[Java知识库] java模拟请求下载文件

开发: C++知识库 Java知识库 JavaScript Python PHP知识库人工智能区块链大数据移动开发嵌入式开发工具数据结构与算法开发测试游戏开发网络协议系统运维
教程: HTML教程 CSS教程 JavaScript教程 Go语言教程 JQuery教程 VUE教程 VUE3教程 Bootstrap教程 SQL数据库教程 C语言教程 C++教程 Java教程 Python教程 Python3教程 C#教程
数码: 电脑笔记本显卡显示器固态硬盘硬盘耳机手机 iphone vivo oppo 小米华为单反装机图拉丁

-> Java知识库 -> java模拟请求下载文件 -> 正文阅读

[Java知识库]java模拟请求下载文件

首先添加依赖

		<dependency>
            <groupId>commons-httpclient</groupId>
            <artifactId>commons-httpclient</artifactId>
            <version>3.1</version>
        </dependency>

一般下载文件都是Get请求，这里需要设置Cookie

package com.download.demo;

import org.apache.commons.httpclient.HttpClient;
import org.apache.commons.httpclient.HttpConnectionManager;
import org.apache.commons.httpclient.SimpleHttpConnectionManager;
import org.apache.commons.httpclient.methods.GetMethod;
import org.apache.commons.httpclient.params.HttpConnectionManagerParams;

import java.io.File;
import java.io.FileOutputStream;
import java.io.InputStream;

public class DownUtils {
    public static void main(String[] args) {
        download(1, 2, 3, "param4");
    }

    private static void download(long param1, long param2, int param3, String param4){
        String uri  =String.format("http://www.xxx.com/user/statistics/association/export?start=%d&end=%d&ruleTemplateCode=sell_purchase_statistics&ruleId=%d", param1, param2, param3);
        HttpConnectionManager manager = new SimpleHttpConnectionManager();
        HttpConnectionManagerParams params = new HttpConnectionManagerParams();
        params.setConnectionTimeout(5000);
        params.setSoTimeout(5000);
        manager.setParams(params);
        HttpClient client = new HttpClient(manager);
        GetMethod method = new GetMethod(uri);
        method.addRequestHeader("Cookie", "token=MzsyOzgyNDUyOzEwMDAwNzoxNjUzMzU3MzQ5NjI2OmM3ZWQ5ZDk0Y2I4YmFkNjMyYWY4MDZlZGM1YzYzZTlh;");
        try{
            client.executeMethod(method);
            int statusCode = method.getStatusCode();
            if (statusCode == 200) {
                //保存文件
                InputStream in = method.getResponseBodyAsStream();
                File file = new File("D:/temp2/" + param1+ "-" + param2 + "-" +param3);//这里为存储路径/xx/xx..

                FileOutputStream fout = new FileOutputStream(file);
                int a = -1;
                byte[] tmp = new byte[1024];
                while ((a = in.read(tmp)) != -1) {
                    fout.write(tmp, 0, a);
                }
                fout.flush();
                fout.close();
                in.close();
            }
        }catch (Exception e){
            e.printStackTrace();
        }finally {
            method.releaseConnection();
        }
    }
}