百度ocr接口，Future限制调用的响应时间

一、百度提供的工具类

1.HttpUtil

package com.baidu.ai.aip.utils;

import java.io.BufferedReader;
import java.io.DataOutputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.List;
import java.util.Map;

/**
 * http 工具类
 */
public class HttpUtil {

    public static String post(String requestUrl, String accessToken, String params)
            throws Exception {
        String contentType = "application/x-www-form-urlencoded";
        return HttpUtil.post(requestUrl, accessToken, contentType, params);
    }

    public static String post(String requestUrl, String accessToken, String contentType, String params)
            throws Exception {
        String encoding = "UTF-8";
        if (requestUrl.contains("nlp")) {
            encoding = "GBK";
        }
        return HttpUtil.post(requestUrl, accessToken, contentType, params, encoding);
    }

    public static String post(String requestUrl, String accessToken, String contentType, String params, String encoding)
            throws Exception {
        String url = requestUrl + "?access_token=" + accessToken;
        return HttpUtil.postGeneralUrl(url, contentType, params, encoding);
    }

    public static String postGeneralUrl(String generalUrl, String contentType, String params, String encoding)
            throws Exception {
        URL url = new URL(generalUrl);
        // 打开和URL之间的连接
        HttpURLConnection connection = (HttpURLConnection) url.openConnection();
        connection.setRequestMethod("POST");
        // 设置通用的请求属性
        connection.setRequestProperty("Content-Type", contentType);
        connection.setRequestProperty("Connection", "Keep-Alive");
        connection.setUseCaches(false);
        connection.setDoOutput(true);
        connection.setDoInput(true);

        // 得到请求的输出流对象
        DataOutputStream out = new DataOutputStream(connection.getOutputStream());
        out.write(params.getBytes(encoding));
        out.flush();
        out.close();

        // 建立实际的连接
        connection.connect();
        // 获取所有响应头字段
        Map<String, List<String>> headers = connection.getHeaderFields();
        // 遍历所有的响应头字段
        for (String key : headers.keySet()) {
            System.err.println(key + "--->" + headers.get(key));
        }
        // 定义 BufferedReader输入流来读取URL的响应
        BufferedReader in = null;
        in = new BufferedReader(
                new InputStreamReader(connection.getInputStream(), encoding));
        String result = "";
        String getLine;
        while ((getLine = in.readLine()) != null) {
            result += getLine;
        }
        in.close();
        System.err.println("result:" + result);
        return result;
    }
}

2.FileUtil

package com.baidu.ai.aip.utils;

import java.io.*;

/**
 * 文件读取工具类
 */
public class FileUtil {

    /**
     * 读取文件内容，作为字符串返回
     */
    public static String readFileAsString(String filePath) throws IOException {
        File file = new File(filePath);
        if (!file.exists()) {
            throw new FileNotFoundException(filePath);
        } 

        if (file.length() > 1024 * 1024 * 1024) {
            throw new IOException("File is too large");
        } 

        StringBuilder sb = new StringBuilder((int) (file.length()));
        // 创建字节输入流  
        FileInputStream fis = new FileInputStream(filePath);  
        // 创建一个长度为10240的Buffer
        byte[] bbuf = new byte[10240];  
        // 用于保存实际读取的字节数  
        int hasRead = 0;  
        while ( (hasRead = fis.read(bbuf)) > 0 ) {  
            sb.append(new String(bbuf, 0, hasRead));  
        }  
        fis.close();  
        return sb.toString();
    }

    /**
     * 根据文件路径读取byte[] 数组
     */
    public static byte[] readFileByBytes(String filePath) throws IOException {
        File file = new File(filePath);
        if (!file.exists()) {
            throw new FileNotFoundException(filePath);
        } else {
            ByteArrayOutputStream bos = new ByteArrayOutputStream((int) file.length());
            BufferedInputStream in = null;

            try {
                in = new BufferedInputStream(new FileInputStream(file));
                short bufSize = 1024;
                byte[] buffer = new byte[bufSize];
                int len1;
                while (-1 != (len1 = in.read(buffer, 0, bufSize))) {
                    bos.write(buffer, 0, len1);
                }

                byte[] var7 = bos.toByteArray();
                return var7;
            } finally {
                try {
                    if (in != null) {
                        in.close();
                    }
                } catch (IOException var14) {
                    var14.printStackTrace();
                }

                bos.close();
            }
        }
    }
}

3.Base64Util

package com.baidu.ai.aip.utils;

