Filter中獲取傳遞參數的方式

這篇文章主要講解了“Filter中獲取傳遞參數的方式”，文中的講解內容簡單清晰，易于學習與理解，下面請大家跟著小編的思路慢慢深入，一起來研究和學習“Filter中獲取傳遞參數的方式”吧！

目錄

• Filter中獲取傳遞參數

• 1. GET 傳遞

• 2. Post 傳遞

• XyRequestWrapper 類

• XySecurityFilter

Filter中獲取傳遞參數

1. GET 傳遞

參數可以直接通過request.getParameter獲取。

2. Post 傳遞

產生不能過直接從request.getInputStream() 讀取，必須要進行重新寫。（request.getInputStream()只能夠讀取一次）

方式：

通過重寫 HttpServletRequestWrapper 類 獲取getInputStream中的流數據，然后在將body數據進行重新寫入傳遞下去。

XyRequestWrapper 類

package com.xy.boot.cmiap.filter; 
import com.alibaba.fastjson.JSONObject;
import com.xy.boot.common.util.StringUtils;
import org.apache.catalina.servlet4preview.http.HttpServletRequestWrapper;
import org.apache.commons.codec.Charsets;
 
import javax.servlet.ReadListener;
import javax.servlet.ServletInputStream;
import javax.servlet.http.HttpServletRequest;
import java.io.*;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.Map;
 
/**
 * Created by fuwenshen
 * Date:2018/10/26
 * Time:12:21
 */
public class XyRequestWrapper extends HttpServletRequestWrapper { 
    private String body; 
    public XyRequestWrapper(HttpServletRequest request) throws IOException {
        super(request);
        StringBuilder stringBuilder = new StringBuilder();
        BufferedReader bufferedReader = null;
        try {
            InputStream inputStream = request.getInputStream();
            if (inputStream != null) {
                bufferedReader = new BufferedReader(new InputStreamReader(inputStream,"UTF-8"));
                char[] charBuffer = new char[128];
                int bytesRead = -1;
                while ((bytesRead = bufferedReader.read(charBuffer)) > 0) {
                    stringBuilder.append(charBuffer, 0, bytesRead);
                }
            } else {
                stringBuilder.append("");
            }
        } catch (IOException ex) {
            throw ex;
        } finally {
            if (bufferedReader != null) {
                try {
                    bufferedReader.close();
                } catch (IOException ex) {
                    throw ex;
                }
            }
        }
        body = stringBuilder.toString();
    } 
 
    @Override
    public ServletInputStream getInputStream() throws IOException {
        final ByteArrayInputStream byteArrayInputStream = new ByteArrayInputStream(body.getBytes("UTF-8"));
        ServletInputStream servletInputStream = new ServletInputStream() {
            @Override
            public boolean isFinished() {
                return false;
            }
 
            @Override
            public boolean isReady() {
                return false;
            }
 
            @Override
            public void setReadListener(ReadListener readListener) {
 
            }
 
            @Override
            public int read() throws IOException {
                return byteArrayInputStream.read();
            }
        };
        return servletInputStream;
    } 
 
    @Override
    public BufferedReader getReader() throws IOException {
        return new BufferedReader(new InputStreamReader(this.getInputStream(), Charsets.UTF_8));
    }
 
    public String getBody() {
        return this.body;
    } 
 
    @Override
    public String getParameter(String name) {
        return super.getParameter(name);
    }
 
    @Override
    public Map<String, String[]> getParameterMap() {
        return super.getParameterMap();
    }
 
    @Override
    public Enumeration<String> getParameterNames() {
        return super.getParameterNames();
    }
 
    @Override
    public String[] getParameterValues(String name) {
        return super.getParameterValues(name);
    } 
 
    /**
     * 設置自定義post參數 //
     *
     * @param paramMaps
     * @return
     */
    public void setParamsMaps(Map paramMaps) {
        Map paramBodyMap = new HashMap();
        if (!StringUtils.isEmpty(body)) {
            paramBodyMap = JSONObject.parseObject(body, Map.class);
        }
        paramBodyMap.putAll(paramMaps);
        body = JSONObject.toJSONString(paramBodyMap);
    }
}

