java发送form-data请求

好的，让我来回答你的问题。Java发送form-data请求可以采用Apache HttpComponents库的MultipartEntityBuilder类。以下是一个示例代码：

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

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.mime.MultipartEntityBuilder;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;

public class FormDataRequestDemo {

    public static void main(String[] args) throws ClientProtocolException, IOException {
        CloseableHttpClient httpClient = HttpClients.createDefault();
        HttpPost httpPost = new HttpPost("http://example.com/upload");
        
        MultipartEntityBuilder builder = MultipartEntityBuilder.create();
        builder.addTextBody("username", "john");
        builder.addTextBody("password", "password123");
        builder.addBinaryBody("file", new File("/path/to/myfile"), ContentType.DEFAULT_BINARY, "myfile.txt");
        HttpEntity entity = builder.build();
        
        httpPost.setEntity(entity);
        
        HttpResponse response = httpClient.execute(httpPost);
        HttpEntity responseEntity = response.getEntity();
        
        if (responseEntity != null) {
            System.out.println("Response content: " + EntityUtils.toString(responseEntity));
        }
    }
}

在这个示例代码中，我们使用了MultipartEntityBuilder类来构建一个multipart/form-data请求实体，并将其设置为HttpPost对象的请求实体。我们添加了一个普通文本部分（"username"和"password"），以及一个二进制部分（"file"）。最后我们执行HttpPost请求，并从响应实体中读取并打印出响应内容。