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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)

Having Java call an Applescript file with arguments

I have a Java program that calls an Applescript file to run, and returns information back to Java. However, I need to also pass some arguments to the Applescript file. The relevant portion of the Java file:
public static void scriptRunner(String[] args) {
// Connect to the database.
ConnectionManager.getInstance().setDBType(DBType.MYSQL);
// Prepare the AppleScript file to be executed.
String homeFolder = System.getenv("HOME");
File scriptFile = new File(homeFolder + "/Documents/Output--Test.applescript");
InputStream scriptStream = null;
try {
scriptStream = FileUtils.openInputStream(scriptFile);
} catch (IOException e) {
JOptionPane.showMessageDialog(null, "Could not find the Output AppleScript file. Please notify Chris McGee", "File not found", JOptionPane.ERROR_MESSAGE);
ConnectionManager.getInstance().close();
System.exit(1);
}
BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(scriptStream));
// These two lines prepare the scripting engine, ready to run the script.
ScriptEngineManager mgr = new ScriptEngineManager();
ScriptEngine engine = mgr.getEngineByName("AppleScript");
// Add the parameters to the engine so they will be passed to the script.
engine.put("javaOrderNum", args[0]);
engine.put("javaShipDate", args[1]);
engine.put("javaInitials", args[2]);
engine.put("javaOverruns", args[3]);
// Run the script and evaluate the result.
log.trace("Run the script and evaluate the result.");
Object result = null;
try {
result = engine.eval(bufferedReader); // Run the script and place the result into an abstract object.
} catch (ScriptException e) {
JOptionPane.showMessageDialog(null, "Either an error occurred with the Output script or the user cancelled it.", "Script error / cancel", JOptionPane.INFORMATION_MESSAGE);
ConnectionManager.getInstance().close();
System.exit(1);
}
log.debug(result); // Check that we received the correct information back from the script.
log.debug("");
.
.
.
Sadly, the engine.put lines, as suggested from a forum I read during my searches to get this problem solved, don't seem to work. The AppleScript file:
-- Get variables passed in
set jOrderNum to item 1 of arguments
set jShipDate to item 2 of arguments
set jInitials to item 3 of arguments
set jOverruns to item 4 of arguments
-- Set the correct folder variable
if (folderExists(POSIX path of "/Volumes/Users/Scripts/")) then
set server_prefix to "/Volumes/Users/Scripts/"
else if (folderExists(POSIX path of "/centralserver/Users/Scripts/")) then
set server_prefix to "/centralserver/Users/Scripts/"
else
display alert "Please connect to the central server, then try again.
If you have already done so, please let Chris McGee know."
end if
with timeout of (30 * 60) seconds
tell application "Adobe InDesign CS6"
set myJavaScript to server_prefix & "sky-artdept/Test/Output.jsx"
set myResult to do script myJavaScript with arguments {jOrderNum, jShipDate, jInitials, jOverruns} language javascript
return myResult
end tell
end timeout
on folderExists(posixPath)
return ((do shell script "if test -e " & quoted form of posixPath & "; then
echo 1;
else
echo 0;
fi") as integer) as boolean
end folderExists
I am given an error that the variable arguments is not defined. What can I try next?

I can't help with the javascript running the applescript. But, you applescript code is missing a declaration. You're asking for "item 1 of arguments" but you never define the variable arguments.
When the script is not inside any handler, it is implicit that it is inside a run() handler. And, since you're needing to pass arguments on run, you should try wrapping your script, minus the on folderExists() handler, inside a run handler that includes the arguments declaration.
on run(arguments)
-- Get variables passed in
set jOrderNum to item 1 of arguments
set jShipDate to item 2 of arguments
…
end timeout
end run
on folderExists(posixPath)
…
end folderExists

Java: populating Scanner with default value on Scanner.nextLine();

I am writing a java program that runs a loop and keeps asking the user for input. The program then does a bunch of things with the string, and asks for another string and repeats.
The issue is that many strings are very similar, so i would like to populate the prompt with the input from the last time in the loop. For instance: If the user enters a value as follows:
Enter the SKU Number: APE-6603/A
... Then the next time it asks for an SKU, it will wait till the user presses enter as normal, but be ready with the last value before the user even types anything:
Enter the SKU Number: APE-6603/A
... And the user can make simple changes very fast like replace the /A with /B and press enter! If the string that holds the user input is called "lookFor", is there a way to populate the prompt with this value in Java? It would be VERY useful!
Thanks!

