各位小伙伴百度的的短链接API访问地址已经更改，请使用下面的链接https://dwz.cn/admin/v2/create，其中需要的参数token请访问https://dwz.cn/console/apidoc自行获取，另附上我整理的代码，仅供参考：

public class ShortNetAddressUtil {
final static String CREATE_API = “https://dwz.cn/admin/v2/create”;
final static String TOKEN = “你的token”;

class UrlResponse {
    @SerializedName("Code")
    private int code;

    @SerializedName("ErrMsg")
    private String errMsg;

    @SerializedName("LongUrl")
    private String longUrl;

    @SerializedName("ShortUrl")
    private String shortUrl;

    public int getCode() {
        return code;
    }

    public void setCode(int code) {
        this.code = code;
    }

    public String getErrMsg() {
        return errMsg;
    }

    public void setErrMsg(String errMsg) {
        this.errMsg = errMsg;
    }

    public String getLongUrl() {
        return longUrl;
    }

    public void setLongUrl(String longUrl) {
        this.longUrl = longUrl;
    }

    public String getShortUrl() {
        return shortUrl;
    }

    public void setShortUrl(String shortUrl) {
        this.shortUrl = shortUrl;
    }
}

/**
 * 创建短网址
 *
 * @param longUrl
 *            长网址：即原网址
 * @return 成功：短网址 失败：返回空字符串
 */
public static String getShortURL(String longUrl) {
    String params = "{"url":"" + longUrl + ""}";

    BufferedReader reader = null;
    try {
        // 创建连接
        URL url = new URL(CREATE_API);
        HttpURLConnection connection = (HttpURLConnection) url.openConnection();
        connection.setDoOutput(true);
        connection.setDoInput(true);
        connection.setUseCaches(false);
        connection.setInstanceFollowRedirects(true);
        connection.setRequestMethod("POST"); // 设置请求方式
        connection.setRequestProperty("Content-Type", "application/json"); // 设置发送数据的格式
        connection.setRequestProperty("Token", TOKEN); // 设置发送数据的格式");

        // 发起请求
        connection.connect();
        OutputStreamWriter out = new OutputStreamWriter(connection.getOutputStream(), "UTF-8"); // utf-8编码
        out.append(params);
        out.flush();
        out.close();

        // 读取响应
        reader = new BufferedReader(new InputStreamReader(connection.getInputStream(), "UTF-8"));
        String line;
        String res = "";
        while ((line = reader.readLine()) != null) {
            res += line;
        }
        reader.close();

        // 抽取生成短网址
        UrlResponse urlResponse = new Gson().fromJson(res, UrlResponse.class);
        if (urlResponse.getCode() == 0) {
            return urlResponse.getShortUrl();
        } else {
            System.out.println(urlResponse.getErrMsg());
        }
        return "";
    } catch (IOException e) {
        e.printStackTrace();
    }
    return ""; 
}

public static void main(String[] args) {
    String res = getShortURL("https://mp.weixin.qq.com/debug/cgi-bin/sandbox?t=sandbox/login");
    System.out.println(res);

}

}

另外还需要引入额外的jar包：
groupId：com.google.code.gson
artifactId：gson
亲测运行正常，可以生成对应的短链接，如果有问题，欢迎讨论