XySecurityFilter

package com.xy.boot.cmiap.filter; 
import com.alibaba.fastjson.JSONObject;
import com.xy.boot.cmiap.bo.VerifyTokenResultBO;
import com.xy.boot.cmiap.constant.HttpConstant;
import com.xy.boot.cmiap.entity.enums.XyHttpCodeEnum;
import com.xy.boot.cmiap.service.IXySecurityService;
import com.xy.boot.cmiap.service.helper.XyHttpSecurityHelper;
import com.xy.boot.common.util.StringUtils;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.http.MediaType;
import org.springframework.stereotype.Component;
 
import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.*;
 
/**
 * Created by fuwenshen
 * Date:2018/10/29
 * Time:15:36
 */
@Component
@Slf4j
@WebFilter(filterName = "xySecurityFilter", urlPatterns = {"/api/adv/*"})
public class XySecurityFilter implements Filter {
 
    @Value("${verify_token_switch}")
    private boolean tokenSwitch;
    @Value("${zy.app_secret}")
    private String zyAppSecret;
    @Value("${zy.token}")
    private String zyToken;
 
    //驗證 token bo
    private VerifyTokenResultBO tokenBO=null;
 
    @Autowired
    private IXySecurityService iXySecurityService;
 
    @Override
    public void init(FilterConfig filterConfig) throws ServletException { 
    }
 
    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
        log.debug("進入XySecurityFilter！");
        // 參數集合 初始化
        TreeMap paramsMaps = new TreeMap();
        String token = null, v = null, timestamp = null, sign = null;
 
        HttpServletRequest req = (HttpServletRequest) request;
        HttpServletResponse resp = (HttpServletResponse) response;
        resp.setCharacterEncoding("UTF-8");
        resp.setContentType(MediaType.APPLICATION_JSON_UTF8_VALUE);
        /**
         * 驗證通用請求頭是否完整
         */
        token = req.getHeader(HttpConstant.TOKEN);
        v = req.getHeader(HttpConstant.V);
        timestamp = req.getHeader(HttpConstant.TIMESTAMP);
        sign = req.getHeader(HttpConstant.SIGN);
        if (StringUtils.isEmpty(token) || StringUtils.isEmpty(v) || StringUtils.isEmpty(timestamp) || StringUtils.isEmpty(sign)) {
            resp.sendError(XyHttpCodeEnum.ILLEGAL_REQUEST.getCode(), XyHttpCodeEnum.ILLEGAL_REQUEST.getMessage());
            return;
        }
 
        // 防止流讀取一次后就沒有了, 所以需要將流繼續寫出去
        XyRequestWrapper requestWrapper = new XyRequestWrapper(req);
 
        /**
         * 校驗token
         */
        /*********************************************************/ 
 
        /**
         * 獲取請求參數
         */
        if ("POST".equals(req.getMethod().toUpperCase())) {
            String body = requestWrapper.getBody();
            paramsMaps = JSONObject.parseObject(body, TreeMap.class);
            log.debug("parameterMap:" + paramsMaps.toString());
 
        } else {
 
            Map<String, String[]> parameterMap = requestWrapper.getParameterMap();
            Set<Map.Entry<String, String[]>> entries = parameterMap.entrySet();
            Iterator<Map.Entry<String, String[]>> iterator = entries.iterator();
            while (iterator.hasNext()) {
                Map.Entry<String, String[]> next = iterator.next();
                paramsMaps.put(next.getKey(), next.getValue()[0]);
            }
            log.debug("parameterMap:" + paramsMaps.toString());
        } 
 
        /**
         * 驗證簽名是否合法
         */
        /***************************************/
 
        //設置企業信息（自定義參數）
        if(tokenBO!=null){
            Map paramsPlus = new HashMap();
            paramsPlus.put(HttpConstant.TOKEN, tokenBO.getTokenCode());
            paramsPlus.put(HttpConstant.APPID, tokenBO.getAppid());
            requestWrapper.setParamsMaps(paramsPlus);
        }
 
        chain.doFilter(requestWrapper, response); 
    } 
 
    @Override
    public void destroy() { 
    }
}

感謝各位的閱讀，以上就是“Filter中獲取傳遞參數的方式”的內容了，經過本文的學習后，相信大家對Filter中獲取傳遞參數的方式這一問題有了更深刻的體會，具體使用情況還需要大家實踐驗證。這里是億速云，小編將為大家推送更多相關知識點的文章，歡迎關注！