After discussing this idea with a few people, it seems that what i want is not possible. The way of input is too simple to allow something like this.
My only possible solutions involve not running this from my IDE. I can either elect to use my application, or change the application into a GUI based applet. Running from the console will open up the "Press up" option, as suggested by rchirino, and using a GUI would let the value entered sit there for editing later.
If anyone is looking to do what i posted above, the answer is "Java cant do it!". Sorry. :)

You might want to try something like this:
public String promptandgetWithShowDefault(String prompt, String supplied) {
String prmpt = prompt + " (press Enter for \"" + supplied + "\"):";
String tmpch = null;
System.out.print(prmpt);
tmpch = scanner.nextLine().trim();
if (tmpch == null || tmpch.equals("")) {
return supplied;
} else {
return tmpch;
}
}

If the goal is to get a simple binar answer from the user like:
Would you like to do that? ( y / n ) y
then the empty string returned by the user, in the answer from Dmv, will do the trick, except that when the user types "n" or attempts to delete the trailing "y", it won't disappear, so it would then be clearer to write the prompt like:
Would you like to do that? ( [ y ] / n )
But when the goal is to get a long string, like the original question or a file path for instance, that the user can edit to correct a typo or not to overwrite previous file .... then you definitely need something else which doesn't seem to be available in Java.
Well do it in C then!!! with the help of libreadline...
it's probably possible, easier and more portable to do the same trick in Python, but I have no idea how to code in Python.
Here is a simple Java MRE to illustrate it:
import java.io.BufferedReader;
import java.io.File;
import java.io.InputStreamReader;
public class Main
{
public static void main(String[] args)
{
String path = System.getProperty("user.home") + File.separatorChar + "Documents";
File file = null;
do {
path = askForString("Enter the filepath to open:", path );
if ( ( path == null) || ( path.isBlank())) break;
file = new File( path );
} while ( ! file.exists() );
System.out.println("Openning " + path + "....");
// ......
}
public static String askForString( String message, String defaultString)
{
String response = null;
System.out.println( message);
// any extra String in cmd[] will be added in readline history
String[] cmd = { "/path/to/executable/ask4stringWdefault", defaultString};
try
{
ProcessBuilder pb = new ProcessBuilder(cmd);
// Make sure the subprocess can print on console and capture keyboard events
pb.redirectInput(ProcessBuilder.Redirect.INHERIT);
pb.redirectOutput(ProcessBuilder.Redirect.INHERIT);
Process p = pb.start();
BufferedReader stderrBuffer = new BufferedReader(new InputStreamReader(p.getErrorStream()));
int retcode= p.waitFor();
if ( retcode != 0)
{
System.err.println("The process terminated with error code: " + retcode + "\n" + stderrBuffer.readLine());
return null;
}
response = stderrBuffer.readLine();
} catch( Exception e) {
e.printStackTrace();
}
return response;
}
}
To build the executable "ask4stringWdefault" you need first to get the GNU Readline Library utility and compile it, ideally cross-compile for any platform Java supports, to get a static library that you will link while compiling ( or cross-compiling ) the following C script:
#include <stdio.h>
#include <stdlib.h>
#include <readline/readline.h>
#include <readline/history.h>
const char *defstr;
int prefill(const char *txt, int i);
int main(int argc, const char * argv[])
{
if ( argc < 2)
{
fprintf(stderr, "You must provide a default value\n");
return -1;
} else if ( argc > 2) {
// * optional extra values can be passed to populate history * //
if ( argc > 255) argc = 255;
for ( unsigned char i=0; i < argc; i++)
{
add_history(argv[i]);
}
}
defstr = argv[1];
char *cbuffer;
rl_startup_hook = prefill;
if ((cbuffer = readline(NULL)) == NULL) /* if the user sends EOF, readline will return NULL */
return 1;
fprintf( stderr, "%s\n", cbuffer);
free(cbuffer);
return 0;
}
int prefill(const char *t, int i)
{
rl_insert_text(defstr);
return 0;
}
The result is printed on stderr as it is the only stream that Java can keep track of, stdout and stdin being under the control of the executable subprocess itself.
It works fine on a Mac with arm64 architecture, using Eclipse you can't actually edit the default provided, any character typed at the prompt will be append to default string, but just hitting return will send unchanged default value back, which can be enough for basic testing.

