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JDA - VoiceChannel#getMembers() isn't returning voice users

I want to iterate through my discord's voices channels and get their members.
But my code (below) isn't working as expected.
for (VoiceChannel voiceChannel : event.getJDA().getGuildById(Config.guildId).getVoiceChannelCache()) {
System.out.println("-> " + voiceChannel.getName() + " -->> " + voiceChannel.getMembers().size());
}
However I put it after a ReadyEvent, so I don't know why it isn't working

bitcoinJ get transaction value

I downloaded a lot of blockchain data using https://bitcoin.org, I took some file and I try to analyse it with bitcoinj library.
I would like to get information from every transaction:
-who send bitcoins,
-how much,
-who receive bitcoins.
I use:
<dependency>
<groupId>org.bitcoinj</groupId>
<artifactId>bitcoinj-core</artifactId>
<version>0.15.10</version>
</dependency>
I have a code:
NetworkParameters np = new MainNetParams();
Context.getOrCreate(MainNetParams.get());
BlockFileLoader loader = new BlockFileLoader(np,List.of(new File("test/resources/blk00450.dat")));
for (Block block : loader) {
for (Transaction tx : block.getTransactions()) {
System.out.println("Transaction ID" + tx.getTxId().toString());
for (TransactionInput ti : tx.getInputs()) {
// how to get wallet addresses of inputs?
}
// this code works for 99% of transactions but for some throws exceptions
for (TransactionOutput to : tx.getOutputs()) {
// sometimes this line throws: org.bitcoinj.script.ScriptException: Cannot cast this script to an address
System.out.println("out address:" + to.getScriptPubKey().getToAddress(np));
System.out.println("out value:" + to.getValue().toString());
}
}
}
Can you share some snippet that will work for all transactions in the blockchain?

There are at least two type of transaction, P2PKH and P2SH.
Your code would work well with P2PKH, but wouldn not work with P2SH.
You can change the line from:
System.out.println("out address:" + to.getScriptPubKey().getToAddress(np));
to:
System.out.println("out address:" + to.getAddressFromP2PKHScript(np)!=null?to.getAddressFromP2PKHScript(np):to.getAddressFromP2SH(np));
The API of Bitcoin says the methods getAddressFromP2PKHScript() and getAddressFromP2SH() are deprecated, and I have not find suitable method.
However, P2SH means "Pay to Script Hash", which means it could contain two or more public keys to support multi-signature. Moreover, getAddressFromP2SH() returns only one address, perhaps this is the reason why it is deprecated.
I also wrote a convinient method to check the inputs and outputs of a block:
private void printCoinValueInOut(Block block) {
Coin blockInputSum = Coin.ZERO;
Coin blockOutputSum = Coin.ZERO;
System.out.println("--------------------Block["+block.getHashAsString()+"]------"+block.getPrevBlockHash()+"------------------------");
for(Transaction tx : block.getTransactions()) {
Coin txInputSum = tx.getOutputSum();
Coin txOutputSum = tx.getOutputSum();
blockInputSum = blockInputSum.add(txInputSum);
blockOutputSum = blockOutputSum.add(txOutputSum);
System.out.println("Tx["+tx.getTxId()+"]:\t" + txInputSum + "(satoshi) IN, " + txOutputSum + "(satoshi) OUT.");
}
System.out.println("Block total:\t" + blockInputSum + "(satoshi) IN, " + blockOutputSum + "(satoshi) OUT. \n");
}

Minecraft Chat Message Replacement

I am making a permissions plugin, and want to replace the name of a player with their rank tag. For this, I have the following code:
public void playerChat(AsyncPlayerChatEvent e) {
Player target = e.getPlayer();
String message = e.getMessage().replaceAll(target.getName(), colorize(rFile.getString("players." + target)) + " " + target.getName());
e.setMessage(message);
}
Whenever I send a message to chat, it appears like it would normally.
What am I doing wrong here?
Additionally, I am using a config file (cFile) and a ranks.yml file (rFile).

