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Process does not exit when launched from Java

I am launching WebTorrent-CLI from within my Java application as a separate process. I am using zt-exec for managing the process. When WebTorrent is launched with the following command, it is supposed to exit after the file at given index (value of --select) has been downloaded.
"D:\downloadmanager\node\webtorrent.cmd" download "magnet:?xt=urn:btih:08ada5a7a6183aae1e09d831df6748d566095a10&dn=Sintel" --select 0 --out "D://nf/"
As expected, webtorrent-cli does exit after downloading 0th file when the command above is used to launch it from command line. But when I try the same from within my Java app, it completely ignores the --select option and continues downloading other files in the torrent.
Basically, when launched as a process from Java, webtorrent ignores all the options set (--select, --out or whatever). I should mention that there is nothing wrong with the library because recently I've tried replacing it with commons-exec and that solved nothing. Also, to make sure that the right command is passed while starting the process, I'm printing the command right before calling executor.start(). The command above is copied from the output retrieved from printing the command before the process starts.
This is how the process is started:
#Override
public synchronized void start() throws IOException {
if (mWasDownloadStarted || mWasDownloadFinished) return;
mExec.getCommand().listIterator().forEachRemaining(s -> {
System.out.print(s + " ");
});
mExec.start();
setProcessId();
mWasDownloadStarted = true;
mWasDownloadStopped = false;
}
This is how the command is prepared:
private String buildCommand() {
List <String> command = new ArrayList<>();
command.add("\"" + mManager.mWTLocation + "\"");
command.add("download");
command.add("\"" + mManager.mMagnetUrl + "\"");
if (mManager.mFileIndex >= 0) {
command.add("--select " + mManager.mFileIndex);
}
if (mManager.mSaveTo != null) {
command.add("--out \"" + mManager.mSaveTo + "\"");
}
mManager.mExec.command(command);
String cmdStr = "";
for (String s : command) {
cmdStr = cmdStr.concat(s + " ");
}
return cmdStr.trim();
}
What might be wrong?

Okay, so I was able to fix this issue.
The / character following the path specified as value of --out was causing the problem. In order to fix this, I added a line in node_modules/webtorrent-cli/bin/cmd.js to print the arguments passed to webtorrent:
console.log(process.argv)
With the /, output of this line was something like the following:
[ 'D:\\downloadmanager\\node\\node.exe',
'D:\\downloadmanager\\node\\node_modules\\webtorrent-cli\\bin\\cmd.js',
'download',
'magnet:?xt=urn:btih:08ada5a7a6183aae1e09d831df6748d566095a10&dn=Sintel',
'--select',
'0',
'--out',
'D:\\nf"' ]
Note the " that is included in the path after D:\\nf. When / is removed from the path, the quote disappears and webtorrent behaves as expected.
I doubt that this is a bug in webtorrent. I think zt-exec (or maybe I) was doing something stupid.
Somewhat unrelated, but I think I should also mention that I had to enclose every value for each option with quotes, even the index, to get rid of other nasty errors (e.g.: Error 87, the parameter is incorrect)

Java Bukkit/Spigot - Block Specified Commands

i'm trying to make a plugin, it must block a specified commands setted by config. i've maked this but it doesn't block any command.
Code:
#EventHandler(priority = EventPriority.HIGHEST)
public void onPreprocess(PlayerCommandPreprocessEvent event)
{
Player player = event.getPlayer();
String command = event.getMessage();
List<String> bCmds = this.plugin.cfg.getStringList("blocked-commands");
for (String bCmd : bCmds)
{
if(command.equalsIgnoreCase(bCmd))
{
event.setCancelled(true);
}
}
}
Config:
blocked-commands:
- /pl
- /op
- /sp
- /gravityblock
PS: I've tried to use:
String command = event.getMessage().subString(1);
Thanks for Help... :)

Registered events? implemented listner?
Also your code will not work with additional arguments in the command.
If it contains spaces, split it with " " and get the first element to just get the command
if (cmd.contains(" ")) cmd = cmd.split(" ")[0];

As stated by Bukkit's wiiki, the priorities are called in the following order:
EventPriority.LOWEST
EventPriority.LOW
EventPriority.NORMAL
EventPriority.HIGH
EventPriority.HIGHEST
EventPriority.MONITOR
Maybe you could try to use the Lowest priority, so the event gets cancelled before the command is handled.
I also believe that the command might have arguments, so it might not be equal to the string provided, you should also try
String command = event.getMessage();
if (command.toLowerCase().startsWith("/command") ) {
//cancel
}

Java runtime exec not handling string array well

I have a tomcat servlet which calls a jar function with parameters. The first parameter sometimes contains space. So I tried to use a String array, but it doesn't work at all.
What am I doing wrong?
requestParm = "java -classpath c:\\j\\test.jar test.connect " + fileName + " new";
requestParmarray =new String[]{"java -classpath c:\\j\\test.jar test.connect ",fileName , " new"};
requestParmarrayNew =new String[]{"java -classpath c:\\j\\test.jar test.connect "+fileName+" new"};
// This line works.but can not handle space well
Process ls_proc = Runtime.getRuntime().exec(requestPar);
// Does not call the function at all
Process ls_proc = Runtime.getRuntime().exec(requestParmarray );
// Does not call the function at all
Process ls_proc = Runtime.getRuntime().exec(requestParmarrayNew );
// Does not call the function at all
Process ls_proc = new ProcessBuilder("java -classpath c:\\j\\test.jar test.connect ",fileName, "new" ).start();

You're creating the array incorrectly: Each individual argument must be in its own entry:
String[] requestParmArray = new String[] {
"java",
"-classpath",
"c:\\j\\test.jar",
"test.connect",
fileName,
"new"
};
Process ls_proc = Runtime.getRuntime().exec(requestParmArray);
Also note that I removed the space you had after test.connect; the spaces you put on the command line are just to separate arguments, but in the above, they're separated by being separate entries in the array.

