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JDK dns not respect system dns setting in kubernetes

I custom the k8s core dns file to resolve a custom name.which works fine in pods checked by ping xx.
But it not resolved in java appliation(jdk14).
Nameserver is ok.
/ # cat /etc/resolv.conf
nameserver 10.96.0.10
search xxxx-5-production.svc.cluster.local svc.cluster.local cluster.local
/ # ping xx
PING xx (192.168.65.2): 56 data bytes
64 bytes from 192.168.65.2: seq=0 ttl=37 time=0.787 ms
Edit: I use coredns rewrite host name xx to host.docker.internal,this is change to coredns config
rewrite name regex (^|(?:\S*\.)*)xx\.?$ {1}host.docker.internal
I add some debug code to the entry:
static void runCommand(String... commands) {
try {
ProcessBuilder cat = new ProcessBuilder(commands);
Process start = cat.start();
start.waitFor();
String output = new BufferedReader(new InputStreamReader(start.getInputStream())).lines().collect(Collectors.joining());
String err = new BufferedReader(new InputStreamReader(start.getErrorStream())).lines().collect(Collectors.joining());
log.info("\n{}: stout {}", Arrays.toString(commands),output);
log.info("\n{}: sterr{}", Arrays.toString(commands),err);
} catch (IOException | InterruptedException e) {
log.error(e.getClass().getCanonicalName(), e);
}
}
public static void main(String[] args) {
try {
InetAddress xx = Inet4Address.getByName("xx");
log.info("{}: {}", "InetAddress xx", xx.getHostAddress());
} catch (IOException e) {
log.error(e.getClass().getCanonicalName(), e);
}
runCommand("cat", "/etc/resolv.conf");
runCommand("ping", "xx","-c","1");
runCommand("ping", "host.docker.internal","-c","1");
runCommand("nslookup", "xx");
runCommand("ifconfig");
SpringApplication.run(FileServerApp.class, args);
}
Here is output:
01:01:39.950 [main] ERROR com.j.file_server_app.FileServerApp - java.net.UnknownHostException
java.net.UnknownHostException: xx: Name or service not known
at java.base/java.net.Inet4AddressImpl.lookupAllHostAddr(Native Method)
at java.base/java.net.InetAddress$PlatformNameService.lookupAllHostAddr(InetAddress.java:932)
at java.base/java.net.InetAddress.getAddressesFromNameService(InetAddress.java:1505)
at java.base/java.net.InetAddress$NameServiceAddresses.get(InetAddress.java:851)
at java.base/java.net.InetAddress.getAllByName0(InetAddress.java:1495)
at java.base/java.net.InetAddress.getAllByName(InetAddress.java:1354)
at java.base/java.net.InetAddress.getAllByName(InetAddress.java:1288)
at java.base/java.net.InetAddress.getByName(InetAddress.java:1238)
at com.j.file_server_app.FileServerApp.main(FileServerApp.java:43)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:564)
at org.springframework.boot.loader.MainMethodRunner.run(MainMethodRunner.java:48)
at org.springframework.boot.loader.Launcher.launch(Launcher.java:87)
at org.springframework.boot.loader.Launcher.launch(Launcher.java:51)
at org.springframework.boot.loader.JarLauncher.main(JarLauncher.java:52)
01:01:39.983 [main] INFO com.j.file_server_app.FileServerApp -
[cat, /etc/resolv.conf]: stout nameserver 10.96.0.10search default.svc.cluster.local svc.cluster.local cluster.localoptions ndots:5
01:01:39.985 [main] INFO com.j.file_server_app.FileServerApp -
[cat, /etc/resolv.conf]: sterr
01:01:39.991 [main] INFO com.j.file_server_app.FileServerApp -
[ping, xx, -c, 1]: stout
01:01:39.991 [main] INFO com.j.file_server_app.FileServerApp -
[ping, xx, -c, 1]: sterrping: unknown host
01:01:39.998 [main] INFO com.j.file_server_app.FileServerApp -
