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Java/JavaFX ProcessHandle possibly not finding all processes (Linux/Debian)

I've a JavaFX application where I've a list of a bunch of script files. Once the application loads, it reads it and and checks which ones are running.
To do that I use a ProcessHandle, as mentioned in various examples here on StackOverflow and other guides/tutorials on the internet.
The problem is, it never finds any of them. There for I programmatically started one, which I know for a fact that it will be running, via Process process = new ProcessBuilder("/path/to/file/my_script.sh").start(); - and it won't find this one either.
Contents of my_script.sh:
#!/bin/bash
echo "Wait for 5 seconds"
sleep 5
echo "Completed"
Java code:
// List of PIDs which correspond to the processes shown after "INFO COMMAND:"
System.out.println("ALL PROCESSES: " + ProcessHandle.allProcesses().toList());
Optional<ProcessHandle> scriptProcessHandle = ProcessHandle.allProcesses().filter(processHandle -> {
System.out.println("INFO COMMAND: " + processHandle.info().command());
Optional<String> processOptional = processHandle.info().command();
return processOptional.isPresent() && processOptional.get().equals("my_script.sh");
}).findFirst();
System.out.println("Script process handle is present: " + scriptProcessHandle.isPresent());
if (scriptProcessHandle.isPresent()) { // Always false
// Do stuff
}
Thanks to the good old fashioned System.out.println(), I noticed that I get this in my output console every time:
ALL PROCESSES: [1, 2, 28, 85, 128, 6944, 21174, 29029, 29071]
INFO COMMAND: Optional[/usr/bin/bwrap]
INFO COMMAND: Optional[/usr/bin/bash]
INFO COMMAND: Optional[/app/idea-IC/jbr/bin/java]
INFO COMMAND: Optional[/app/idea-IC/bin/fsnotifier]
INFO COMMAND: Optional[/home/username/.jdks/openjdk-17.0.2/bin/java]
INFO COMMAND: Optional[/usr/bin/bash]
INFO COMMAND: Optional[/home/username/.jdks/openjdk-17.0.2/bin/java]
INFO COMMAND: Optional[/home/username/.jdks/openjdk-17.0.2/bin/java]
INFO COMMAND: Optional[/usr/bin/bash]
Script process handle is present: false
The first line in the Javadoc of ProcessHandle.allProcess() reads:
Returns a snapshot of all processes visible to the current process.
So how come I can't see the rest of the operating system's processes?
I'm looking for a non-os-dependent solution, if possible. Why? For better portability and hopefully less maintenance in the future.
Notes:
A popular solution for GNU/Linux seems to be to check the proc entries, but I don't know if that would work for at least the majority of the most popular distributions - if it doesn't, adding support for them in a different way, would create more testing and maintenance workload.
I'm aware of ps, windir, tasklist.exe possible solutions (worst comes to worst).
I found the JavaSysMon library but it seems dead and unfortunately:
CPU speed on Linux only reports correct values for Intel CPUs
Edit 1:
I'm on Pop_OS! and installed IntelliJ via the PopShop as flatpak.
In order to start it as root as suggested by mr mcwolf, I went to /home/username/.local/share/flatpak/app/com.jetbrains.IntelliJ-IDEA-Community/x86_64/stable/active/export/bin and found com.jetbrains.IntelliJ-IDEA-Community file.
When I run sudo ./com.jetbrains.IntelliJ-IDEA-Community or sudo /usr/bin/flatpak run --branch=stable --arch=x86_64 com.jetbrains.IntelliJ-IDEA-Community in my terminal, I get error: app/com.jetbrains.IntelliJ-IDEA-Community/x86_64/stable not installed
So I opened the file and ran its contents:
exec /usr/bin/flatpak run --branch=stable --arch=x86_64 com.jetbrains.IntelliJ-IDEA-Community "$#"
This opens IntelliJ, but not as root, so instead I ran:
exec sudo /usr/bin/flatpak run --branch=stable --arch=x86_64 com.jetbrains.IntelliJ-IDEA-Community "$#"
Which prompts for a password and when I write it in, the terminal crashes.
Edit 1.1:
(╯°□°）╯︵ ┻━┻ "flatpak run" is not intended to be ran with sudo
Edit 2:
As mr mcwolf said, I downloaded the IntelliJ from the official website, extracted it and ran the idea.sh as root.
Now a lot more processes are shown. 1/3 of them show up as INFO COMMAND: Optional.empty.
scriptProcessHandle.isPresent() is still unfortunately returning false. I searched through them and my_script.sh is nowhere to be found. I also tried processOptional.isPresent() && processOptional.get().equals("/absolute/path/to/my_script.sh") but I still get false on isPresent() and it's not in the list of shown processes.
Though the last sentence might be a different problem. I'll do more digging.
Edit 3:
Combining .commandLine() and .contains() (instead of .equals()) solves the problem mentioned in "Edit 2".
Optional<ProcessHandle> scriptProcessHandle = ProcessHandle.allProcesses().filter(processHandle -> {
System.out.println("INFO COMMAND LINE: " + processHandle.info().commandLine());
Optional<String> processOptional = processHandle.info().commandLine();
return processOptional.isPresent() && processOptional.get().contains("/absolute/path/to/my_script.sh");
}).findFirst();
System.out.println("Script process handle is present: " + scriptProcessHandle.isPresent());
if (scriptProcessHandle.isPresent()) { // Returns true
// Do stuff
}
.commandLine() also shows script arguments, so that must be kept in mind.

