写一个httpclient接口上传文件的java代码

好的，这是一个简单的Httpclient上传文件的Java代码：

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.ContentType;
import org.apache.http.entity.mime.MultipartEntityBuilder;
import org.apache.http.entity.mime.content.FileBody;
import org.apache.http.impl.client.DefaultHttpClient;

import java.io.File;

public class HttpclientUpload {

    public static void main(String[] args) {

        // 提交的文件路径
        String filePath = "C:\\Users\\User\\Desktop\\test.txt";
        // 上传的地址
        String uploadUrl = "http://localhost:8080/UploadFileServlet";

        HttpClient httpclient = new DefaultHttpClient();
        try {
            HttpPost httppost = new HttpPost(uploadUrl);

            FileBody fileBody = new FileBody(new File(filePath));

            HttpEntity reqEntity = MultipartEntityBuilder.create()
                    .addPart("file", fileBody)
                    .build();

            httppost.setEntity(reqEntity);

            System.out.println("executing request " + httppost.getRequestLine());
            HttpResponse response = httpclient.execute(httppost);
            HttpEntity resEntity = response.getEntity();

            System.out.println("----------------------------------------");
            System.out.println(response.getStatusLine());
            if (resEntity != null) {
                System.out.println("Response content length: " + resEntity.getContentLength());
            }
            EntityUtils.consume(resEntity);
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            httpclient.getConnectionManager().shutdown();
        }
    }
}

这个代码使用了Apache Httpclient库来完成文件上传，需要注意的是文件上传的地址需要根据实际情况修改。如果您有任何问题，可以随时问我。