[ping, host.docker.internal, -c, 1]: stout PING host.docker.internal (192.168.65.2): 56 data bytes64 bytes from 192.168.65.2: icmp_seq=0 ttl=37 time=0.757 ms--- host.docker.internal ping statistics ---1 packets transmitted, 1 packets received, 0% packet lossround-trip min/avg/max/stddev = 0.757/0.757/0.757/0.000 ms
01:01:39.998 [main] INFO com.j.file_server_app.FileServerApp -
[ping, host.docker.internal, -c, 1]: sterr
01:01:40.045 [main] INFO com.j.file_server_app.FileServerApp -
[nslookup, xx]: stout Server: 10.96.0.10Address: 10.96.0.10#53Non-authoritative answer:Name: host.docker.internalAddress: 192.168.65.2** server can't find xx: NXDOMAIN
01:01:40.045 [main] INFO com.j.file_server_app.FileServerApp -
[nslookup, xx]: sterr
01:01:40.048 [main] INFO com.j.file_server_app.FileServerApp -
[ifconfig]: stout eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 inet 10.1.3.14 netmask 255.255.0.0 broadcast 0.0.0.0 ether ce:71:60:9a:75:05 txqueuelen 0 (Ethernet) RX packets 35 bytes 3776 (3.6 KiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 22 bytes 1650 (1.6 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536 inet 127.0.0.1 netmask 255.0.0.0 loop txqueuelen 1000 (Local Loopback) RX packets 1 bytes 29 (29.0 B) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 1 bytes 29 (29.0 B) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
01:01:40.048 [main] INFO com.j.file_server_app.FileServerApp -
[ifconfig]: sterr
Looks like coredns not working,but in the front end pod,ping is ok,this is front end Dockerfile
FROM library/nginx:stable-alpine
RUN mkdir /app
EXPOSE 80
ADD dist /app
COPY nginx.conf /etc/nginx/nginx.conf
Using docker inspect for fontend and backend container,both network setting are:
"NetworkSettings": {
"Bridge": "",
"SandboxID": "",
"HairpinMode": false,
"LinkLocalIPv6Address": "",
"LinkLocalIPv6PrefixLen": 0,
"Ports": {},
"SandboxKey": "",
"SecondaryIPAddresses": null,
"SecondaryIPv6Addresses": null,
"EndpointID": "",
"Gateway": "",
"GlobalIPv6Address": "",
"GlobalIPv6PrefixLen": 0,
"IPAddress": "",
"IPPrefixLen": 0,
"IPv6Gateway": "",
"MacAddress": "",
"Networks": {}
}
Both frontend and backend has service with type: LoadBalancer,now my question is why the name resolve behave different in this two pods?

No output of Perl script called from Java

I am using Ganymed ssh lib in Java to connect to Linux machine and execute some unix scripts, and display their output.
I am running a parent shell script which in turn runs few other sub-scripts and finally a perl script. All work well for the shell scripts, but when it reaches the perl script, I stop getting any output.
If I run the parent script manually on Linux server I see output from perl without issues.
Here's the relevant java code, connecting to the machine and calling the shell script, and returning a BufferedReader from where the output could be read line by line :
try {
conn = new Connection(server);
conn.connect();
boolean isAuthenticated = conn.authenticateWithPublicKey(user, keyfile, keyfilePass);
if (isAuthenticated == false) {
throw new IOException("Authentication failed.");
}
sess = conn.openSession();
if (param == null) {
sess.execCommand(". ./.bash_profile; cd $APP_HOME; ./parent_script.sh");
}
else {...}
InputStream stdout = new StreamGobbler(sess.getStdout());
reader = new BufferedReader(new InputStreamReader(stdout));
} catch (IOException e) {
e.printStackTrace();
}
My parent shell script called looks like this :
./start1 #script1 output OK
./start2 #script2 output OK
./start3 #script3 output OK
/u01/app/perl_script.pl # NO OUTPUT HERE :(
Would anyone have any idea why this happens ?
