert.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.base64Encode(encode.getBytes()); } }