httpclient发送post请求获取token

好的，以下是一个使用Apache HttpClient发送POST请求获取Token的示例代码：

import java.io.IOException;
import java.net.URI;
import java.net.URISyntaxException;
import java.nio.charset.StandardCharsets;
import java.util.ArrayList;
import java.util.List;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.client.utils.URIBuilder;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.util.EntityUtils;

public class TokenUtils {
    private static final String TOKEN_URL = "http://example.com/token";
    private static final String CLIENT_ID = "your_client_id";
    private static final String CLIENT_SECRET = "your_client_secret";

    public static String getToken() throws IOException, URISyntaxException {
        HttpPost httpPost = new HttpPost(new URI(TOKEN_URL));
        List<NameValuePair> params = new ArrayList<>();
        params.add(new BasicNameValuePair("grant_type", "client_credentials"));
        params.add(new BasicNameValuePair("client_id", CLIENT_ID));
        params.add(new BasicNameValuePair("client_secret", CLIENT_SECRET));
        httpPost.setEntity(new UrlEncodedFormEntity(params, StandardCharsets.UTF_8));

        HttpResponse response = HttpClients.createDefault().execute(httpPost);
        HttpEntity entity = response.getEntity();
        if (entity != null) {
            String responseString = EntityUtils.toString(entity, StandardCharsets.UTF_8);
            // 解析JSON获取Token
            return parseToken(responseString);
        } else {
            throw new IOException("Response entity is null");
        }
    }

    private static String parseToken(String jsonString) {
        // 解析JSON字符串获取Token
        // ...
    }
}

在上面的代码中，我们首先定义了获取Token的URL地址、客户端ID和客户端密钥等参数。然后，我们创建了一个HttpPost对象，设置了请求参数，并使用HttpClients.createDefault()方法创建了一个HttpClient对象并执行POST请求。接着，我们获取响应实体，并使用EntityUtils.toString()方法将其转换为字符串类型。最后，我们调用parseToken()方法解析JSON字符串获取Token。

需要注意的是，这里的代码抛出了IOException和URISyntaxException异常，你需要在调用该方法时进行异常处理。