一、注册

api.fanyi.baidu.com/ 登录进行一个注册，自己的

#二、准备MD5、``` TransApi

import java.io.*; import java.nio.charset.StandardCharsets; import java.security.MessageDigest; import java.security.NoSuchAlgorithmException;

public class MD5 { // 首先初始化一个字符数组，用来存放每个16进制字符 private static final char[] hexDigits = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };

/**
 * 获得一个字符串的MD5值
 *
 * @param input 输入的字符串
 * @return 输入字符串的MD5值
 *
 */
public static String md5(String input) throws UnsupportedEncodingException {
    if (input == null)
        return null;

    try {
        // 拿到一个MD5转换器（如果想要SHA1参数换成”SHA1”）
        MessageDigest messageDigest = MessageDigest.getInstance("MD5");
        // 输入的字符串转换成字节数组
        byte[] inputByteArray = input.getBytes("utf-8");
        // inputByteArray是输入字符串转换得到的字节数组
        messageDigest.update(inputByteArray);
        // 转换并返回结果，也是字节数组，包含16个元素
        byte[] resultByteArray = messageDigest.digest();
        // 字符数组转换成字符串返回
        return byteArrayToHex(resultByteArray);
    } catch (NoSuchAlgorithmException e) {
        return null;
    }
}

/**
 * 获取文件的MD5值
 *
 * @param file
 * @return
 */
public static String md5(File file) {
    try {
        if (!file.isFile()) {
            System.err.println("文件" + file.getAbsolutePath() + "不存在或者不是文件");
            return null;
        }

        FileInputStream in = new FileInputStream(file);

        String result = md5(in);

        in.close();

        return result;

    } catch (FileNotFoundException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    }

    return null;
}

public static String md5(InputStream in) {

    try {
        MessageDigest messagedigest = MessageDigest.getInstance("MD5");

        byte[] buffer = new byte[1024];
        int read = 0;
        while ((read = in.read(buffer)) != -1) {
            messagedigest.update(buffer, 0, read);
        }

        in.close();

        String result = byteArrayToHex(messagedigest.digest());

        return result;
    } catch (NoSuchAlgorithmException e) {
        e.printStackTrace();
    } catch (FileNotFoundException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    }

    return null;
}

private static String byteArrayToHex(byte[] byteArray) {
    // new一个字符数组，这个就是用来组成结果字符串的（解释一下：一个byte是八位二进制，也就是2位十六进制字符（2的8次方等于16的2次方））
    char[] resultCharArray = new char[byteArray.length * 2];
    // 遍历字节数组，通过位运算（位运算效率高），转换成字符放到字符数组中去
    int index = 0;
    for (byte b : byteArray) {
        resultCharArray[index++] = hexDigits[b >>> 4 & 0xf];
        resultCharArray[index++] = hexDigits[b & 0xf];
    }

    // 字符数组组合成字符串返回
    return new String(resultCharArray);

}

}

import org.springframework.beans.factory.annotation.Autowired; import org.springframework.beans.factory.annotation.Value; import org.springframework.stereotype.Service; import org.springframework.util.LinkedMultiValueMap; import org.springframework.util.MultiValueMap; import org.springframework.web.client.RestTemplate; import org.springframework.web.util.UriComponentsBuilder;

import java.io.UnsupportedEncodingException; import java.net.URI; import java.util.HashMap; import java.util.Map;

@Service public class TransApi { private static final String TRANS_API_HOST = "api.fanyi.baidu.com/api/trans/v…";

@Value("${baidu_translate.appid}")
private String appid;
@Value("${baidu_translate.securityKey}")
private String securityKey;

// 添加了一个无参构造器，不然无法注入这个bean，否则需要额外的配置。
public TransApi() {}

@Autowired
private RestTemplate restTemplate;

public TransApi(String appid, String securityKey) {
    this.appid = appid;
    this.securityKey = securityKey;
}

public String getTransResult(String query, String from, String to) throws UnsupportedEncodingException {
    Map<String, String> params = buildParams(query, from, to);
    MultiValueMap<String, String> requestParams = new LinkedMultiValueMap<>();
    requestParams.setAll(params);
    UriComponentsBuilder builder = UriComponentsBuilder.fromHttpUrl(TRANS_API_HOST);
    URI uri = builder.queryParams(requestParams).build().encode().toUri();  //  这里不能进行 encode 了，编码就错误了
    System.out.println("uri: " + uri);
    return restTemplate.getForObject(uri, String.class);
}

private Map<String, String> buildParams(String query, String from, String to) throws UnsupportedEncodingException {
    Map<String, String> params = new HashMap<String, String>();
    params.put("q", query);
    params.put("from", from);
    params.put("to", to);

    params.put("appid", appid);

    // 随机数
    String salt = String.valueOf(System.currentTimeMillis());
    params.put("salt", salt);

    // 签名
    String src = appid + query + salt + securityKey; // 加密前的原文
    params.put("sign", MD5.md5(src));

    return params;
}

}

# 测试

import com.hmy.testhh.service.TransApi; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.http.MediaType; import org.springframework.web.bind.annotation.GetMapping; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RequestParam; import org.springframework.web.bind.annotation.RestController;

import java.io.UnsupportedEncodingException;

@RestController @RequestMapping("/translate") public class TranslateController {

@Autowired
private TransApi transApi;

@GetMapping(value = "/query", produces = MediaType.APPLICATION_JSON_VALUE)
public String query(@RequestParam("query") String query,
                    @RequestParam("from") String from, @RequestParam("to") String to) throws UnsupportedEncodingException {
    return transApi.getTransResult(query, from, to);
}

}





![image.png](https://p1-juejin.byteimg.com/tos-cn-i-k3u1fbpfcp/e70f3ae97d9d413199ccb69ab9109a49~tplv-k3u1fbpfcp-watermark.image?)

调用百度翻译接口进行翻译

一、注册