EDIT : Adding perl script
#!/u01/app/repo/code/sh/perl.sh
use FindBin qw/ $Bin /;
use File::Basename qw/ dirname /;
use lib (dirname($Bin). "/pm" );
use Capture::Tiny qw/:all/;
use Data::Dumper;
use Archive::Zip;
use XML::Simple;
use MXA;
my $mx = new MXA;
chdir $mx->config->{$APP_HOME};
warn Dumper { targets => $mx->config->{RTBS} };
foreach my $target (keys %{ $mx->config->{RTBS}->{Targets} }) {
my $cfg = $mx->config->{RTBS}->{Targets}->{$target};
my #commands = (
[
...
],
[
'unzip',
'-o',
"$cfg->{ConfigName}.zip",
'Internal/AdapterConfig/Driver.xml'
],
[
'zip',
"$cfg->{ConfigName}.zip",
'Internal/AdapterConfig/Driver.xml'
],
[
'rm -rf Internal'
],
[
"rm -f $cfg->{ConfigName}.zip"
],
);
foreach my $cmnd (#commands) {
warn Dumper { command => $cmnd };
my ($stdout, $stderr, $status) = capture {
system(#{ $cmnd });
};
warn Dumper { stdout => $stdout,
stderr => $stderr,
status => $status };
}
=pod
warn "runnnig -scriptant /ANT_FILE:mxrt.RT_${target}argets_std.xml /ANT_TARGET:exportConfig -jopt:-DconfigName=Fixing -jopt:-DfileName=Fixing.zip');
($stdout, $stderr, $status) = capture {
system('./command.app', '-scriptant -parameters');
}
($stdout, $stderr, $status) = capture {
system('unzip Real-time.zip Internal/AdapterConfig/Driver.xml');
};
my $xml = XMLin('Internal/AdapterConfig/MDPDriver.xml');
print Dumper { xml => $xml };
[[ ${AREAS} == "pr" ]] && {
${PREFIX}/substitute_mdp_driver_parts Internal/AdapterConfig/Driver.xml 123 controller#mdp-a-n1,controller#mdp-a-n2
} || {
${PREFIX}/substitute_mdp_driver_parts Internal/AdapterConfig/Driver.xml z8pnOYpulGnWrR47y5UH0e96IU0OLadFdW/Bm controller#md-uat-n1,controller#md-uat-n2
}
zip Real-time.zip Internal/AdapterConfig/Driver.xml
rm -rf Internal
rm -f Real-time.zip
print $mx->Dump( stdout => $stdout,
stderr => $stderr,
status => $status );
=cut
}

The part of your Perl code that produces the output is:
warn Dumper { stdout => $stdout,
stderr => $stderr,
status => $status };
Looking at the documentation for warn() we see:
Emits a warning, usually by printing it to STDERR
But your Java program is reading from STDOUT.
InputStream stdout = new StreamGobbler(sess.getStdout());
You have a couple of options.
Change your Perl code to send the output to STDOUT instead of STDERR. This could be a simple as changing warn() to print().
When calling the Perl program in the shell script, redirect STDERR to STDOUT.
/u01/app/perl_script.pl 2>&1
I guess you could also set up your Java program to read from STDERR as well. But I'm not a Java programmer, so I wouldn't be able to advise you on the best way to do that.

Golang and apache AB

I have a system with HTTP POST requests and it runs with Spring 5 (standalone tomcat). In short it looks like this:
client (Apache AB) ----> micro service (java or golang) --> RabbitMQ --> Core(spring + tomcat).
