com.yiji.openapi.sdk.util.Servlets.java Source code

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Here is the source code for com.yiji.openapi.sdk.util.Servlets.java

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/**
 * Copyright (c) 2005-2012 springside.org.cn
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 */
package com.yiji.openapi.sdk.util;

import com.google.common.collect.Lists;
import com.google.common.collect.Maps;
import com.google.common.net.HttpHeaders;
import org.apache.commons.io.IOUtils;
import org.apache.commons.lang3.StringUtils;
import org.apache.commons.lang3.Validate;
import org.springframework.http.MediaType;

import javax.servlet.ServletRequest;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.ByteArrayInputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.UnsupportedEncodingException;
import java.nio.charset.Charset;
import java.util.*;
import java.util.Map.Entry;

/**
 * HttpServlet.
 * 
 */
public class Servlets {

    // --  --//
    public static final long ONE_YEAR_SECONDS = 60 * 60 * 24 * 365;

    public static void writeResponse(HttpServletResponse response, String data) {
        OutputStream output = null;
        InputStream input = null;
        try {
            response.setCharacterEncoding("UTF-8");
            response.setContentType(MediaType.APPLICATION_JSON_VALUE);
            output = response.getOutputStream();
            input = new ByteArrayInputStream(data.getBytes(Charset.forName("UTF-8")));
            IOUtils.copy(input, output);
            output.flush();
        } catch (Exception e) {
            throw new RuntimeException("?(flushResponse):" + e.getMessage());
        } finally {
            IOUtils.closeQuietly(output);
            IOUtils.closeQuietly(input);
        }
    }

    /**
     *  Header.
     */
    public static void setExpiresHeader(HttpServletResponse response, long expiresSeconds) {
        // Http 1.0 header, set a fix expires date.
        response.setDateHeader(HttpHeaders.EXPIRES, System.currentTimeMillis() + expiresSeconds * 1000);
        // Http 1.1 header, set a time after now.
        response.setHeader(HttpHeaders.CACHE_CONTROL, "private, max-age=" + expiresSeconds);
    }

    /**
     * ?Header.
     */
    public static void setNoCacheHeader(HttpServletResponse response) {
        // Http 1.0 header
        response.setDateHeader(HttpHeaders.EXPIRES, 1L);
        response.addHeader(HttpHeaders.PRAGMA, "no-cache");
        // Http 1.1 header
        response.setHeader(HttpHeaders.CACHE_CONTROL, "no-cache, no-store, max-age=0");
    }

    /**
     * LastModified Header.
     */
    public static void setLastModifiedHeader(HttpServletResponse response, long lastModifiedDate) {
        response.setDateHeader(HttpHeaders.LAST_MODIFIED, lastModifiedDate);
    }

    /**
     * Etag Header.
     */
    public static void setEtag(HttpServletResponse response, String etag) {
        response.setHeader(HttpHeaders.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(HttpHeaders.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(HttpHeaders.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(HttpHeaders.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(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=\"" + encodedfileName + "\"");
        } catch (UnsupportedEncodingException e) {
        }
    }

    /**
     * ???Request Parameters, copy from spring WebUtils.
     * 
     * Parameter???.
     */
    @SuppressWarnings("rawtypes")
    public static Map<String, Object> getParametersStartingWith(ServletRequest request, String prefix) {
        Validate.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;
    }

    /**
     * ?Parameters?Query StringParameter, paramter nameprefix.
     * 
     * @see #getParametersStartingWith
     */
    public static String encodeParameterStringWithPrefix(Map<String, Object> params, String prefix) {
        if (params == null || params.size() == 0) {
            return "";
        }

        if (prefix == null) {
            prefix = "";
        }

        StringBuilder queryStringBuilder = new StringBuilder();
        Iterator<Entry<String, Object>> it = params.entrySet().iterator();
        while (it.hasNext()) {
            Entry<String, Object> entry = it.next();
            queryStringBuilder.append(prefix).append(entry.getKey()).append('=').append(entry.getValue());
            if (it.hasNext()) {
                queryStringBuilder.append('&');
            }
        }
        return queryStringBuilder.toString();
    }

    /**
     * Http Basic? Header?.
     */
    public static String encodeHttpBasic(String userName, String password) {
        String encode = userName + ":" + password;
        return "Basic " + Encodes.encodeBase64(encode.getBytes());
    }

    /**
     * ?URL
     * 
     * @param request
     * @return
     */
    public static String getRequestPath(HttpServletRequest request) {
        return StringUtils.substringAfter(request.getRequestURI(), request.getContextPath());
    }

    public static String getRequestPage(HttpServletRequest request) {
        return StringUtils.substringAfterLast(request.getRequestURI(), "/");
    }

    public static String getRequestFullPath(HttpServletRequest request) {
        return getRequestPath(request) + "?" + request.getQueryString();
    }

    public static String getHeaderValue(HttpServletRequest request, String name) {
        String value = request.getHeader(name);
        if (StringUtils.isBlank(value)) {
            value = request.getHeader(StringUtils.lowerCase(name));
        }
        return value;
    }

    @SuppressWarnings("unchecked")
    public static List<String> getHeaderValues(HttpServletRequest request, String name) {
        Enumeration<String> e = request.getHeaders(name);
        List<String> values = Lists.newArrayList();
        while (e.hasMoreElements()) {
            values.add(e.nextElement());
        }
        return values;
    }

    @SuppressWarnings("unchecked")
    public static Map<String, String> getHeaders(HttpServletRequest request, String prefixName) {
        Enumeration<String> names = request.getHeaderNames();
        String name = null;
        Map<String, String> map = Maps.newLinkedHashMap();
        while (names.hasMoreElements()) {
            name = names.nextElement();
            if (StringUtils.isNotBlank(prefixName)) {
                if (StringUtils.startsWithIgnoreCase(name, prefixName)) {
                    map.put(StringUtils.lowerCase(name), getHeaderValue(request, name));
                }
            } else {
                map.put(StringUtils.lowerCase(name), getHeaderValue(request, name));
            }
        }
        return map;
    }

    public static void setHeader(HttpServletResponse response, String name, String value) {
        response.setHeader(name, value);
    }

    public static void setHeaders(HttpServletResponse response, Map<String, String> map) {
        for (Map.Entry<String, String> entry : map.entrySet()) {
            setHeader(response, entry.getKey(), entry.getValue());
        }
    }

    public static String getQueryString(HttpServletRequest request) {
        return getRequestPath(request) + "?" + request.getQueryString();
    }

}