it can be done with base java libraries, but you should get that package anyway it's super convenient, and why reinvent the wheel when you can write a program in 20 lines of code lol
// Using Commons IO library
// Available at http://commons.apache.org/io/download_io.cgi
import org.apache.commons.io.FileUtils;
import org.apache.commons.io.FilenameUtils;
import java.io.BufferedReader;
import java.io.File;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.URL;
public class JSP_Request_2 {
public static void main(String[] args) throws IOException {
//STARTO
System.out.println("start");
//Make sure this directory exists if it doesn't change the path to wherever you want to put the files
String directory = "C:\\Users\\user\\IdeaProjects\\JSP_Request_2\\";
//Make a URL out of the link to the page you wanted
URL input = new URL("http://www.artofproblemsolving.com/wiki/index.php?title=Mathematics_competitions_resources#Free");
//Make a reader to scan the html of it
BufferedReader in = new BufferedReader(new InputStreamReader(input.openStream()));
//Make a string to hold the values you read from each line
String inputLine;
//Read each line of the html
while ((inputLine = in.readLine()) != null) {
//find a string that is unique to the html that looks like a good starting point
//read through the html til you find it
if (inputLine.contains("Problem Sets</span></h3>")) {
//find a string unique to the html that is in your last read line that will stop the program
while (!inputLine.contains("Other Geometry")) {
//set your string = next line
inputLine = in.readLine();
//split the line up into seperate strings delimited by a "
String words[] = inputLine.split("[\"]");
//ignore the <ul>s and </ul> lines
if(words.length>5) {
//cool utility you get with commons to grab the filename, can be done with base io library, but fuck a bunch of parsing
String file = FilenameUtils.getBaseName(words[5]);
//print the filename of the file you want to download
System.out.println("Downloaded : " + file);
//download the file (to the directory we made earlier + the file name + with the extension .pdf because for some reason not all your links have the extension,
// words[5] is where your file link is in the split
download(directory + FilenameUtils.getBaseName(words[5])+".pdf",words[5]);
}
}
}
}
//close the stream
in.close();
//DONE
System.out.println("done");
}
//commons ftw this method is probably like 15 lines with java io utils
public static void download(String fileName, String fileUrl)throws IOException {
FileUtils.copyURLToFile(new URL(fileUrl), new File(fileName));
}
}