You should make the array in exec() have each parameter as a separate array entry like:
String[] requestPar = new String[]{"java", "-classpath", "c:\\j\\test.jar", "test.connect ", fileName, "new"};
And use it:
Process ls_proc = Runtime.getRuntime().exec(requestPar);

Passing query from php to java

i em trying to fetch some query from an url and then pass them to a java program for further execution. The problem i am facing is that my php code is calling my java program but is not passing the values.
till now i have worked on these codes,
PHP PROGRAM:
<?php
$phonecode= $_GET['phonecode'];
$keyword= $_GET['keyword'];
$location= $_GET['location'];
exec("C:\Users\Abc\Documents\NetBeansProjects\JavaApplication11\src\javaapplication11\main.java -jar jar/name.jar hello" . $phonecode . ' ' . $keyword . ' ' . $location, $output);
print_r($output);
?>
JAVA PROGRAM:
public class Main
{
public static void main(String args[])
{
try
{
String phonecode = args[];
System.out.println(args[]);
System.out.println(phonecode);// i have only tried to print phonecode for now
}
catch(Exception e)
{
System.out.println(e);
}
}
}

Ok, a couple of issues with the Java code you've posted, here's a working version of what you posted:
class Main
{
public static void main(String[] args)//String[] args, not String args[]
{
if (args.length == 0)
{//check to see if we received arguments
System.out.println("No arguments");
return;
}
if ( args.length < 3)
{//and make sure that there are enough args to continue
System.out.println("To few arguments");
return;
}
try
{//this try-catch block can be left out
String phonecode = args[0];//first arg
String keyword = args[1];//second
String location = args[2];//third
//print out the values
System.out.print("Phonecode: ");
System.out.println(phonecode);
System.out.print("keyword: ");
System.out.println(keyword);
System.out.print("location: ");
System.out.println(location);
}
catch(Exception e)
{
System.out.println(e.getMessage());//get the exception MESSAGE
}
}
}
Now, save that as a .java file, and compile it, it should churn out a Main.class file. I compiled it from the command-line:
javac main.java
I don't have netbeans installed, but I suspect the .class file will be written to a different directory, something like:
C:\Users\Abc\Documents\NetBeansProjects\JavaApplication11\bin\javaapplication11\Main.class
// note the BIN
Then, to execute, you need to run the java command, and pass it the path to this Main.class file, leaving out the .class extension. Thus, we end up with:
java /path/to/Main 123 keywrd loc
Should result in the output:
Phonecode: 123
keyword: keywrd
location: loc
In your PHP code:
exec('java /path/to/Main '.escapeshellarg($phonecode). ' '.escapeshellarg($keyword).' '.escapeshellarg($location), $output, $status);
if ($status === 0)
{//always check exit code, 0 indicates success
var_dump($output);
}
else
exit('Error: java exec failed: '.$status);
There are a couple of other issues, too: like $phonecode = $_GET['phonecode']; doesn't check if that $_GET param exists. If it doesn't your code will emit notices. To fix:
$phonecode = isset($_GET['phonecode']) ? $_GET['phonecode'] : '';
Other niggles include: the backslash is a special char in strings, it is used in escape sequences: \n is a newline char. PHP can deal with the *NIX directory separator /, even on windows. Use that, or escape the backslashes (C:\\Users\\Abc\\ and so on).
A file that only contains PHP code doesn't require the closing ?> tag. In fact: it is recommended you leave it out.

your java code should look like
public static void main (String[] args) {
for (String s: args) {
System.out.println(s);
}
}
Note String[] args, not String args[]
Also on PHP side in exec you need space between string hello, and variable $phonecode if you want those to be looked as a 2 separate arguments.

how to use property=value in CLI commons Library

I am trying to use the OptionBuilder.withArgName( "property=value" )
If my Option is called status and my command line was:
--status p=11 s=22
It only succeeds to identify the first argument which is 11 and it fails to identify the second argument...
Option status = OptionBuilder.withLongOpt("status")
.withArgName( "property=value" )
.hasArgs(2)
.withValueSeparator()
.withDescription("Get the status")
.create('s');
options.addOption(status);
Thanks for help in advance

You can access to passed properties using simple modification of passed command line options
--status p=11 --status s=22
or with your short syntax
-s p=11 -s s=22
In this case you can access to your properties simply with code
if (cmd.hasOption("status")) {
Properties props = cmd.getOptionProperties("status");
System.out.println(props.getProperty("p"));
System.out.println(props.getProperty("t"));
}
If you need to use your syntax strictly, you can manually parse your property=value pairs.
In this case you should remove .withValueSeparator() call, and then use
String [] propvalues = cmd.getOptionValues("status");
for (String propvalue : propvalues) {
String [] values = propvalue.split("=");
System.out.println(values[0] + " : " + values[1]);
}