The thing is, when I use my Java (Spring) service, it is ok. AB shows this output:
ab -n 1000 -k -s 2 -c 10 -s 60 -p test2.sh -A 113:113 -T 'application/json' https://127.0.0.1:8449/SecureChat/chat/v1/rest-message/send
This is ApacheBench, Version 2.3 <$Revision: 1807734 $>
Copyright 1996 Adam Twiss, Zeus Technology Ltd, http://www.zeustech.net/
Licensed to The Apache Software Foundation, http://www.apache.org/
Benchmarking 127.0.0.1 (be patient)
Completed 100 requests
...
Completed 1000 requests
Finished 1000 requests
Server Software:
Server Hostname: 127.0.0.1
Server Port: 8449
SSL/TLS Protocol: TLSv1.2,ECDHE-RSA-AES256-GCM-SHA384,2048,256
Document Path: /rest-message/send
Document Length: 39 bytes
Concurrency Level: 10
Time taken for tests: 434.853 seconds
Complete requests: 1000
Failed requests: 0
Keep-Alive requests: 0
Total transferred: 498000 bytes
Total body sent: 393000
HTML transferred: 39000 bytes
Requests per second: 2.30 [#/sec] (mean)
Time per request: 4348.528 [ms] (mean)
Time per request: 434.853 [ms] (mean, across all concurrent
requests)
Transfer rate: 1.12 [Kbytes/sec] received
0.88 kb/s sent
2.00 kb/s total
Connection Times (ms)
min mean[+/-sd] median max
Connect: 4 14 7.6 17 53
Processing: 1110 4317 437.2 4285 8383
Waiting: 1107 4314 437.2 4282 8377
Total: 1126 4332 436.8 4300 8403
That is through TLS.
But when I try to use my Golang service I get timeout:
Benchmarking 127.0.0.1 (be patient)...apr_pollset_poll: The timeout specified has expired (70007)
Total of 92 requests completed
And this output:
ab -n 100 -k -s 2 -c 10 -s 60 -p test2.sh -T 'application/json' http://127.0.0.1:8089/
This is ApacheBench, Version 2.3 <$Revision: 1807734 $>
Copyright 1996 Adam Twiss, Zeus Technology Ltd, http://www.zeustech.net/
Licensed to The Apache Software Foundation, http://www.apache.org/
Benchmarking 127.0.0.1 (be patient)...^C
Server Software:
Server Hostname: 127.0.0.1
Server Port: 8089
Document Path: /
Document Length: 39 bytes
Concurrency Level: 10
Time taken for tests: 145.734 seconds
Complete requests: 92
Failed requests: 1
(Connect: 0, Receive: 0, Length: 1, Exceptions: 0)
Keep-Alive requests: 91
Total transferred: 16380 bytes
Total body sent: 32200
HTML transferred: 3549 bytes
Requests per second: 0.63 [#/sec] (mean)
Time per request: 15840.663 [ms] (mean)
Time per request: 1584.066 [ms] (mean, across all concurrent requests)
Transfer rate: 0.11 [Kbytes/sec] received
0.22 kb/s sent
0.33 kb/s total
Connection Times (ms)
min mean[+/-sd] median max
Connect: 0 0 0.0 0 0
Processing: 1229 1494 1955.9 1262 20000
Waiting: 1229 1291 143.8 1262 2212
Total: 1229 1494 1955.9 1262 20000
That is through plane tcp.