/**
 * Base64 工具类
 */
public class Base64Util {
    private static final char last2byte = (char) Integer.parseInt("00000011", 2);
    private static final char last4byte = (char) Integer.parseInt("00001111", 2);
    private static final char last6byte = (char) Integer.parseInt("00111111", 2);
    private static final char lead6byte = (char) Integer.parseInt("11111100", 2);
    private static final char lead4byte = (char) Integer.parseInt("11110000", 2);
    private static final char lead2byte = (char) Integer.parseInt("11000000", 2);
    private static final char[] encodeTable = new char[]{'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '+', '/'};

    public Base64Util() {
    }

    public static String encode(byte[] from) {
        StringBuilder to = new StringBuilder((int) ((double) from.length * 1.34D) + 3);
        int num = 0;
        char currentByte = 0;

        int i;
        for (i = 0; i < from.length; ++i) {
            for (num %= 8; num < 8; num += 6) {
                switch (num) {
                    case 0:
                        currentByte = (char) (from[i] & lead6byte);
                        currentByte = (char) (currentByte >>> 2);
                    case 1:
                    case 3:
                    case 5:
                    default:
                        break;
                    case 2:
                        currentByte = (char) (from[i] & last6byte);
                        break;
                    case 4:
                        currentByte = (char) (from[i] & last4byte);
                        currentByte = (char) (currentByte << 2);
                        if (i + 1 < from.length) {
                            currentByte = (char) (currentByte | (from[i + 1] & lead2byte) >>> 6);
                        }
                        break;
                    case 6:
                        currentByte = (char) (from[i] & last2byte);
                        currentByte = (char) (currentByte << 4);
                        if (i + 1 < from.length) {
                            currentByte = (char) (currentByte | (from[i + 1] & lead4byte) >>> 4);
                        }
                }

                to.append(encodeTable[currentByte]);
            }
        }

        if (to.length() % 4 != 0) {
            for (i = 4 - to.length() % 4; i > 0; --i) {
                to.append("=");
            }
        }

        return to.toString();
    }
}

4.GsonUtils

/*
 * Copyright (C) 2017 Baidu, Inc. All Rights Reserved.
 */
package com.baidu.ai.aip.utils;

import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import com.google.gson.JsonParseException;

import java.lang.reflect.Type;

/**
 * Json工具类.
 */
public class GsonUtils {
    private static Gson gson = new GsonBuilder().create();

    public static String toJson(Object value) {
        return gson.toJson(value);
    }

    public static <T> T fromJson(String json, Class<T> classOfT) throws JsonParseException {
        return gson.fromJson(json, classOfT);
    }

    public static <T> T fromJson(String json, Type typeOfT) throws JsonParseException {
        return (T) gson.fromJson(json, typeOfT);
    }
}

二、ocr接口调用

import com.alibaba.fastjson.JSON;import io.swagger.annotations.Api;
import io.swagger.annotations.ApiParam;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URLEncoder;
import java.util.Calendar;
import java.util.concurrent.*;

@Slf4j
@RestController
@RequestMapping(value = "api/ocr")
@Api(value = "百度ocr接口", description = "百度ocr接口")
public class BaiDuOcrController {


    @Autowired
    private BaiduOcrToken ocr;

    private JSONObject auth;
    private long expireDate;
    private int limitTime = 5700;


   /* @PostConstruct
    public void initOcrToken() {
        initOcrAuth();
    }*/

