JSP根據IP統計訪問次數

本文簡要介紹如何實現一個IP訪問計數器。

為了簡單, 使用 JSP 來實現, 但讀者需要明白, Java程式碼可以在到處執行。

下面列出實現程式碼, 文件和說明就在程式碼中:

解析客戶端IP的工具類 IPUtils.java :

package com.cncounter.util.net;
import javax.servlet.http.HttpServletRequest;

/**
 * IP工具類
 */
public class IPUtils {

    public static final String SEMICOLON = ";"
 
;

    // Nginx代理傳遞的實際客戶端 IP-header
    public static final String[] HEADERS_TO_TRY = {
            "X-Forwarded-For",
            "X-REAL-IP",
            "Proxy-Client-IP",
            "WL-Proxy-Client-IP",
            "HTTP_X_FORWARDED_FOR",
            "HTTP_X_FORWARDED",
            "HTTP_X_CLUSTER_CLIENT_IP"
 
,
            "HTTP_CLIENT_IP",
            "HTTP_FORWARDED_FOR",
            "HTTP_FORWARDED",
            "HTTP_VIA",
            "REMOTE_ADDR",
            "REMOTE-HOST"
    };

    /**
     * 獲取客戶端的IP地址
     */
    public static String getClientIp(HttpServletRequest request) {
        String clientIp = _getClientIp(request);
        if
 
 (null != clientIp && !clientIp.trim().isEmpty()) {
            return clientIp;
        }
        return request.getRemoteAddr();
    }

    private static String _getClientIp(HttpServletRequest request) {
        for (String header : HEADERS_TO_TRY) {
            String ip = request.getHeader(header);
            if (ip != null && ip.length() != 0 && !"unknown".equalsIgnoreCase(ip)) {
                return ip;
            }
        }
        return request.getRemoteAddr();
    }
}

改為其他JSON庫也可以。但強烈推薦使用簡單強大靈活的FastJSON。

JSP檔案 counter.jsp 實現程式碼如下:

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8" isErrorPage="true" %>
<%@ page trimDirectiveWhitespaces="true" %>
<%@ page import="java.util.concurrent.ConcurrentHashMap" %>
<%@ page import="java.util.concurrent.atomic.AtomicInteger" %>
<%@ page import="com.cncounter.util.net.IPUtils" %>
<%@ page import="com.alibaba.fastjson.JSON" %>
<%-- trimDirectiveWhitespaces 的作用是去除多餘的空行 --%>
<%!
    // 訪問計數器Map<IP地址, 次數>
    private static ConcurrentHashMap<String, AtomicInteger> visitCounterMap
            = new ConcurrentHashMap<String, AtomicInteger>();

    // 增加並獲取最新的訪問次數
    private static int incrementCounter(String clientIp) {
        //
        AtomicInteger visitCounter = visitCounterMap.get(clientIp);
        if (null == visitCounter) {
            visitCounter = new AtomicInteger();
            AtomicInteger oldValue = visitCounterMap.putIfAbsent(clientIp, visitCounter);
            if (null != oldValue) {
                // 使用 putIfAbsent 時注意: 判斷是否有併發導致的原有值。
                visitCounter = oldValue;
            }
        }
        // 先增加, 再返回
        int count = visitCounter.incrementAndGet();
        return count;
    }

    // 清除某個IP的訪問次數
    private static int clearCounter(String clientIp) {
        visitCounterMap.remove(clientIp);
        return 0;
    }

    //
    private static final String CONST_PARAM_NAME_ACTION = "action";
    private static final String CONST_ACTION_VALUE_CLEAR = "clear";
    //
    private static final String CONST_PARAM_NAME_FORMAT = "format";
    private static final String CONST_FORMAT_VALUE_JSON = "json";
    //
    private static final String CONST_ATTR_NAME_CLIENTIP = "clientIp";
    private static final String CONST_ATTR_NAME_VISITCOUNT = "visitCount";
%>
<%
    // 獲取客戶端IP地址
    String clientIp = IPUtils.getClientIp(request);
    Integer visitCount = 0;
    if (null != clientIp) {
        // 獲取訪問次數
        visitCount = incrementCounter(clientIp);
    }
    // 如果需要清空資料
    String action = request.getParameter(CONST_PARAM_NAME_ACTION);
    if (CONST_ACTION_VALUE_CLEAR.equalsIgnoreCase(action)) {
        visitCount = clearCounter(clientIp);
    }
    // 如果需要返回JSON格式的資料
    String format = request.getParameter(CONST_PARAM_NAME_FORMAT);
    if (CONST_FORMAT_VALUE_JSON.equalsIgnoreCase(format)) {
        // 返回JSON
        Map<String, Object> result = new HashMap<String, Object>();
        result.put(CONST_ATTR_NAME_CLIENTIP, clientIp);
        result.put(CONST_ATTR_NAME_VISITCOUNT, visitCount);
%>
<%=JSON.toJSONString(result)%>
<%
        return; // 如果返回JSON資料, 則不往下執行
    }
%>
<HTML>
<HEAD>
    <TITLE>統計頁面訪問次數</TITLE>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
    <meta name="viewport"
          content="width=device-width, initial-scale=1, maximum-scale=1, minimum-scale=1, user-scalable=no">
    <meta charset="utf-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1">
    <style>
        body {
            word-wrap: break-word;
            word-break: break-all;
        }
    </style>
</HEAD>
<BODY>

<H1>統計頁面訪問次數</H1>
<table border="1" width="100%">

    <thead>
    <tr>
        <td align="center">
            <h3>IP地址</h3>
        </td>
        <td align="center">
            <h3>訪問次數</h3>
        </td>
    </tr>
    </thead>
    <tbody>
    <%
        Set<String> keySet = visitCounterMap.keySet();
        // 排序?
        // 根據值排序?
        for (String key : keySet) {
    %>
    <tr>
        <td>
            <%=key%>
        </td>
        <td>
            <%=visitCounterMap.getOrDefault(key, new AtomicInteger(0)).intValue()%>
        </td>
    </tr>
    <%
        }
    %>
    </tbody>
</table>

</BODY>
</HTML>

並未進行持久化, 如有需要, 可以定時儲存到資料庫。

只需要在儲存之後清空本地的值即可。

一般情況下, 統計訪問次數等功能, 不需要考慮極端情況, 只要不影響系統的效能即可。

然後訪問相應的地址:

返回的JSON 如下所示:

{"clientIp":"161.50.103.90","visitCount":4}

時間: 2018年2月9日