First off, make sure you include the #EventHandler annotation.
#EventHandler
public void playerChat(AsyncPlayerChatEvent e) {
[...]
}
Next, check if the listener is registered in your onEnable()method.
getServer().getPluginManager().registerEvents(new YourListener(...), this);
(Replace the YourListener with this in case it's your main class)
Finally, as Luftbaum said, use AsyncPlayerChatEvent#setFormat within the event.
Example Usage:
e.setFormat(colorize(rFile.getString("players." + target)) + ": " + e.getMessage());
Edit:
In order to translate color codes such as '&3' to Bukkit's ChatColor format, you can use the ChatColor#translateAlternativeColorCodes method.
ChatColor.translateAlternateColorCodes('&', stringThatContainsCodes);

Useevent.setFormat(playerRank + ": " + event.getMessage());
This basically formats the message to be the way you want. You can use ChatColor to do colors. Also make sure you have #EventHandler.

Parrot AR.Drone 2.0 - JavaDrone (Get the drone details E.G. Battery Level, Altitude, Speed etc)?

I am working on Parrot AR. Drone project. The libraries are downloaded and implemented in this project from JavaDrone website (https://code.google.com/p/javadrone/downloads/list). However, although I did included the all the correct libraries and make the right class call to get the method, it still cannot return me the correct information. All the results returned appeared to be "false". Any idea what happening on this code? Please help me :(
So what I did is I have 2 buttons : (i) connect (ii) take off buttons. The Connect button function is for establish connection to drone while Take off button is used for make the drone fly move a bit and return me the drone's NAV navigation data. Sadly all the returned NAV data appears not working.
Note : This code is working fine upon code compilation. But it just cannot return me the correct & valid NAV data from drone.
private void jButtonConnectActionPerformed(java.awt.event.ActionEvent evt) {
System.out.println("Connect?");
drone = new ARDrone();
data = new NavData();
drone.playLED(10,10,10);
drone.connect();
drone.clearEmergencySignal();
System.err.println("Ready to connect!!");
// Wait until drone is ready
drone.waitForReady(CONNECT_TIMEOUT);
System.err.println("Drone State: " + drone.getState());
// do TRIM operation
drone.trim();
System.err.println("Congratulation! You have connected to Drone!");
System.out.println("You can issue flight commands now!");
batteryStatus.setText("0" + "%");
batteryStatus.setForeground(Color.ORANGE);
batteryStatus.setText("" + data.getBattery());
}
private void jButtonTakeOffActionPerformed(java.awt.event.ActionEvent evt) {
System.err.println("Current Drone State : " + drone.getState().toString());
System.err.println("Taking off");
drone.takeOff();
Thread.sleep(4000);
System.err.println("**********\nMOVE\n**********");
drone.move(0.0f, 150.5f, 500.0f, 0.0f);
Thread.sleep(1000);
System.err.println("******************************************");
System.err.println("Drone Infomation");
System.err.println("Battery Too High ? " + data.isBatteryTooHigh());
System.err.println("Battery Too Low ? " + data.isBatteryTooLow());
System.err.println("Drone Flying ? " + data.isFlying());
System.err.println("Control Received ? " + data.isControlReceived());
System.err.println("Motor Down ? " + data.isMotorsDown());
System.err.println("Not Enough Power ?" + data.isNotEnoughPower());
System.err.println("Trim Received ? " + data.isTrimReceived());
System.err.println("Trim Running? " + data.isTrimRunning());
System.err.println("Trim succeded? " + data.isTrimSucceeded());
System.err.println("PIC Number OK? "+ data.isPICVersionNumberOK());
System.err.println("******************************************");
Thread.sleep(5000);
drone.sendAllNavigationData();
drone.land();
}
Output :
******************************************
Drone Infomation
Battery Life: 0.0%
Battery Too High ? false
Battery Too Low ? false
Drone Flying ? false
Control Received ? false
Motor Down ? false
Not Enough Power ?false
Trim Received ? false
Trim Running? false
Trim succeded? false
PIC Number OK? false
********************************************
Update:
What I did was followed John's suggestion. I did implemented all the neccessary methods and NavDataListener for getting the NavData from drone.
import com.codeminders.ardrone.ARDrone;
import com.codeminders.ardrone.ARDrone.VideoChannel;
import com.codeminders.ardrone.NavData;
import com.codeminders.ardrone.NavDataListener;
public class arDrone extends javax.swing.JFrame implements Runnable, NavDataListener{
public ARDrone drone;
public NavData data = new NavData();
public arDrone(String text) {
//FreeTTS speech text
this.text=text;
}
public arDrone() {
initComponents();
setIcon();
initDrone();
}
private void initDrone() {
try {
drone = new ARDrone();
data = new NavData();
drone.addNavDataListener(this);
} catch (UnknownHostException ex) {
System.err.println(ex);
return;
}
}
public void navDataReceived(NavData nd) {
System.err.println("Testing navDataReceived is running...");
updateBatteryStatus(nd.getBattery());
this.flying.set(nd.isFlying());
}
private void updateBatteryStatus(final int value) {
java.awt.EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
batteryStatus.setText(value + "%");
if (value < 15) {
batteryStatus.setForeground(Color.RED);
} else if (value < 50) {
batteryStatus.setForeground(Color.ORANGE);
} else {
batteryStatus.setForeground(Color.GREEN);
}
}
});
}