I guess I have some mistakes in my code. I made it in one file
func initAmqp(rabbitUrl string) {
var err error
conn, err = amqp.Dial(rabbitUrl)
failOnError(err, "Failed to connect to RabbitMQ")
}
func main() {
err := gcfg.ReadFileInto(&cfg, "config.gcfg")
if err != nil {
log.Fatal(err);
}
PrintConfig(cfg)
if cfg.Section_rabbit.RabbitUrl != "" {
initAmqp(cfg.Section_rabbit.RabbitUrl);
}
mux := http.NewServeMux();
mux.Handle("/", NewLimitHandler(1000, newTestHandler()))
server := http.Server {
Addr: cfg.Section_basic.Port,
Handler: mux,
ReadTimeout: 20 * time.Second,
WriteTimeout: 20 * time.Second,
}
defer conn.Close();
log.Println(server.ListenAndServe());
}
func NewLimitHandler(maxConns int, handler http.Handler) http.Handler {
h := &limitHandler{
connc: make(chan struct{}, maxConns),
handler: handler,
}
for i := 0; i < maxConns; i++ {
h.connc <- struct{}{}
}
return h
}
func newTestHandler() http.Handler {
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
handler(w, r);
})
}
func handler(w http.ResponseWriter, r *http.Request) {
if b, err := ioutil.ReadAll(r.Body); err == nil {
fmt.Println("message is ", string(b));
res := publishMessages(string(b))
w.Write([]byte(res))
w.WriteHeader(http.StatusOK)
counter ++;
}else {
w.WriteHeader(http.StatusInternalServerError)
w.Write([]byte("500 - Something bad happened!"))
}
}
func publishMessages(payload string) string {
ch, err := conn.Channel()
failOnError(err, "Failed to open a channel")
q, err = ch.QueueDeclare(
"", // name
false, // durable
false, // delete when unused
true, // exclusive
false, // noWait
nil, // arguments
)
failOnError(err, "Failed to declare a queue")
msgs, err := ch.Consume(
q.Name, // queue
"", // consumer
true, // auto-ack
false, // exclusive
false, // no-local
false, // no-wait
nil, // args
)
failOnError(err, "Failed to register a consumer")
corrId := randomString(32)
log.Println("corrId ", corrId)
err = ch.Publish(
"", // exchange
cfg.Section_rabbit.RabbitQeue, // routing key
false, // mandatory
false, // immediate
amqp.Publishing{
DeliveryMode: amqp.Transient,
ContentType: "application/json",
CorrelationId: corrId,
Body: []byte(payload),
Timestamp: time.Now(),
ReplyTo: q.Name,
})
failOnError(err, "Failed to Publish on RabbitMQ")
defer ch.Close();
result := "";
for d := range msgs {
if corrId == d.CorrelationId {
failOnError(err, "Failed to convert body to integer")
log.Println("result = ", string(d.Body))
return string(d.Body);
}else {
log.Println("waiting for result = ")
}
}
return result;
}
Can someone help?
EDIT
here are my variables
type limitHandler struct {
connc chan struct{}
handler http.Handler
}
var conn *amqp.Connection
var q amqp.Queue
EDIT 2
func (h *limitHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) {
select {
case <-h.connc:
fmt.Println("ServeHTTP");
h.handler.ServeHTTP(w, req)
h.connc <- struct{}{}
default:
http.Error(w, "503 too busy", http.StatusServiceUnavailable)
}
}
EDIT 3
func failOnError(err error, msg string) {
if err != nil {
log.Fatalf("%s: %s", msg, err)
panic(fmt.Sprintf("%s: %s", msg, err))
}
}

Segmentation Violation using Matlab Javabuilder App in Java Program

