HttpClient上传下载Demo

importorg.apache.http.Consts;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpGet;
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.entity.mime.content.StringBody;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.CharsetUtils;
import org.apache.http.util.EntityUtils;
import org.apache.http.entity.mime.content.FileBody;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.nio.charset.Charset;
import java.text.ParseException;

public class HttpClient {
    /**
     * 上传文件
     * @throws ParseException
     * @throws IOException
     */
    public static void postFile() throws ParseException, IOException{
        CloseableHttpClient httpClient = HttpClients.createDefault();
        try {
            // 要上传的文件的路径
            String filePath = new String("D:/ceshi.png");
            // 把一个普通参数和文件上传给下面这个地址 是一个servlet
            HttpPost httpPost = new HttpPost(
                    "http://localhost:8080/xxx/xxx.action");
            // 把文件转换成流对象FileBody
            File file = new File(filePath);
            FileBody bin = new FileBody(file);
            StringBody uploadFileName = new StringBody(
                    "把我修改成文件名称", ContentType.create(
                    "text/plain", Consts.UTF_8));
            //以浏览器兼容模式运行，防止文件名乱码。
            HttpEntity reqEntity = MultipartEntityBuilder.create().setMode(HttpMultipartMode.BROWSER_COMPATIBLE)
                    .addPart("uploadFile", bin) //uploadFile对应服务端类的同名属性<File类型>
                    .addPart("uploadFileName", uploadFileName)//uploadFileName对应服务端类的同名属性<String类型>
                    .setCharset(CharsetUtils.get("UTF-8")).build();

            httpPost.setEntity(reqEntity);

            System.out.println("发起请求的页面地址 " + httpPost.getRequestLine());
            // 发起请求 并返回请求的响应
            CloseableHttpResponse response = httpClient.execute(httpPost);
            try {
                System.out.println("----------------------------------------");
                // 打印响应状态
                System.out.println(response.getStatusLine());
                // 获取响应对象
                HttpEntity resEntity = response.getEntity();
                if (resEntity != null) {
                    // 打印响应长度
                    System.out.println("Response content length: "
+ resEntity.getContentLength());
                    // 打印响应内容
                    System.out.println(EntityUtils.toString(resEntity,
                            Charset.forName("UTF-8")));
                }
                // 销毁
                EntityUtils.consume(resEntity);
            } finally {
                response.close();
            }
        } finally {
            httpClient.close();
        }
    }
    //下载
    public static void getFile()
            throws ClientProtocolException, IOException {
        // 生成一个httpclient对象
        CloseableHttpClient httpclient = HttpClients.createDefault();
        HttpGet httpget = new HttpGet("http://www.baidu.com/img/bd_logo1.png");
        HttpResponse response = httpclient.execute(httpget);
        HttpEntity entity = response.getEntity();
        InputStream in = entity.getContent();
        File file = new File("D:\\ceshi.png");
        try {
            FileOutputStream fout = new FileOutputStream(file);
            int l = -1;
            byte[] tmp = new byte[1024];
            while ((l = in.read(tmp)) != -1) {
                fout.write(tmp, 0, l);// 注意这里如果用OutputStream.write(buff)的话，图片会失真，大家可以试试
            }
            fout.flush();
            fout.close();
        } finally {
            // 关闭低层流。
            in.close();
        }
        httpclient.close();
    }
    public static void main(String[] args) throws IOException {
        HttpClient.getFile();
        System.out.println("done!");
    }
}