    /**
     * 初次调用或已经过期，初始化百度ocr调用权限
     */
    public void initOcrAuth() {
        log.info("初次调用或已经过期，初始化百度ocr调用权限Accesstoken开始");
        auth = getAuth(ocr.getClientId(), ocr.getClientSecret());
        log.info("初始化百度ocr调用权限Accesstoken成功 ： 
" + auth);

        String expiresIn = auth.getString("expires_in");
        Calendar calendar = Calendar.getInstance();
        calendar.add(Calendar.SECOND, Integer.valueOf(expiresIn));

        expireDate = calendar.getTimeInMillis();
        log.info("初始化百度ocr调用权限Accesstoken成功，过期时间 ======= " + expireDate);
    }


    /**
     * 获取API访问token
     * 该token有一定的有效期，需要自行管理，当失效时需重新获取.
     * @param ak - 百度云官网获取的 API Key
     * @param sk - 百度云官网获取的 Securet Key
     * @return assess_token 示例：
     * "24.460da4889caad24cccdb1fea17221975.2592000.1491995545.282335-1234567"
     */
    public JSONObject getAuth(String ak, String sk) {
        // 获取token地址
        String authHost = ocr.getOcrAuthApi();
        String getAccessTokenUrl = authHost
                // 1. grant_type为固定参数
                + "grant_type=client_credentials"
                // 2. 官网获取的 API Key
                + "&client_id=" + ak
                // 3. 官网获取的 Secret Key
                + "&client_secret=" + sk;
        try {
            // 打开和URL之间的连接
            HttpURLConnection connection = FileHelper.getHttpURLConnection(getAccessTokenUrl);
            connection.setRequestMethod("POST");
            connection.connect();

            // 定义 BufferedReader输入流来读取URL的响应
            BufferedReader in = new BufferedReader(new InputStreamReader(connection.getInputStream()));
            String result = "";
            String line;
            while ((line = in.readLine()) != null) {
                result += line;
            }
            /* 返回结果 */
            JSONObject jo = JSON.parseObject(result);
            return jo;
        } catch (Exception e) {
            log.error("获取百度ocr访问权限token失败！", e);
        }
        return null;
    }


    @RequestMapping(value = "auth", method = RequestMethod.GET)
    public Result<Boolean> ocrAccessToken() {

        if(expireDate == 0 || System.currentTimeMillis() >= expireDate) {
            initOcrAuth();
        }

        return Result.success().result(true);
    }


    @RequestMapping(value = "idcard", method = RequestMethod.POST)
    public Result<String> idcard(@ApiParam(value = "front：身份证含照片的一面；back：身份证带国徽的一面") String idCardSide,
                                 @ApiParam(value = "身份证url地址")String imgUrl) throws Exception {

        Future<String> future = null;
        try {

            future = ConcurrentUtil.getThreadPool().submit( () -> {
                byte[] imgData = FileHelper.readBytesByUrl(imgUrl);
                String imgStr = Base64Util.encode(imgData);
                String imgParam = URLEncoder.encode(imgStr, "UTF-8");

                String param = "id_card_side=" + idCardSide + "&image=" + imgParam + "&detect_direction=true";

                // 注意这里仅为了简化编码每一次请求都去获取access_token，线上环境access_token有过期时间， 客户端可自行缓存，过期后重新获取。
                String accessToken = auth.getString("access_token");

                String result = HttpUtil.post(ocr.getIdcardApi(), accessToken, param);

                return result;
            });

            String result = future.get(limitTime, TimeUnit.MILLISECONDS);

            return Result.success().result(result);

        } catch (Exception  e) {
            if(future != null)
                future.cancel(true);
            log.error("身份证识别失败, url为 : {}", imgUrl);
            throw e;
        }
    }


    @RequestMapping(value = "bankCard", method = RequestMethod.POST)
    public Result<String> bankCard(@ApiParam(value = "银行卡url地址") String imgUrl) throws Exception {

        Future<String> future = null;
        try {

            future = ConcurrentUtil.getThreadPool().submit( () -> {

                byte[] imgData = FileHelper.readBytesByUrl(imgUrl);
                String imgStr = Base64Util.encode(imgData);
                String imgParam = URLEncoder.encode(imgStr, "UTF-8");