Gradle Heap Space Problems with big Standard Output

When I build my project with gradle, the test outputs are huge and I would like to keep them. Therefore, I activated showing the output streams:
test {
testLogging.showStandardStreams = true
}
Unfortunately, gradle does not seem to be able to handle big standard outputs. For demonstration, I created a minimal example: https://github.com/DaGeRe/stdout-test It is a project creating big standard output in a test by
#Test
public void test() {
long start = System.currentTimeMillis();
for (int i = 0; i < 200; i++) {
for (int j = 0; j < 10000; j++) {
long current = System.currentTimeMillis() - start;
System.out.println("This is a simple logging output: " + i + " " + j + " " + current);
}
}
}
If I run this in a standard maven project, it finishes in about 2 minutes:
reichelt#reichelt-desktop:~/workspaces/stdout-test$ time mvn test &> mvn.txt
real 1m34,130s
user 0m31,333s
sys 1m12,296s
If I run it in gradle by time ./gradlew test &> gradle.txt, it does not finish at all (in reasonable time) and the output contains many Expiring Daemon because JVM heap space is exhausted. A way to solve this temporarily would be increasing heap memory (like suggested here: JVM space exhausted when building a project through gradle ), but -Xmx4g does not change anything according to my experiments, and this obviously will not scale for bigger outputs. Also, running ./gradlew -i test does not change the behavior.
The project also contains example files for outputs from maven (https://github.com/DaGeRe/stdout-test/blob/master/mvn.txt) and gradle (https://github.com/DaGeRe/stdout-test/blob/master/gradle.txt - aborted process after ~10 minutes) and one of the heap dumps (https://github.com/DaGeRe/stdout-test/blob/master/java_pid10812.hprof.tar) gradle created. There are only minor increases in the current time in the gradle-log (third output number of every line). Therefore, I assume that gradle mainly has problems printing to stdout and not executing the program.
This shows that, while gradle has some problems printing to stdout, it seems to not block the test execution. Is there any switch or parameter I could give gradle, which forces gradle to directly print to stdout instead of doing its memory-intense processing? Unfortunately, I did not find any in the documentation (https://docs.gradle.org/current/dsl/org.gradle.api.tasks.testing.Test.html).
EDIT Just finished a test run on a server:
reichelt#r147:~/workspaces/dissworkspace/stdout-test$ time ./gradlew test &> gradle.txt
real 28m17,959s
user 216m37,351s
sys 0m12,410s
Ends with an exception:
This is a simple logging output: 89 7842 1416
This is a simple logging output: 89 7843 1416
This is a simple logging output: 89 7844 1416
This is a simple logging output: 89 7845 1416
This is a simple logging output: 89 7846 1416
FAILURE: Build failed with an exception.
* What went wrong:
GC overhead limit exceeded

