Simple crawler download site content from a specific address

Http01app.java
1. Using multi-threaded, IO stream, net (network package)

Package main;
import java.io.*;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import Java.net.URL;
import java.net.URLConnection;
/**
* Created by lxj-pc on 2017/6/27.
 */
Public class Http01app {
Public static void Main (string[] args) {
String url = "http://tuijian.hao123.com:80/index.html";
//start thread to download HTML content at the specified location
New Thread (new Downloadhtmltask (URL)). Start ();
//Download the specified HTML content and exist d://html/hao123.html
    }

Static class Downloadhtmltask implements Runnable {
private String URL;
String fileName = "hao123.html";
String Dirpath = "D:/LXJ";

Public downloadhtmltask (String url) {

this.url = URL;
        }

@Override
Public void Run () {
//download URL specified HTML web page content
try {
url htmlurl = new URL (URL);
//Open Network resource connection
try {
URLConnection urlconnection = htmlurl.openconnection ();//.filed
HttpURLConnection conn = (httpurlconnection) urlconnection;
//Get read stream of network resource
InputStream is = Conn.getinputstream ();
//Determine if the network resource response is successful
if (conn.getresponsecode () = =) {

//Memory stream Bytearrayoutputstream
Bytearrayoutputstream BAOs = new Bytearrayoutputstream ();

byte[] buffer = new BYTE[20 * 1024];//maximum memory size 20k per read, buffer size
int len =-1;//byte length per read

//Start reading network data
//Check the progress of file download
//1. Getting the total length of network resources
int contentlength = Conn.getcontentlength ();
//2. Declaring the currently read resource length, accumulating Len
int curlen = 0;

While (len = is.read (buffer))! =-1) {
//reads read data to the memory stream
baos.write (buffer, 0, Len);

//3. Calculating download Progress
Curlen + = len;
System.out.println (Curlen + "" + contentlength);
//4. Calculating download Progress
int p = curlen/contentlength;
System.out.println ("Download progress" + p + "%");
                        }
//Download complete to get the data in the memory stream
byte[] bytes = Baos.tobytearray ();
//Convert byte array to string and print to console
//"Hello". GetBytes (); Zifu->zijie
string htmlcontent = new String (bytes, "Utf-8");
writerfile (htmlcontent, Dirpath, fileName);//member method below
System.out.println (htmlcontent);
//System.out.println (htmlcontent);
}} catch (IOException e) {
e.printstacktrace ();
                }
} catch (Malformedurlexception e) {
e.printstacktrace ();
            }


        }

//Store files in a file of the specified path
private void Writerfile (String htmlcontent, String Dirpath, String fileName) {
file dir = new file (Dirpath);

FileWriter FileWriter = null;
try {
fileWriter = new FileWriter (New File (dir, fileName));
} catch (IOException e) {
e.printstacktrace ();
            }
try {
Filewriter.write (htmlcontent);
} catch (IOException e) {
e.printstacktrace ();
            }
try {
filewriter.close ();
} catch (IOException e) {
e.printstacktrace ();
            }


        }
    }
Public static void OutputFile (String content,string dirpath,string fileName) {
file Dir=new file (dirpath);
try {
FileOutputStream fileoutputstream=new FileOutputStream (New File (Dir,filename));
Fileoutputstream.write (content.getbytes ("Utf-8"));
fileoutputstream.close ();
} catch (IOException e) {
e.printstacktrace ();
        }
    }
}

Simple crawler download site content from a specific address