Java HttpPost 数据流方式上传图片

Java中使用HttpPost实现数据流方式上传图片的步骤如下：

1. 创建HttpClient对象

CloseableHttpClient httpClient = HttpClients.createDefault();

2. 创建HttpPost对象，并设置请求URL

HttpPost httpPost = new HttpPost("http://example.com/upload");

3. 创建HttpEntity对象，并设置上传的文件和参数

MultipartEntityBuilder entityBuilder = MultipartEntityBuilder.create();
entityBuilder.setMode(HttpMultipartMode.BROWSER_COMPATIBLE);

// 设置文件参数
File file = new File("image.jpg");
entityBuilder.addBinaryBody("file", file, ContentType.DEFAULT_BINARY, file.getName());

// 设置其他参数
entityBuilder.addTextBody("name", "example");

HttpEntity httpEntity = entityBuilder.build();
httpPost.setEntity(httpEntity);

4. 执行HttpPost请求，并获取响应结果

CloseableHttpResponse httpResponse = httpClient.execute(httpPost);
HttpEntity responseEntity = httpResponse.getEntity();
String response = EntityUtils.toString(responseEntity);

完整的代码示例：

import java.io.File;
import java.io.IOException;

import org.apache.http.HttpEntity;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.ContentType;
import org.apache.http.entity.mime.HttpMultipartMode;
import org.apache.http.entity.mime.MultipartEntityBuilder;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.EntityUtils;

public class ImageUploader {
    public static void main(String[] args) throws IOException {
        CloseableHttpClient httpClient = HttpClients.createDefault();

        HttpPost httpPost = new HttpPost("http://example.com/upload");

        MultipartEntityBuilder entityBuilder = MultipartEntityBuilder.create();
        entityBuilder.setMode(HttpMultipartMode.BROWSER_COMPATIBLE);

        // 设置文件参数
        File file = new File("image.jpg");
        entityBuilder.addBinaryBody("file", file, ContentType.DEFAULT_BINARY, file.getName());

        // 设置其他参数
        entityBuilder.addTextBody("name", "example");

        HttpEntity httpEntity = entityBuilder.build();
        httpPost.setEntity(httpEntity);

        CloseableHttpResponse httpResponse = httpClient.execute(httpPost);
        HttpEntity responseEntity = httpResponse.getEntity();
        String response = EntityUtils.toString(responseEntity);

        System.out.println(response);
    }
}