I created a GUI in QTJambi which runs the Matlab code when a button is pressed. Everything runs fine and output is received from the Matlab code, but when I close the window of the GUI, I get a segmentation violation, shown below:
------------------------------------------------------------------------
Segmentation violation detected at Sun Apr 26 19:21:03 2015
------------------------------------------------------------------------
Configuration:
Crash Decoding : Disabled
Current Visual : 0x23 (class 4, depth 24)
Default Encoding : UTF-8
GNU C Library : 2.19 stable
MATLAB Architecture: glnxa64
MATLAB Root : /usr/local/MATLAB/MATLAB_Compiler_Runtime/v83
MATLAB Version : 8.3.0.532 (R2014a)
Operating System : Linux 3.13.0-49-generic #83-Ubuntu SMP Fri Apr 10 20:11:33 UTC 2015 x86_64
Processor ID : x86 Family 31 Model 4 Stepping 3, AuthenticAMD
Virtual Machine : Java 1.7.0_79-b14 with Oracle Corporation OpenJDK 64-Bit Server VM mixed mode
Window System : The X.Org Foundation (11501000), display :0.0
Fault Count: 1
Abnormal termination:
Segmentation violation
Register State (from fault):
RAX = 00007fa7adc2f410 RBX = 0000000000000000
RCX = 00007fa7a8365ae0 RDX = 0000000000000000
RSP = 00007fa7ae80f300 RBP = 00007fa7a83458d0
RSI = 0000000000000000 RDI = 00620069006c68a0
R8 = 00007fa7a833f500 R9 = 00007fa7a8364330
R10 = 00007fa7ae80f130 R11 = 0000000000000000
R12 = 0000000000000080 R13 = 0000000000000008
R14 = 00007fa79bffbfb8 R15 = 0000000000000001
RIP = 00007fa7adc2f414 EFL = 0000000000010206
CS = 0033 FS = 0000 GS = 0000
Stack Trace (from fault):
[ 0] 0x00007fa7adc2f414 /lib/x86_64-linux-gnu/libpthread.so.0+00042004 pthread_mutex_lock+00000004
[ 1] 0x00007fa799a9e2c7 /usr/lib/x86_64-linux-gnu/libX11.so.6+00279239 XrmDestroyDatabase+00000039
[ 2] 0x00007fa799a867b3 /usr/lib/x86_64-linux-gnu/libX11.so.6+00182195 _XFreeDisplayStructure+00001123
[ 3] 0x00007fa799a744ef /usr/lib/x86_64-linux-gnu/libX11.so.6+00107759 XCloseDisplay+00000223
[ 4] 0x00007fa79b580d6e /usr/lib/x86_64-linux-gnu/libQtGui.so.4.8.6+02309486
[ 5] 0x00007fa79b517d66 /usr/lib/x86_64-linux-gnu/libQtGui.so.4.8.6+01879398 _ZN12QApplicationD1Ev+00001158
[ 6] 0x00007fa7938bdb57 /usr/lib/jni/libcom_trolltech_qt_gui.so+05557079 _ZN25QtJambiShell_QApplicationD0Ev+00000023
[ 7] 0x00007fa7a0eaac58 /usr/lib/x86_64-linux-gnu/libQtCore.so.4.8.6+01662040 _ZN7QObject5eventEP6QEvent+00000648
[ 8] 0x00007fa79b51bed3 /usr/lib/x86_64-linux-gnu/libQtGui.so.4.8.6+01896147 _ZN12QApplication5eventEP6QEvent+00000067
[ 9] 0x00007fa79b516e2c /usr/lib/x86_64-linux-gnu/libQtGui.so.4.8.6+01875500 _ZN19QApplicationPrivate13notify_helperEP7QObjectP6QEvent+00000140
[ 10] 0x00007fa79b51d4a0 /usr/lib/x86_64-linux-gnu/libQtGui.so.4.8.6+01901728 _ZN12QApplication6notifyEP7QObjectP6QEvent+00000624
[ 11] 0x00007fa7a0e924dd /usr/lib/x86_64-linux-gnu/libQtCore.so.4.8.6+01561821 _ZN16QCoreApplication14notifyInternalEP7QObjectP6QEvent+00000109
[ 12] 0x00007fa7a0e95b3d /usr/lib/x86_64-linux-gnu/libQtCore.so.4.8.6+01575741 _ZN23QCoreApplicationPrivate16sendPostedEventsEP7QObjectiP11QThreadData+00000493
[ 13] 0x00007fa7a0e96bb0 /usr/lib/x86_64-linux-gnu/libQtCore.so.4.8.6+01579952 _ZN16QCoreApplication4execEv+00000192