I don't really have a solution for you, but I want to share a few observations that are too long to put into a comment.
First of all, I can reproduce your OutOfMemory problem from your Github repository. I googled it a bit, and while there are other reports on OOM on this out there, none had a solution. I think it is just a limitation in Gradle when enabling showStandardStreams. I tried fiddling around with the console output type and a few other parameters, but none had an effect.
However, with disabling showStandardStreams, I would not get an OOM. Not even after bumping the number of iterations from 200*10000, that you specified, to 1000*10000. It worked fine and the output got saved to both a .bin, .xml and a .html file for later inspection.
What's more, Gradle ran it more than twice as fast as Maven on my machine:
λ time ./gradlew test &> gradle.txt
real 1m23.113s
user 0m0.015s
sys 0m0.031s
λ time mvn test &> mvn.txt
real 3m6.671s
user 0m0.183s
sys 0m0.566s
Not sure why there is such a big difference between the two.
While I completely agree that it would be nice to use showStandardStreams for large outputs, just like Maven defaults to, it appears it is just not possible unless you can afford to raise the maximum heap size accordingly. On the other hand, having the output saved in the report is also rather nice, which is something you don't get from the Surefire plugin in Maven.

Google OR-Tools in Intellij: UnsatisfiedLinkError

I am setting up a java framework that should use the Google OR-Tools. The code below compiles successfully, but throws an exception at runtime:
Exception in thread "main" java.lang.UnsatisfiedLinkError: com.google.ortools.linearsolver.operations_research_linear_solverJNI.MPSolver_CLP_LINEAR_PROGRAMMING_get()I
at com.google.ortools.linearsolver.operations_research_linear_solverJNI.MPSolver_CLP_LINEAR_PROGRAMMING_get(Native Method)
at com.google.ortools.linearsolver.MPSolver$OptimizationProblemType.<clinit>(MPSolver.java:221)
at Main.main(Main.java:15)
I am using Intellij 2018.3 on Windows 10. I spent a lot of time trying to get this run, but unsuccessful. Based on what I found on the internet, the exception might be caused by poor linking and/or missing external libraries on which OR-Tools depends. However, I don't have the background to resolve this issue, and also Intellij does not highlight anything. Any idea what the problem is?
For completion, this is the code I run:
import com.google.ortools.linearsolver.MPObjective;
import com.google.ortools.linearsolver.MPSolver;
import com.google.ortools.linearsolver.MPVariable;
public final class Main {
public static void main(String[] args) {
// Create the linear solver with the GLOP backend.
MPSolver solver =
new MPSolver("SimpleLpProgram", MPSolver.OptimizationProblemType.GLOP_LINEAR_PROGRAMMING);
// Create the variables x and y.
MPVariable x = solver.makeNumVar(0.0, 1.0, "x");
MPVariable y = solver.makeNumVar(0.0, 2.0, "y");
System.out.println("Number of variables = " + solver.numVariables());
// Create a linear constraint, 0 <= x + y <= 2.
MPConstraint ct = solver.makeConstraint(0.0, 2.0, "ct");
ct.setCoefficient(x, 1);
ct.setCoefficient(y, 1);
System.out.println("Number of constraints = " + solver.numConstraints());
// Create the objective function, 3 * x + y.
MPObjective objective = solver.objective();
objective.setCoefficient(x, 3);
objective.setCoefficient(y, 1);
objective.setMaximization();
solver.solve();
System.out.println("Solution:");
System.out.println("Objective value = " + objective.value());
System.out.println("x = " + x.solutionValue());
System.out.println("y = " + y.solutionValue());
}
}

