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 ： \n" + 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();
}
}
……
详解Java中的Future、FutureTask的原理以及与线程池的搭配使用
.
来源：https://www.cnblogs.com/foolash/p/12168251.html