java从接口获取下载地址，然后下载文件并保存到指定目录
1.java代码，结构如下入
1.pom.xml文件
4.0.0
tcl.down.url
downurl
1.0-SNAPSHOT
net.sf.json-lib
json-lib
2.4
jdk15
org.apache.httpcomponents
httpclient
4.5.5
org.springframework.boot
spring-boot-maven-plugin
downurl.Iputil
repackage
2. 通过此数据建立实体类
作用：定义json封装的bean对象
package downurl;
import java.util.List;
public class JsonBean {
private String status;
private String msg;
private DataBean data;
public String getStatus() {
return status;
}
public void setStatus(String status) {
this.status = status;
}
public String getMsg() {
return msg;
}
public void setMsg(String msg) {
this.msg = msg;
}
public DataBean getData() {
return data;
}
public void setData(DataBean data) {
this.data = data;
}
public static class DataBean {
private List list;
public List getList() {
return list;
}
public void setList(List list) {
this.list = list;
}
}
public static class TuplesBean {
private String activeDate;
private String downloadUrl;
public TuplesBean() {
}
public String getActiveDate() {
return activeDate;
}
public void setActiveDate(String activeDate) {
this.activeDate = activeDate;
}
public String getDownloadUrl() {
return downloadUrl;
}
public void setDownloadUrl(String downloadUrl) {
this.downloadUrl = downloadUrl;
}
}
}
3.发送post请求类
package downurl;
import net.sf.json.JSONObject;
import org.apache.http.HttpEntity;
import org.apache.http.ParseException;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.message.BasicHeader;
import org.apache.http.protocol.HTTP;
import org.apache.http.util.EntityUtils;
import java.io.IOException;
import java.util.HashMap;
public class JsonPost {
/**
* 发送post请求
* @param url 路径
* @param jsonObject 参数(json类型)
* @param encoding 编码格式
* @return
* @throws ParseException
* @throws IOException
*/
public static String send(String url, JSONObject jsonObject, String encoding) throws ParseException, IOException {
String body = "";
//创建httpclient对象
CloseableHttpClient client = HttpClients.createDefault();
//创建post方式请求对象
HttpPost httpPost = new HttpPost(url);
//装填参数
StringEntity s = new StringEntity(jsonObject.toString(), "utf-8");
s.setContentEncoding(new BasicHeader(HTTP.CONTENT_TYPE,
"application/json"));
//设置参数到请求对象中
httpPost.setEntity(s);
System.out.println("请求地址："+url);
// System.out.println("请求参数："+nvps.toString());
//设置header信息
//指定报文头【Content-type】、【User-Agent】
// httpPost.setHeader("Content-type", "application/x-www-form-urlencoded");
httpPost.setHeader("Content-type", "application/json");
httpPost.setHeader("User-Agent", "Mozilla/4.0 (compatible; MSIE 5.0; Windows NT; DigExt)");
//执行请求操作，并拿到结果（同步阻塞）
CloseableHttpResponse response = client.execute(httpPost);
//获取结果实体
HttpEntity entity = response.getEntity();
if (entity != null) {
//按指定编码转换结果实体为String类型
body = EntityUtils.toString(entity, encoding);
}
EntityUtils.consume(entity);
//释放链接
response.close();
return body;
}
public static void main(String[] args) throws IOException {
// post参数封装为map（map里面可以存map）
HashMap params = new HashMap<>();
params.put("date", "20200630");
params.put("typeId", "huannet_active_info");
HashMap map = new HashMap<>();
map.put("key", "dafdfawf=q8");
map.put("id", "dsdafa");
map.put("pageNum", "0");
map.put("pageSize", "1000");
map.put("params", params);
JSONObject jsonObject = JSONObject.fromObject(map);
// System.out.println(jsonObject);
String url = "http://dc-o.web.da/da/dsa/request";
// System.out.println(send(url, jsonObject, "UTF-8"));
}
}
4.下载文件并保存到目录
package downurl;
import java.io.*;
import java.net.HttpURLConnection;
import java.net.URL;
public class DownUrl {
/**
* @从制定URL下载文件并保存到指定目录
* @param filePath 文件将要保存的目录
* @param method 请求方法，包括POST和GET
* @param url 请求的路径
* @return
*/
public static File saveUrlAs(String url,String filePath,String method){
//System.out.println("fileName---->"+filePath);
//创建不同的文件夹目录
File file=new File(filePath);
//判断文件夹是否存在
if (!file.exists())
{
//如果文件夹不存在，则创建新的的文件夹
file.mkdirs();
}
FileOutputStream fileOut = null;
HttpURLConnection conn = null;
InputStream inputStream = null;
try
{
// 建立链接
URL httpUrl=new URL(url);
conn=(HttpURLConnection) httpUrl.openConnection();
//以Post方式提交表单，默认get方式
conn.setRequestMethod(method);
conn.setDoInput(true);
conn.setDoOutput(true);
// post方式不能使用缓存
conn.setUseCaches(false);
//连接指定的资源
conn.connect();
