I've been trying to find a line and print it out on this website: http://www.easports.com/player-hub/360/Its+McDoom
Right now it prints out everything on the website, but I cannot find the line I am looking for. I am trying to print out "H2h Skill Points: 1053", but I cannot find anything like that in the console.
I only really want it to print that 1 line, not the whole thing, but I can't even find it.
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.net.URL;
import java.net.URLConnection;
public class ElectronicArtsStatHub {
/**
* #param args
*/
public static void main (String[] args) throws Exception{
URL oracle = new URL("http://www.easports.com/player-hub/360/Its+McDoom");
URLConnection yc = oracle.openConnection();
BufferedReader in = new BufferedReader(new InputStreamReader(
yc.getInputStream()));
String inputLine;
while ((inputLine = in.readLine()) != null) {
System.out.println(inputLine);
}
in.close();
}
}
The first problem is that the information your trying to find isn't actually in the data you are currently outputting.
When you open the page in your browser you get the main page elements but then your browser then runs some Javascript code which presumably uses AJAX to get the stats and fill in the table.
The URLConnection receives the same data that your browser initially does and does not execute the Javascript so if you check your output that data your looking for isn't actually there at all.
Possible solutions include finding a different source for this data or executing the Javascript in Java possibly by using HTMLUnit
There may be some helpful infomation on this related question
Related
I'm writing a discord bot using the nyxx library and want use dynamic file import for load command info and handler. But, after 5 hours of searching with Google, I didn't find anything to help me do that.
In Node.js, I can use require() or import() for it: Does the dart have something like that?
A small code snippet, showing what I want do:
this.commands = new Collection();
fs.readdirSync('./src/commands').filter(( f ) => f.endsWith( '.js' )).forEach((file) => {
const command = require(`../commands/${file}`);
this.commands.set( command.info.name, command );
});
Is it possible to do this or not? (I don't like to write many imports for commands and register it in lib.)
You can in theory use Isolate.spawnUri to spawn external Dart programs to run in its own Isolate instances that can then communicate back to the main program using SendPort.
It does, however, come with some limitations. E.g. it is very limited what types of objects you can send though SendPort when using spawnUri since the two programs does not share any type information (compared to Isolate.spawn which does allow you to send your own custom types). The documented types you can send can be found here:
Null
bool
int
double
String
List or Map (whose elements are any of these)
TransferableTypedData
SendPort
Capability
https://api.dart.dev/stable/2.17.6/dart-isolate/SendPort/send.html
But it does allow us to make some kind of protocol and you can create some helper class around this to handle the conversion of a known object structure into e.g. Map<String, Object>.
A small example that works with Dart VM would be:
Your command implemented as: command.dart
import 'dart:isolate';
void main(List<String> arguments, Map<String, Object> message) {
final userName = message['username'] as String;
final sendPort = message['port'] as SendPort;
sendPort.send('Hi $userName. '
'You got a message from my external command program!');
}
Your server that calls your command: server.dart
import 'dart:isolate';
void main() {
final recievePort = ReceivePort();
recievePort.listen((message) {
print('Got the following message: $message');
recievePort.close();
});
Isolate.spawnUri(Uri.file('command.dart'), [], {
'username': 'julemand101',
'port': recievePort.sendPort,
});
}
If running this with: dart server.dart you, hopefully, get:
Got the following message: Hi julemand101. You got a message from my external command program!
If you want to compile your application, you can do so by doing the following. You need to compile the command.dart, since a compiled Dart program does not understand how to read Dart code.
dart compile exe server.dart
dart compile aot-snapshot command.dart
You should here change Uri.file('command.dart') to Uri.file('command.aot') since the file-extension for aot-snapshot are .aot.
If everything works, you should be able to see:
> .\server.exe
Got the following message: Hi julemand101. You got a message from my external command program!
I need to determine the browser timezone. I tried to follow this post but does not work (Vaadin 20). Here is my code:
ZoneId myZoneId;
...
UI.getCurrent().getPage().retrieveExtendedClientDetails(extendedClientDetails -> {
myZoneId = ZoneId.of(extendedClientDetails.getTimeZoneId());
});
// here myZoneId has value null.
So I tried to do it myself, initially simply displaying it.
UI.getCurrent().getPage()
.executeJs("return Intl.DateTimeFormat().resolvedOptions().timeZone;")
.then(value -> Notification.show(value.asString()));
It works and I read "Europe/Rome", but its value does not seem something that I can map to a ZoneId in Java.