[ 14] 0x00007fa7a418d7f8 <unknown-module>+00000000
[ 15] 0x00007fa7a41811d4 <unknown-module>+00000000
[ 16] 0x00007fa7a417b4e7 <unknown-module>+00000000
[ 17] 0x00007fa7ad1f1099 /usr/lib/jvm/java-7-openjdk-amd64/jre/lib/amd64/server/libjvm.so+06193305
[ 18] 0x00007fa7ad1f0b38 /usr/lib/jvm/java-7-openjdk-amd64/jre/lib/amd64/server/libjvm.so+06191928
[ 19] 0x00007fa7ad1ffc6b /usr/lib/jvm/java-7-openjdk-amd64/jre/lib/amd64/server/libjvm.so+06253675
[ 20] 0x00007fa7ad210ed8 /usr/lib/jvm/java-7-openjdk-amd64/jre/lib/amd64/server/libjvm.so+06323928
[ 21] 0x00007fa7ae40f1f9 /usr/lib/jvm/java-7-openjdk-amd64/jre/bin/../lib/amd64/jli/libjli.so+00012793
[ 22] 0x00007fa7adc2d182 /lib/x86_64-linux-gnu/libpthread.so.0+00033154
[ 23] 0x00007fa7ae14147d /lib/x86_64-linux-gnu/libc.so.6+01025149 clone+00000109
If this problem is reproducible, please submit a Service Request via:
http://www.mathworks.com/support/contact_us/
A technical support engineer might contact you with further information.
Thank you for your help.

http://uk.mathworks.com/matlabcentral/answers/100053-why-does-jboss-7-1-throw-a-segmentation-violation-when-trying-to-call-a-matlab-builder-ja-2-2-4-r20
I added MWApplication.initialize(MWMCROption.NOJVM); to the main function of my program, before the QTJambi initialisation procedure.

Name of applications running on port in Perl or Java

Xampp comes with a neat executable called xampp-portcheck.exe. This responds with if the ports required are free, and if not, which applications are running on those ports.
I can check if something is running on a port, by accessing the netstat details, but how do I find out the application running on the port within Windows?

The CPAN module Win32::IPHelper provides access to GetExtendedTcpTable which provides the ProcessID for each connection.
Win32::Process::Info gives information about all running processes.
Combining the two, we get:
#!/usr/bin/perl
use strict;
use warnings;
use Win32;
use Win32::API;
use Win32::IPHelper;
use Win32::Process::Info qw( NT );
use Data::Dumper;
my #tcptable;
Win32::IPHelper::GetExtendedTcpTable(\#tcptable, 1);
my $pi = Win32::Process::Info->new;
my %pinfo = map {$_->{ProcessId} => $_ } $pi->GetProcInfo;
for my $conn ( #tcptable ) {
my $pid = $conn->{ProcessId};
$conn->{ProcessName} = $pinfo{$pid}->{Name};
$conn->{ProcessExecutablePath} = $pinfo{$pid}->{ExecutablePath};
}
#tcptable =
sort { $a->[0] cmp $b->[0] }
map {[ sprintf("%s:%s", $_->{LocalAddr}, $_->{LocalPort}) => $_ ]}
#tcptable;
print Dumper \#tcptable;
Output:
[
'0.0.0.0:135',
{
'RemotePort' => 0,
'LocalPort' => 135,
'LocalAddr' => '0.0.0.0',
'State' => 'LISTENING',
'ProcessId' => 1836,
'ProcessName' => 'svchost.exe',
'ProcessExecutablePath' => 'C:\\WINDOWS\\system32\\svchost.exe',
'RemoteAddr' => '0.0.0.0'
}
],
...
[
'192.168.169.150:1841',
{
'RemotePort' => 80,
'LocalPort' => 1841,
'LocalAddr' => '192.168.169.150',
'State' => 'ESTABLISHED',
'ProcessId' => 1868,
'ProcessName' => 'firefox.exe',
'ProcessExecutablePath' => 'C:\\Program Files\\Mozilla Firefox\\firefox.exe',
'RemoteAddr' => '69.59.196.211'
}
],
Phewwww it was exhausting connecting all these dots.