In my case solution was simple - I just needed to add this singe line of code:
Loader.loadNativeLibraries();
where loader comes from com.google.ortools.Loader

Disclaimer: more a long comment than an answer...
note: I supposed you are using the github repository of or-tools if you used the binary package it should be more or less the same...
1) You must load the jni library which will load the OR-Tools C++ libraries and its dependencies...
/** Simple linear programming example.*/
public class Main {
static {
System.loadLibrary("jniortools");
}
public static void main(String[] args) throws Exception {
2) Did you manage to run the java samples ?
make run SOURCE=ortools/linear_solver/samples/SimpleLpProgram.java
ref: https://developers.google.com/optimization/introduction/java#simple_example
3) As Kayaman pointed out, you must pass the folder where the java runtime can find the native libraries (i.e. the JNI wrapper jniortools.dll and its dependencies libortools.dll)
if you look at the console log you'll see the full command line:
java -Xss2048k -Djava.library.path=lib -cp lib\sample.jar;lib\com.google.ortools.jar;lib\protobuf.jar ...\sample
Which comes from, the makefiles/Makefile.java file:
JAVAFLAGS = -Djava.library.path=$(LIB_DIR)
...
ifeq ($(SOURCE_SUFFIX),.java) # Those rules will be used if SOURCE contain a .java file
$(CLASS_DIR)/$(SOURCE_NAME): $(SOURCE) $(JAVA_OR_TOOLS_LIBS) | $(CLASS_DIR)
-$(DELREC) $(CLASS_DIR)$S$(SOURCE_NAME)
-$(MKDIR_P) $(CLASS_DIR)$S$(SOURCE_NAME)
"$(JAVAC_BIN)" -d $(CLASS_DIR)$S$(SOURCE_NAME) \
-cp $(LIB_DIR)$Scom.google.ortools.jar$(CPSEP)$(LIB_DIR)$Sprotobuf.jar \
$(SOURCE_PATH)
...
.PHONY: run # Run a Java program.
run: build
"$(JAVA_BIN)" -Xss2048k $(JAVAFLAGS) \
-cp $(LIB_DIR)$S$(SOURCE_NAME)$J$(CPSEP)$(LIB_DIR)$Scom.google.ortools.jar$(CPSEP)$(LIB_DIR)$Sprotobuf.jar \
$(SOURCE_NAME) $(ARGS)
endif
src: https://github.com/google/or-tools/blob/46173008fdb15dae1dca0e8fa42a21ed6190b6e4/makefiles/Makefile.java.mk#L15
and
https://github.com/google/or-tools/blob/46173008fdb15dae1dca0e8fa42a21ed6190b6e4/makefiles/Makefile.java.mk#L328-L333
note: you can run make detect_java to know the flags i.e. value of LIB_DIR
note: if you did use the precompiled package the Makefile is here:
https://github.com/google/or-tools/blob/stable/tools/Makefile.cc.java.dotnet
Then after you can try to add this option in Intellij...
You must understand that or-tools is a set of C++ native libraries which are wrapped to Java using the SWIG generator.

To make it work using Intellij (over a windows machine) you need to:
Install Microsoft Visual C++ Redistributable for Visual Studio
Download and extract the OR-Tools library for Java
In intellij, add jar dependency to the 2 jars under the lib folder of the extracted files (each of the 2 jars separately, do not add to lib folder itself. This is why).
Add the lib library path to VM options. In Intellij edit your run-configuration and add to vm options: -Djava.library.path=<path to the lib folder that hold the jars>
Load the jni library statically by adding the below code to your class (as mentioned here.)
static {
System.loadLibrary("jniortools");
}

