封装Volley使Volley的每个请求都自动保存和发送Cookie

思路很简单，每次请求获取到服务器返回的response就解析头部获取cookie并保存，发送请求的时候就从本地读取cookie添加到头部发送给服务器

第一步，解析http response头部的cookie并保存，自定义一个Request并重写其parseNetworkResponse方法

/**
 * 解析数据，保存Cookie
 * @param response
 * @return
 */
@Override
protected Response<JSONObject> parseNetworkResponse(NetworkResponse response) {
try {
JSONObject jsonObject;
/*将response构造成JSONObject返回给调用者*/
 if (response.data.length != 0) {
String jsonString = new String(response.data, HttpHeaderParser.parseCharset(response.headers));
jsonObject = new JSONObject(jsonString);
        } else {
jsonObject = new JSONObject();
        }
/*获取数据头*/
 mHeader = response.headers.toString();
/*通过正则表达式提取Cookie(JSESSIONID)*/
 Pattern pattern = Pattern.compile("Set-Cookie=.*?;");
Matcher matcher = pattern.matcher(mHeader);
if (matcher.find()) {
cookieFromResp = matcher.group();
/*获取数据头中键为Set-Cookie的值即获取Cookie*/
 cookieFromResp = cookieFromResp.substring(11, cookieFromResp.length() - 1);
DLog.v("Cookie: " + cookieFromResp);
        }
/*将Cookie保存到本地，下次请求数据的时候再把本地保存的Cookie发送给服务器*/
 if(!TextUtils.isEmpty(cookieFromResp)){
CookieUtils.saveSessionID(App.getContext(),cookieFromResp);
        }
return Response.success(jsonObject,
HttpHeaderParser.parseCacheHeaders(response));
    } catch (UnsupportedEncodingException e) {
return Response.error(new ParseError(e));
    } catch (JSONException je) {
return Response.error(new ParseError(je));
    }
}

第二步，发送请求的时候，从本地读取Cookie，添加到http request的头部，发送给服务器，重写getHeaders()即可

/**
 * 设置header，自动发送本地保存的Cookie
 * @return
 * @throws AuthFailureError
 */
@Override
public Map<String, String> getHeaders() throws AuthFailureError {
headerMap.put("Accept", "application/json");
headerMap.put("Content-Type", "application/json; charset=UTF-8");
String cookie=CookieUtils.loadSessionID(App.getContext());
DLog.d(cookie);
/*将本地保存的Cookie发送给服务器*/
 if(!TextUtils.isEmpty(cookie)){
headerMap.put("Cookie", CookieUtils.loadSessionID(App.getContext()));
    }
return headerMap;
}

经过上边两个方法的重写就已经实现了Cookie的自动保存和自动发送

经过封装的完整的Request代码如下:

public class JsonObjectRequest extends JsonRequest<JSONObject > {
    private String mHeader;
    private String cookieFromResp = "";
    Map<String, String> headerMap = new HashMap<>();

    public JsonObjectRequest(int method, String url,
                             JSONObject jsonRequest,
                             Response.Listener<JSONObject> listener,
                             Response.ErrorListener errorListener) {
        super(  method,
                url,
                (jsonRequest == null) ? null : jsonRequest.toString(),
                listener,
                errorListener);
    }

    public JsonObjectRequest(String url,
                             JSONObject jsonRequest,
                             Response.Listener<JSONObject> listener,
                             Response.ErrorListener errorListener) {
        this(  jsonRequest == null ? Request.Method.GET : Request.Method.POST,
                url,
                jsonRequest,
                listener,
                errorListener);
    }

    /**
     * 解析数据，保存Cookie
     * @param response
     * @return
     */
    @Override
    protected Response<JSONObject> parseNetworkResponse(NetworkResponse response) {
        try {
            JSONObject jsonObject;
            /*将response构造成JSONObject返回给调用者*/
            if (response.data.length != 0) {
                String jsonString = new String(response.data, HttpHeaderParser.parseCharset(response.headers));
                jsonObject = new JSONObject(jsonString);
            } else {
                jsonObject = new JSONObject();
            }
            /*获取数据头*/
            mHeader = response.headers.toString();
            /*通过正则表达式提取Cookie(JSESSIONID)*/
            Pattern pattern = Pattern.compile("Set-Cookie=.*?;");
            Matcher matcher = pattern.matcher(mHeader);
            if (matcher.find()) {
                cookieFromResp = matcher.group();
                /*获取数据头中键为Set-Cookie的值即获取Cookie*/
                cookieFromResp = cookieFromResp.substring(11, cookieFromResp.length() - 1);
                DLog.v("Cookie: " + cookieFromResp);
            }
            /*将Cookie保存到本地，下次请求数据的时候再把本地保存的Cookie发送给服务器*/
            if(!TextUtils.isEmpty(cookieFromResp)){
                CookieUtils.saveSessionID(App.getContext(),cookieFromResp);
            }
            return Response.success(jsonObject,
                    HttpHeaderParser.parseCacheHeaders(response));
        } catch (UnsupportedEncodingException e) {
            return Response.error(new ParseError(e));
        } catch (JSONException je) {
            return Response.error(new ParseError(je));
        }
    }

    /**
     * 设置超时
     * @return
     */
    @Override
    public RetryPolicy getRetryPolicy() {
        RetryPolicy retryPolicy= new DefaultRetryPolicy(5000, DefaultRetryPolicy.DEFAULT_MAX_RETRIES,
                DefaultRetryPolicy.DEFAULT_BACKOFF_MULT);
        return retryPolicy;
    }

    /**
     * 设置header，自动发送本地保存的Cookie
     * @return
     * @throws AuthFailureError
     */
    @Override
    public Map<String, String> getHeaders() throws AuthFailureError {
        headerMap.put("Accept", "application/json");
        headerMap.put("Content-Type", "application/json; charset=UTF-8");
        String cookie=CookieUtils.loadSessionID(App.getContext());
        DLog.d(cookie);
        /*将本地保存的Cookie发送给服务器*/
        if(!TextUtils.isEmpty(cookie)){
            headerMap.put("Cookie", CookieUtils.loadSessionID(App.getContext()));
        }
        return headerMap;
    }
    //将Cookie加入数据头
    public void setCookie(String cookie) {
        headerMap.put("Cookie", cookie);
    }
}