                String param = "image=" + imgParam;

                // 注意这里仅为了简化编码每一次请求都去获取access_token，线上环境access_token有过期时间， 客户端可自行缓存，过期后重新获取。
                String accessToken = auth.getString("access_token");

                String result = HttpUtil.post(ocr.getBankcardApi(), accessToken, param);

                return result;
            });

            String result = future.get(limitTime, TimeUnit.MILLISECONDS);

            return Result.success().result(result);

        } catch (Exception  e) {
            if(future != null)
                future.cancel(true);
            log.error("银行卡识别失败, url为 : {}", imgUrl);
            throw e;
        }
    }


    @RequestMapping(value = "businessLicense", method = RequestMethod.POST)
    public Result businessLicense(@ApiParam(value = "营业执照url地址") String imgUrl) throws Exception {

        Future<String> future = null;
        try {


            /*Callable<String> callable = new Callable<String>() {
                @Override
                public String call() throws Exception {

                    return "";
                }
            };

            FutureTask<String> futureTask = new FutureTask<>(callable);*/


            future = ConcurrentUtil.getThreadPool().submit( () -> {

                byte[] imgData = FileHelper.readBytesByUrl(imgUrl);
                String imgStr = Base64Util.encode(imgData);
                String imgParam = URLEncoder.encode(imgStr, "UTF-8");

                String param = "image=" + imgParam + "&detect_direction=true";//&accuracy=high";

                // 注意这里仅为了简化编码每一次请求都去获取access_token，线上环境access_token有过期时间， 客户端可自行缓存，过期后重新获取。
                String accessToken = auth.getString("access_token");

                String result = HttpUtil.post(ocr.getLicenseApi(), accessToken, param);
                return result;
            });
            //加上前端请求时间限制在6s，超过强制返回结果，取消识别
            String result = future.get(limitTime, TimeUnit.MILLISECONDS);

            return Result.success().result(result);

        } catch (Exception  e) {
            if(future != null)
                future.cancel(true);
            log.error("营业执照识别失败, url为 : {}", imgUrl);
            throw e;
        }
    }

    @RequestMapping(value = "words", method = RequestMethod.POST)
    public Result words(String imgUrl) throws Exception {

        String url = "https://aip.baidubce.com/rest/2.0/ocr/v1/general";

        String param = "url=" + imgUrl + "&detect_direction=true";
        // 注意这里仅为了简化编码每一次请求都去获取access_token，线上环境access_token有过期时间， 客户端可自行缓存，过期后重新获取。
        String accessToken = auth.getString("access_token");

        String result = HttpUtil.post("https://aip.baidubce.com/rest/2.0/ocr/v1/general", accessToken, param);

        return Result.success().result(result);
    }

}

根据url读取图片内容:

HttpURLConnection -> conn.getContentLength();图片内容长度

/**
     * 根据ali oss url读取文件字节
     * @param imgUrl
     * @return
     * @throws IOException
     */
    public static byte[] readBytesByUrl(String imgUrl) throws IOException {

        String limitUrl = FileHelper.limit500KbImgUrl(imgUrl);
        HttpURLConnection conn = FileHelper.getHttpURLConnection(limitUrl);
        InputStream ins = FileHelper.getInputStreaFromConnection(conn);

        ByteArrayOutputStream bos = new ByteArrayOutputStream();
        BufferedInputStream bis;

        try {
            bis = new BufferedInputStream(ins);
            short bufSize = 1024;
            byte[] buffer = new byte[bufSize];
            int len1;
            while (-1 != (len1 = bis.read(buffer, 0, bufSize))) {
                bos.write(buffer, 0, len1);
            }

            byte[] bytes = bos.toByteArray();
            return bytes;
        } finally {
            try {
                if (ins != null) {
                    ins.close();
                }
            } catch (IOException var14) {
                ;
            }

            bos.close();
        }
    }

……

 百度api地址

JAVA Future类详解

详解Java中的Future、FutureTask的原理以及与线程池的搭配使用

.