Error “can't create Java VM” trying to use Ruby Java Bridge (RJB) gem

I'm trying to implement the Ruby Java Bridge (RJB) gem to talk to JVM so that I can run the Open-NLP gem. I have Java installed and running on Windows 8. All indications, at least those I know of, are that Java is installed and operational. But, attempts to use RJB fail with the message "can't create Java VM". (I do sometimes get "undefined method `dlopen' for Fiddle:Module" in other cases, which is also indecipherable.)
I initially just installed JDK per defaults. Due to my 64-bit system, this installed 64-bit Java. I wasn't sure whether or not Ruby and RJB would talk to this, so I installed the 32-bit JRE. However, the error is the same.
Is there any further test I can run to ensure that JVM is working outside of Ruby?
Can someone tell me what I might need to do to run Windows/Ruby/RJB/JVM?
Thanks...
I am running Windows 8 with BitNami Rubystack and Ruby 1.9.3p448.
Java seems to be available according to testjava.jsp:
This is the code, including the URL where I found it:
class FiddleTry
# http://devjete.wordpress.com/2011/01/31/installing-rjb-1-3-4-on-windows-7-32bit-wo-vc/
require 'rjb'
out = Rjb::import('java.lang.System').out <== Line 5 is here
out.print('Hello Rjb from ')
p out._classname
end
Here are the error messages:
C:/Users/Richard/RubymineProjects/Utilities/fiddle_try.rb:5:in `import': can't create Java VM (RuntimeError)
from C:/Users/Richard/RubymineProjects/Utilities/fiddle_try.rb:5:in `<class:FiddleTry>'
from C:/Users/Richard/RubymineProjects/Utilities/fiddle_try.rb:1:in `<top (required)>'
from -e:1:in `load'
from -e:1:in `<main>'
I cannot find any additional information as to why it "can't create Java VM". It would really help if additional information was available to me. I would appreciate either that information or a fix for this. Thanks...
EDIT TO ADD INFORMATION REGARDING OPEN-NLP REQUIREMENT FOR RJB...
This is the code I am trying to run, taken from Github/Open-nlp:
class OpenNlpSample
ENV['JAVA_HOME'] = "C:/Program Files/Java/jdk1.7.0_25" if ENV['JAVA_HOME'].nil?
ENV['LD_LIBRARY_PATH'] = "C:/Program Files/Java/jdk1.7.0_25/bin; C:/Program Files (x86)/Java/jre7" if ENV['LD_LIBRARY_PATH'].nil?
# Load the module
require 'open-nlp'
gem_bin = File.join(Gem.loaded_specs['open-nlp'].full_gem_path, 'bin/')
# Set an alternative path to look for the JAR files.
# Default is gem's bin folder.
# OpenNLP.jar_path = '/path_to_jars/'
# OpenNLP.jar_path = File.expand_path('../../ruby/lib/ruby/gems/1.9.1/gems/open-nlp-0.1.4/bin',__FILE__)
OpenNLP.jar_path = gem_bin
# Set an alternative path to look for the model files.
# Default is gem's bin folder.
# OpenNLP.model_path = '/path_to_models/'
OpenNLP.model_path = gem_bin
# Pass some alternative arguments to the Java VM.
# Default is ['-Xms512M', '-Xmx1024M'].
# OpenNLP.jvm_args = ['-option1', '-option2']
OpenNLP.jvm_args = ['-Xms512M', '-Xmx1024M']
# Redirect VM output to log.txt
OpenNLP.log_file = 'log.txt'
# Set default models for a language.
# OpenNLP.use :language
OpenNLP.use :english
=begin
Examples
Simple tokenizer
=end
OpenNLP.load
sent = "The death of the poet was kept from his poems."
tokenizer = OpenNLP::SimpleTokenizer.new
tokens = tokenizer.tokenize(sent).to_a
# => %w[The death of the poet was kept from his poems .]
#Maximum entropy tokenizer, chunker and POS tagger
OpenNLP.load
chunker = OpenNLP::ChunkerME.new
tokenizer = OpenNLP::TokenizerME.new
tagger = OpenNLP::POSTaggerME.new
sent = "The death of the poet was kept from his poems."
tokens = tokenizer.tokenize(sent).to_a
# => %w[The death of the poet was kept from his poems .]
tags = tagger.tag(tokens).to_a
# => %w[DT NN IN DT NN VBD VBN IN PRP$ NNS .]
chunks = chunker.chunk(tokens, tags).to_a
# => %w[B-NP I-NP B-PP B-NP I-NP B-VP I-VP B-PP B-NP I-NP O]
#Abstract Bottom-Up Parser
