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