The problem is that you are not doing anything to actually get navdata. You can't just create a NavData object and hope it gets filled in with valid data--It won't.
You need to use the com.codeminders.ardrone.NavDataListener interface.
Implement the NavDataListener interface, and the
navDataReceived method.
Add your listener using the ARDrone
method addNavDataListener.
In your navDataRecieved method
you will receive a NavData object with valid telemetry data.

Do you set the Drone IP address? According to sources the default IP for the drone is 192.168.1.1.
You can call another constructor to set the IP:
drone = new ARDrone(InetAddress.getByName("xxx.xxx.xxx.xxx"));
replace xxx.xxx.xxx.xxx with the actual drone IP.

Server does not respond directly to my commands

First of all, I'll admit I am new to this and I've probably just forgotten to set an option somewhere to the correct variable, but my Googling has failed me and I have no idea what to do, so I was hoping to get some help.
I have based this on the SecureChat example, it can be located here: http://netty.io/docs/unstable/xref/org/jboss/netty/example/securechat/package-summary.html
And the difference I have made, have been only in the SecureChatServerHandler. More precisely in the messageRecieved block:
#Override
public void messageReceived(ChannelHandlerContext ctx, MessageEvent e) throws Exception {
// Convert the message to a string
String request = (String) e.getMessage();
System.out.println("Message recieved: " + request);
if (request.equalsIgnoreCase("clients")) {
channels.write("We currently have: " + channels.size() + " clients");
} else if (request.toLowerCase().equals("koko"))
for (Channel c : channels) {
if (c == e.getChannel())
c.write("HELLO WORLD");
}
else {
// Then send it to all channels, but the current one.
for (Channel c : channels)
if (c != e.getChannel())
c.write("[" + e.getChannel().getRemoteAddress() + "] " + request + "\n");
else
c.write("[you] " + request + "\n");
}
if (request.equalsIgnoreCase("bye"))
e.getChannel().close();
}
If I send a normal message that is getting broadcasted, everything works. But if I send a command, like clients or koko, I get no response, until I press enter again and send a empty message. First then I get the response back.
C:\Device Manager\Application Server\Examp
les\SecureChat\SecureChatClient\bin>java -jar client.jar 127.0.0.1 8080
UNKNOWN SERVER CERTIFICATE: CN=securechat.example.netty.gleamynode.net, OU=Contr
ibutors, O=The Netty Project, L=Seongnam-si, ST=Kyunggi-do, C=KR
Welcome to Electus secure chat service!
Your session is protected by TLS_DHE_RSA_WITH_AES_128_CBC_SHA cipher suite
You are the 1th user
koko<ENTER>
<PRESS ENTER AGAIN>
HELLO WORLD[you]
clients<ENTER>
<AND ENTER ONCE AGAIN>
We currently have: 1 clients[you]
What I don't understand, and don't want, is the -pressing of enter button twice- thing. It seems highly inlogical and it is irritating. I didn't have these problem with the Telnet Example.
Thank you for your time.
Regards,
Aldrian.

This is one of those humiliating times where you just forgot one small detail, and that messes everything up.
if (request.equalsIgnoreCase("clients")) {
channels.write("We currently have: " + channels.size() + " clients /n"); // Forgot /n here
} else if (request.toLowerCase().equals("koko"))
for (Channel c : channels) {
if (c == e.getChannel())
c.write("HELLO WORLD /n"); // <- Forgot /n here as well
}