OpenNLP.load
sent = "The death of the poet was kept from his poems."
parser = OpenNLP::Parser.new
parse = parser.parse(sent)
parse.get_text.should eql sent
parse.get_span.get_start.should eql 0
parse.get_span.get_end.should eql 46
parse.get_child_count.should eql 1
child = parse.get_children[0]
child.text # => "The death of the poet was kept from his poems."
child.get_child_count # => 3
child.get_head_index #=> 5
child.get_type # => "S"
#Maximum Entropy Name Finder*
OpenNLP.load
text = File.read('./spec/sample.txt').gsub!("\n", "")
tokenizer = OpenNLP::TokenizerME.new
segmenter = OpenNLP::SentenceDetectorME.new
ner_models = ['person', 'time', 'money']
ner_finders = ner_models.map do |model|
OpenNLP::NameFinderME.new("en-ner-#{model}.bin")
end
sentences = segmenter.sent_detect(text)
named_entities = []
sentences.each do |sentence|
tokens = tokenizer.tokenize(sentence)
ner_models.each_with_index do |model,i|
finder = ner_finders[i]
name_spans = finder.find(tokens)
name_spans.each do |name_span|
start = name_span.get_start
stop = name_span.get_end-1
slice = tokens[start..stop].to_a
named_entities << [slice, model]
end
end
end
=begin
Loading specific models
Just pass the name of the model file to the constructor. The gem will search for the file in the OpenNLP.model_path folder.
=end
OpenNLP.load
tokenizer = OpenNLP::TokenizerME.new('en-token.bin')
tagger = OpenNLP::POSTaggerME.new('en-pos-perceptron.bin')
name_finder = OpenNLP::NameFinderME.new('en-ner-person.bin')
# etc.
#Loading specific classes
#You may want to load specific classes from the OpenNLP library that are not loaded by default. The gem provides an API to do this:
# Default base class is opennlp.tools.
OpenNLP.load_class('SomeClassName')
# => OpenNLP::SomeClassName
# Here, we specify another base class.
OpenNLP.load_class('SomeOtherClass', 'opennlp.tools.namefind')
# => OpenNLP::SomeOtherClass
end
At this point in the code:
=begin
Examples
Simple tokenizer
=end
OpenNLP.load
The call chain is to dl.rb, fiddle.rb and jar_loader.rb. jarloader.rb starting line 43:
# Load Rjb and create Java VM.
def self.init_rjb
::Rjb::load(nil, self.jvm_args)
set_java_logging if self.log_file
end
At this point, I get the same error creating JVM. So, I reverted to attempting to run RJB. The error chain is as follows:
Fast Debugger (ruby-debug-ide 0.4.17, ruby-debug-base19x 0.11.30.pre12) listens on 127.0.0.1:59488
Uncaught exception: can't create Java VM
D:/BitNami/rubystack-1.9.3-12/ruby/lib/ruby/gems/1.9.1/gems/bind-it-0.2.7/lib/bind-it/jar_loader.rb:45:in `load'
D:/BitNami/rubystack-1.9.3-12/ruby/lib/ruby/gems/1.9.1/gems/bind-it-0.2.7/lib/bind-it/jar_loader.rb:45:in `init_rjb'
D:/BitNami/rubystack-1.9.3-12/ruby/lib/ruby/gems/1.9.1/gems/bind-it-0.2.7/lib/bind-it/jar_loader.rb:38:in `load_jar_rjb'
D:/BitNami/rubystack-1.9.3-12/ruby/lib/ruby/gems/1.9.1/gems/bind-it-0.2.7/lib/bind-it/jar_loader.rb:27:in `load'
D:/BitNami/rubystack-1.9.3-12/ruby/lib/ruby/gems/1.9.1/gems/bind-it-0.2.7/lib/bind-it/binding.rb:63:in `load_jar'
D:/BitNami/rubystack-1.9.3-12/ruby/lib/ruby/gems/1.9.1/gems/bind-it-0.2.7/lib/bind-it/binding.rb:71:in `block in load_default_jars'
D:/BitNami/rubystack-1.9.3-12/ruby/lib/ruby/gems/1.9.1/gems/bind-it-0.2.7/lib/bind-it/binding.rb:68:in `each'
D:/BitNami/rubystack-1.9.3-12/ruby/lib/ruby/gems/1.9.1/gems/bind-it-0.2.7/lib/bind-it/binding.rb:68:in `load_default_jars'
D:/BitNami/rubystack-1.9.3-12/ruby/lib/ruby/gems/1.9.1/gems/bind-it-0.2.7/lib/bind-it/binding.rb:55:in `bind'
D:/BitNami/rubystack-1.9.3-12/ruby/lib/ruby/gems/1.9.1/gems/open-nlp-0.1.4/lib/open-nlp.rb:14:in `load'
C:/Users/Richard/RubymineProjects/Utilities/open_nlp_sample.rb:32:in `<class:OpenNlpSample>'
C:/Users/Richard/RubymineProjects/Utilities/open_nlp_sample.rb:1:in `<top (required)>'

