java模拟请求下载文件

首先添加依赖

		<dependency>
            <groupId>commons-httpclientgroupId>
            <artifactId>commons-httpclientartifactId>
            <version>3.1version>
        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();
        }
    }
}