I think I understand what you want to do, but it's rather simple. If your program is a console application (command-line), which I'll assume, then you just need to press the UP key to populate the prompt with the last typed characters.
If you're working with GUI elements then you can check the API documentation for the particular class of object you're using and check out it's fields.
Hope this helps!

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]);
}

Java ProgramCall.run hangs

Busy trying to Call RPG function from Java and got this example from JamesA. But now I am having trouble, here is my code:
AS400 system = new AS400("MachineName");
ProgramCall program = new ProgramCall(system);
try
{
// Initialise the name of the program to run.
String programName = "/QSYS.LIB/LIBNAME.LIB/FUNNAME.PGM";
// Set up the 3 parameters.
ProgramParameter[] parameterList = new ProgramParameter[2];
// First parameter is to input a name.
AS400Text OperationsItemId = new AS400Text(20);
parameterList[0] = new ProgramParameter(OperationsItemId.toBytes("TestID"));
AS400Text CaseMarkingValue = new AS400Text(20);
parameterList[1] = new ProgramParameter(CaseMarkingValue.toBytes("TestData"));
// Set the program name and parameter list.
program.setProgram(programName, parameterList);
// Run the program.
if (program.run() != true)
{
// Report failure.
System.out.println("Program failed!");
// Show the messages.
AS400Message[] messagelist = program.getMessageList();
for (int i = 0; i < messagelist.length; ++i)
{
// Show each message.
System.out.println(messagelist[i]);
}
}
// Else no error, get output data.
else
{
AS400Text text = new AS400Text(50);
System.out.println(text.toObject(parameterList[1].getOutputData()));
System.out.println(text.toObject(parameterList[2].getOutputData()));
}
}
catch (Exception e)
{
//System.out.println("Program " + program.getProgram() + " issued an exception!");
e.printStackTrace();
}
// Done with the system.
system.disconnectAllServices();
The application Hangs at this lineif (program.run() != true), and I wait for about 10 minutes and then I terminate the application.
Any idea what I am doing wrong?
Edit
Here is the message on the job log:
Client request - run program QSYS/QWCRTVCA.
Client request - run program LIBNAME/FUNNAME.
File P6CASEL2 in library *LIBL not found or inline data file missing.
Error message CPF4101 appeared during OPEN.
Cannot resolve to object YOBPSSR. Type and Subtype X'0201' Authority
FUNNAME insert a row into table P6CASEPF through a view called P6CASEL2. P6CASEL2 is in a different library lets say LIBNAME2. Is there away to maybe set the JobDescription?

Are you sure FUNNAME.PGM is terminating and not hung with a MSGW? Check QSYSOPR for any messages.
Class ProgramCall:
NOTE: When the program runs within the host server job, the library list will be the initial library list specified in the job description in the user profile.

So I saw that my problem is that my library list is not setup, and for some reason, the user we are using, does not have a Job Description. So to over come this I added the following code before calling the program.run()
CommandCall command = new CommandCall(system);
command.run("ADDLIBLE LIB(LIBNAME)");
command.run("ADDLIBLE LIB(LIBNAME2)");
This simply add this LIBNAME, and LIBNAME2 to the user's library list.

Oh yes, the problem is Library list not set ... take a look at this discussion on Midrange.com, there are different work-around ...
http://archive.midrange.com/java400-l/200909/msg00032.html
...
Depe