I could explore a little more the Javascript zone object but I also was unable to find where my code actually went to debug it with chrome debugger (there is no mention in Vaadin doc where the code goes).
I could work on the returned value and try to interpret it but I would like to avoid reinventing the wheel.
Do anybody has any code that works?
retrieveExtendedClientDetails is an asynchronous call, thus the result is available inside the callback and not right after firing the callback (on the place you commented).
Also, UI.getCurrent() could return null if called too soon, f.e. in a constructor.
retrieveExtendedClientDetails makes a client roundtrip the first time it is run (docs).
If already obtained, the callback is called directly. Otherwise, a client-side roundtrip will be carried out.
That means you could try to run it when initialising the UI and later you should have it ready right away after firing.
#SpringComponent
public class MyVaadinServiceInitListener implements VaadinServiceInitListener {
#Override
public void serviceInit(ServiceInitEvent event) {
event.getSource().addUIInitListener(uiEvent -> {
var ui = event.getUI();
ui.getPage().retrieveExtendedClientDetails(detail -> {});
});
}
}
Another solution is to read the zone inside the callback.
Europe/Rome is fine for Java.
You can simply call:
ZoneId.of("Europe/Rome");
Thanks to everybody!
Finally the main problem was not retrieving the time zone from the client but matching it against the list of available time zones returned by ZoneId.getAvailableZoneIds(). The fact is that there were multiple timezone for CEST (Central Europe) as well as any other country. I counted 7 for Brazil that only has 5 time zones!
Honestly I am little ignorant about time zones (world would be quite simpler if we could use only GMT and adjust our schedules accordingly). The solution was to digest the timezone list using the name. I do not know if this is right or wrong, but it is simple and works, despite the fact that if I choose CEST I do not know if it will be Rome, Berlin or whatever else. Does it matter?
Here is the complete code if somebody should one day need a
package net.cbsolution.scc.vaadin.comps;
import com.vaadin.flow.component.AttachEvent;
import com.vaadin.flow.component.ItemLabelGenerator;
import com.vaadin.flow.component.UI;
import com.vaadin.flow.component.combobox.ComboBox;
import com.vaadin.flow.data.provider.ListDataProvider;
import com.vaadin.flow.data.renderer.TemplateRenderer;
import java.time.ZoneId;
import java.time.format.TextStyle;
import java.util.*;
import java.util.stream.Collectors;
public class TimeZoneSelector extends ComboBox<ZoneId> {
private Locale locale = UI.getCurrent().getLocale();
public TimeZoneSelector() {
// Digest the timezone list
final Map<String, ZoneId> cleanMap = new HashMap<>();
ZoneId.getAvailableZoneIds().stream().map(z -> ZoneId.of(z)).forEach(z -> cleanMap.put(print(z), z));
cleanMap.values().stream().collect(Collectors.toList());
setWidth("20em");
setDataProvider(new ListDataProvider<>(cleanMap.values().stream().collect(Collectors.toList())));
setRenderer(TemplateRenderer.<ZoneId>of("<span>[[item.print]]</span>")
.withProperty("print", tz -> print(tz))
);
setItemLabelGenerator((ItemLabelGenerator<ZoneId>) item -> print(item));
}
protected String print(ZoneId zoneId) {
return zoneId.getDisplayName(TextStyle.FULL, UI.getCurrent().getLocale());
}
#Override
protected void onAttach(AttachEvent attachEvent) {
UI.getCurrent().getPage().retrieveExtendedClientDetails(details -> {
TimeZone uiTimeZone = TimeZone.getTimeZone(details.getTimeZoneId());
setValue(ZoneId.of(uiTimeZone.getID()));
});
}
}
try this
//Read the timezone and store in into the session class
if(UI.getCurrent() != null) {
UI.getCurrent().getPage().retrieveExtendedClientDetails(details -> {
// Set the time zone
TimeZone uiTimeZone = TimeZone.getTimeZone(details.getTimeZoneId());
});
};
I am currently new with javaC. I have installed JDK and set the path to make it work. I have already done several test programs and they worked.
Let's say I have a java file called Read.java and a text file called Numbers.txt
I have already set my directory to where the files are and I enter to command
javac Read.java
then
java Read < input.txt
Problem is how I can set Read.java program to receive the input.txt file?
I know you can read the file from the program itself without redirection. But I want to learn how you can read a file using redirection.
Java's main method looks something like:
public static void main(String[] args)
{
// method body
}
args is an array of parameters that the user can pass to the program - the first parameter would be args[0], the second args[1] and so on.
