Web层辅助工具类

Java web开发中经常用到的一些方法：

import java.io.BufferedReader;
import java.net.InetAddress;
import java.net.UnknownHostException;
import java.util.List;
import java.util.Map;
import java.util.ResourceBundle;

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

import org.apache.commons.lang3.StringUtils;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import org.apache.shiro.SecurityUtils;
import org.apache.shiro.session.InvalidSessionException;
import org.apache.shiro.session.Session;
import org.apache.shiro.subject.Subject;import org.springframework.web.util.WebUtils;

import com.alibaba.fastjson.JSON;

/**
 * Web层辅助类*/
public final class WebUtil {
 
    private WebUtil() {
    }

    private static Logger logger = LogManager.getLogger();
    public static final String CURRENT_USER = "CURRENT_USER";

    /**
     * 获取指定Cookie的值
     *
     * @param cookies
     *            cookie集合
     * @param cookieName
     *            cookie名字
     * @param defaultValue
     *            缺省值
     * @return
     */
    public static final String getCookieValue(HttpServletRequest request, String cookieName, String defaultValue) {
        Cookie cookie = WebUtils.getCookie(request, cookieName);
        if (cookie == null) {
            return defaultValue;
        }
        return cookie.getValue();
    }

    /** 保存当前用户 */
    public static final void saveCurrentUser(Object user) {
        setSession(CURRENT_USER, user);
    }

    /** 保存当前用户 */
    public static final void saveCurrentUser(HttpServletRequest request, Object user) {
        setSession(request, CURRENT_USER, user);
    }

    /** 获取当前用户 */
    public static final Long getCurrentUser() {
        Subject currentUser = SecurityUtils.getSubject();
        if (null != currentUser) {
            try {
                Session session = currentUser.getSession();
                if (null != session) {
                    return (Long) session.getAttribute(CURRENT_USER);
                }
            } catch (InvalidSessionException e) {
                logger.error(e);
            }
        }
        return null;
    }

    /** 获取当前用户 */
    public static final Object getCurrentUser(HttpServletRequest request) {
        try {
            HttpSession session = request.getSession();
            if (null != session) {
                return session.getAttribute(CURRENT_USER);
            }
        } catch (InvalidSessionException e) {
            logger.error(e);
        }
        return null;
    }

    /**
     * 将一些数据放到ShiroSession中,以便于其它地方使用
     *
     * @see 比如Controller,使用时直接用HttpSession.getAttribute(key)就可以取到
     */
    public static final void setSession(Object key, Object value) {
        Subject currentUser = SecurityUtils.getSubject();
        if (null != currentUser) {
            Session session = currentUser.getSession();
            if (null != session) {
                session.setAttribute(key, value);
            }
        }
    }

    /**
     * 将一些数据放到ShiroSession中,以便于其它地方使用
     *
     * @see 比如Controller,使用时直接用HttpSession.getAttribute(key)就可以取到
     */
    public static final void setSession(HttpServletRequest request, String key, Object value) {
        HttpSession session = request.getSession();
        if (null != session) {
            session.setAttribute(key, value);
        }
    }

    /** 移除当前用户 */
    public static final void removeCurrentUser(HttpServletRequest request) {
        request.getSession().removeAttribute(CURRENT_USER);
    }

    /**
     * 获得国际化信息
     *
     * @param key
     *            键
     * @param request
     * @return
     */
    public static final String getApplicationResource(String key, HttpServletRequest request) {
        ResourceBundle resourceBundle = ResourceBundle.getBundle("ApplicationResources", request.getLocale());
        return resourceBundle.getString(key);
    }

    /**
     * 获得参数Map
     *
     * @param request
     * @return
     */
    public static final Map<String, Object> getParameterMap(HttpServletRequest request) {
        return WebUtils.getParametersStartingWith(request, null);
    }

    @SuppressWarnings("unchecked")
    public static Map<String, Object> getParameter(HttpServletRequest request) {
        String str, wholeStr = "";
        try {
            BufferedReader br = request.getReader();
            while ((str = br.readLine()) != null) {
                wholeStr += str;
            }
            if (StringUtils.isNotBlank(wholeStr)) {
                return JSON.parseObject(wholeStr, Map.class);
            }
        } catch (Exception e) {
            logger.error("", e);
        }
        return getParameterMap(request);
    }

    public static <T> T getParameter(HttpServletRequest request, Class<T> cls) {
        String str, wholeStr = "";
        try {
            BufferedReader br = request.getReader();
            while ((str = br.readLine()) != null) {
                wholeStr += str;
            }
            if (StringUtils.isNotBlank(wholeStr)) {
                return JSON.parseObject(wholeStr, cls);
            }
        } catch (Exception e) {
            logger.error("", e);
        }
        return Request2ModelUtil.covert(cls, request);
    }

    @SuppressWarnings("unchecked")
    public static <T> List<T> getParameters(HttpServletRequest request, Class<T> cls) {
        String str, wholeStr = "";
        try {
            BufferedReader br = request.getReader();
            while ((str = br.readLine()) != null) {
                wholeStr += str;
            }
            if (StringUtils.isNotBlank(wholeStr)) {
                return JSON.parseObject(wholeStr, List.class);
            }
        } catch (Exception e) {
            logger.error("", e);
        }
        return Request2ListUtil.covert(cls, request);
    }

    /** 获取客户端IP */
    public static final String getHost(HttpServletRequest request) {
        String ip = request.getHeader("X-Forwarded-For");
        if (ip != null && ip.indexOf(",") > 0) {
            // 对于通过多个代理的情况，第一个IP为客户端真实IP,多个IP按照','分割
            ip = ip.substring(0, ip.indexOf(","));
        }
        if (StringUtils.isBlank(ip) || "unknown".equalsIgnoreCase(ip)) {
            ip = request.getHeader("Proxy-Client-IP");
        }
        if (StringUtils.isBlank(ip) || "unknown".equalsIgnoreCase(ip)) {
            ip = request.getHeader("WL-Proxy-Client-IP");
        }
        if (StringUtils.isBlank(ip) || "unknown".equalsIgnoreCase(ip)) {
            ip = request.getHeader("HTTP_CLIENT_IP");
        }
        if (StringUtils.isBlank(ip) || "unknown".equalsIgnoreCase(ip)) {
            ip = request.getHeader("HTTP_X_FORWARDED_FOR");
        }
        if (StringUtils.isBlank(ip) || "unknown".equalsIgnoreCase(ip)) {
            ip = request.getHeader("X-Real-IP");
        }
        if (StringUtils.isBlank(ip) || "unknown".equalsIgnoreCase(ip)) {
            ip = request.getRemoteAddr();
        }
        if ("127.0.0.1".equals(ip) || "0:0:0:0:0:0:0:1".equals(ip)) {
            InetAddress inet = null;
            try {
                inet = InetAddress.getLocalHost();
                ip = inet.getHostAddress();
            } catch (UnknownHostException e) {
                logger.error(e);
            }
        }
        return ip;
    }
}