//获取网络输入流
inputStream=conn.getInputStream();
BufferedInputStream bis = new BufferedInputStream(inputStream);
//判断文件的保存路径后面是否以/结尾
if (!filePath.endsWith("/")) {
filePath += "/";
}
//写入到文件（注意文件保存路径的后面一定要加上文件的名称）
fileOut = new FileOutputStream(filePath+url.substring(url.lastIndexOf("/")+1,url.lastIndexOf("?")));
BufferedOutputStream bos = new BufferedOutputStream(fileOut);
byte[] buf = new byte[4096];
int length = bis.read(buf);
//保存文件
while(length != -1)
{
bos.write(buf, 0, length);
length = bis.read(buf);
}
bos.close();
bis.close();
conn.disconnect();
} catch (Exception e)
{
e.printStackTrace();
System.out.println("抛出异常！！");
}
return file;
}
/**
* @param args
*/
public static void main(String[] args)
{
String photoUrl = "http://dasfda.oss-cn-hangzhou.aliyuncs.com/logclean/dafa/user_info2/date%3D2020-06-01/part-00003-07477e29-b6da-40b5-8c09-af5c4067606f-c000.snappy.parquet?Expires=1594915200&OSSAccessKeyId=dafa&Signature=4qATSNRtaW4u3TQsjPb%2B73KzqkM%3D"; //文件URL地址
// String fileName = photoUrl.substring(photoUrl.lastIndexOf("/")); //为下载的文件命名
String fileName = "/tupian";
String filePath = "e:"; //保存目录
File file = saveUrlAs(photoUrl, filePath + fileName,"GET");
}
}
5.主类
package downurl;
import net.sf.json.JSONArray;
import net.sf.json.JSONObject;
import java.io.*;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.*;
public class Iputil {
//存储执行日期
static String date;
public static void main(String[] args) throws ParseException {
//获取当前执行日期的前一天
Calendar calendar = Calendar.getInstance();
SimpleDateFormat sj = new SimpleDateFormat("yyyyMMdd");
calendar.add(Calendar.DATE, -1);//当前时间减去一年，即一年前的时间
String str = sj.format(calendar.getTime());
date = str;
// 封装post参数
HashMap params = new HashMap<>();
params.put("date", date);
params.put("typeId", "vgavadva");
HashMap map = new HashMap<>();
map.put("key", "fafege=q8");
map.put("id", "fagfa");
map.put("pageNum", "0");
map.put("pageSize", "1000");
map.put("params", params);
//将map转为json对象
JSONObject jsonObject = JSONObject.fromObject(map);
Iputil iputil = new Iputil();
// 执行run方法
iputil.run(jsonObject);
}
public void run(JSONObject params) {
JsonBean jsonBean = new JsonBean();
try {
JSONObject jsonObject = JSONObject.fromObject(params);
JsonPost jsonpost = new JsonPost();
System.out.println(jsonObject);
String url = "http://dc-o.web.leiniao.com/dafadaf/open/request";
// 调用send方法，发送post请求，获取数据
String urlString = jsonpost.send(url, params, "UTF-8");
JSONObject json = JSONObject.fromObject(urlString);//大括号object 字符串string 数组list
// 封账json对象数据
jsonBean.setStatus(json.optString("status"));
jsonBean.setMsg(json.optString("msg"));
JSONObject dataObj = json.optJSONObject("data");
JsonBean.DataBean data = new JsonBean.DataBean();
JSONArray tuplesArray = dataObj.optJSONArray("result");
List tuplesBeansList = new ArrayList<>();
for (int i = 0; i < tuplesArray.size(); i++) {
JSONObject tuplesObj = tuplesArray.optJSONObject(i);
// System.out.println(tuplesObj.getString("downloadUrl"));
if (tuplesObj.toString().contains("part")) {
System.out.println(tuplesObj.getString("downloadUrl"));
JsonBean.TuplesBean tuplesBean = new JsonBean.TuplesBean();
tuplesBean.setActiveDate(tuplesObj.getString("activeDate"));
tuplesBean.setDownloadUrl(tuplesObj.getString("downloadUrl"));
tuplesBeansList.add(tuplesBean);
}
}
data.setList(tuplesBeansList);
jsonBean.setData(data);
} catch (
IOException e) {
e.printStackTrace();
}//get数据
try {
DownUrl downurl = new DownUrl();
// 循环调用saveUrlAs方法，将文件下载到指定目录
for (int i = 0; i < jsonBean.getData().getList().size(); i++) {
String photoUrl = jsonBean.getData().getList().get(i).getDownloadUrl(); //文件URL地址
// String fileName = photoUrl.substring(photoUrl.lastIndexOf("/")); //为下载的文件命名
// System.out.println(photoUrl);
SimpleDateFormat formatter = new SimpleDateFormat("yyyyMMdd");
formatter.setLenient(false);
Date newDate = formatter.parse(date);
formatter = new SimpleDateFormat("yyyy-MM-dd");
String filedir = formatter.format(newDate);
String fileName = "/lbird/" + filedir;
String filePath = "/root"; //保存目录
File file = downurl.saveUrlAs(photoUrl, filePath + fileName, "GET");
}
} catch (
Exception e) {
e.printStackTrace();
}
}
}
2.将打好的jar上传到服务器
1.打包步骤
点击idea的Maven后，点击package。如下图
2.执行打包后的jar
java -jar downurl-1.0-SNAPSHOT.jar