To receive the input text file, you can have the user type java Read input.txt. input.txt will be the first parameter, and so you can access it by using args[0] in your main method.
A simple example of command line arguments:
public static void main(String[] args)
{
String input = args[0];
System.out.println("You entered: " + input);
}
You can run this by typing java ProgramName hello, and the output will be You entered hello.
You need to read from standard input:
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
public class IORedirection {
public static void main(String[] args) throws IOException {
BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
String line;
while((line = in.readLine()) != null){
System.out.println(line);
}
}
}
> echo "hello stdin" | java IORedirection
> hello stdin
how I can set Read.java program to receive the input.txt file? I know you can read the file from the program itself without redirection. But I want to learn how you can read a file using redirection.
There are several ways to get input to your program.
This isn't about "Java", but rather what are the ways for the caller to write data to "standard input" (or "stdin"). Within any Java program, you can read stdin with System.in.
So, use System.in within your program, and then use a pipe (|) or a redirect (<). Below are two working examples from an answer I posted on a related question:
% cat input.txt | java SystemInExample.java
% java SystemInExample.java < input.txt
I have a general question on how to proper implement a logging system in dart. I can't find reliable doc on it. Is logging lib up to date ? Thx !
I think this is the simplest way to set it up
import 'package:logging/logging.dart' show Logger, Level; // every library
import 'package:quiver_log/log.dart'; // library containing main
final _log = new Logger('bwu_model.server.main'); // every library
// main
void main() {
Logger.root.level = Level.FINEST;
var appender = new PrintAppender(BASIC_LOG_FORMATTER);
appender.attachLogger(Logger.root);
// actual logging
_log.info('Pub session initialized.');
}
I've made a SAX parser for parsing XML files with a number of different tags. For performance reasons, I chose SAX over DOM. And I'm glad I did because it works fast and good. The only issue I currently have is that the main class (which extends DefaultHandler) is a bit large and not very easy on the eyes. It contains a huge if/elseif block where I check the tag name, with some nested if's for reading specific attributes. This block is located in the StartElement method.
Is there any nice clean way to split this up? I would like to have a main class which reads the files, and then a Handler for every tag. In this Tag Handler, I'd like to read the attributes for that tag, do something with them, and then go back to the main handler to read the next tag which again gets redirected to the appropriate handler.
My main handler also has a few global Collection variables, which gather information regarding all the documents I parse with it. Ideally, I would be able to add something to those collections from the Tag Handlers.
A code example would be very helpful, if possible. I read something on this site about a Handler Stack, but without code example I was not able to reproduce it.
Thanks in advance :)
I suggest setting up a chain of SAX filters. A SAX filter is just like any other SAX Handler, except that it has another SAX handler to pass events into when it's done. They're frequently used to perform a sequence of transformations to an XML stream, but they can also be used to factor things the way you want.
You don't mention the language you're using, but you mention DefaultHandler so I'll assume Java. The first thing to do is to code up your filters. In Java, you do this by implementing XMLFilter (or, more simply, by subclassing XMLFilterImpl)
import java.util.Collection;
import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.XMLFilterImpl;
public class TagOneFilter extends XMLFilterImpl {
private Collection<Object> collectionOfStuff;
public TagOneFilter(Collection<Object> collectionOfStuff) {
this.collectionOfStuff = collectionOfStuff;
}
#Override
public void startElement(String uri, String localName, String qName,
Attributes atts) throws SAXException {
if ("tagOne".equals(qName)) {
// Interrogate the parameters and update collectionOfStuff
}
// Pass the event to downstream filters.
if (getContentHandler() != null)
getContentHandler().startElement(uri, localName, qName, atts);
}
}
Next, your main class, which instantiates all of the filters and chains them together.
import java.util.ArrayList;
import java.util.Collection;
import org.xml.sax.XMLReader;
import org.xml.sax.helpers.XMLReaderFactory;
public class Driver {
public static void main(String[] args) throws Exception {
Collection<Object> collectionOfStuff = new ArrayList<Object>();
XMLReader parser = XMLReaderFactory.createXMLReader();
TagOneFilter tagOneFilter = new TagOneFilter(collectionOfStuff);
tagOneFilter.setParent(parser);
TagTwoFilter tagTwoFilter = new TagTwoFilter(collectionOfStuff);
tagTwoFilter.setParent(tagOneFilter);
// Call parse() on the tail of the filter chain. This will finish
// tying the filters together before executing the parse at the
// XMLReader at the beginning.
tagTwoFilter.parse(args[0]);
// Now do something interesting with your collectionOfStuff.
}
}