First, I needed to uninstall Java x64 and install JDK x586 for 32-bit support.
Then, set JAVA_HOME as follows:
JAVA_HOME=C:\Program Files (x86)\Java\jdk1.7.0_40
and add JAVA_HOME to my path:
%JAVA_HOME%\bin;C:\Program Files (x86)\Java\jre7\bin;
This resolved the "can't create Java VM' problem.
Setting $DEBUG=false, or commenting out the line, eliminated all other messages. $DEBUG mode displays error messages that may be caught and resolved so they can be ignored.
After the "can't create Java VM" problem was resolved, all other error messages were of this type and therefore were spurious.
JetBrains support for Rubymine solved this problem for me. They are very good, especially Serge, and I recommend their products because of their support.

Getting IOException while getting free Space on the working drive

I am working on a application which first require to check the available free disk space before running any operation. We have set some Default required Space limit like 512MB, So if any working drive does not have more then 512mb space my program will prompt for less memory space available, please make sufficient space to run the program.
I am using following code for it.
long freeSpace = FileSystemUtils.freeSpaceKb() * 1024;
here I am coverting size into byte first to compare with our standard required size.
Due to the above statement i am gettign following exception:
Error-Command line returned OS error code '3' for command [cmd.exe, /C, dir /-c "F:\MyApp\"]Stacktrace java.io.IOException: Command line returned OS error code '3' for command [cmd.exe, /C, dir /-c "F:\MyApp"]
at org.apache.commons.io.FileSystemUtils.performCommand(FileSystemUtils.java:506)
at org.apache.commons.io.FileSystemUtils.freeSpaceWindows(FileSystemUtils.java:303)
at org.apache.commons.io.FileSystemUtils.freeSpaceOS(FileSystemUtils.java:270)
at org.apache.commons.io.FileSystemUtils.freeSpaceKb(FileSystemUtils.java:206)
at org.apache.commons.io.FileSystemUtils.freeSpaceKb(FileSystemUtils.java:240)
at org.apache.commons.io.FileSystemUtils.freeSpaceKb(FileSystemUtils.java:222)...
The OS returned Error Code is '3' thats mean it is not normal termination.
So now how can I resolve this issue ?
I also found alternative method available in java 1.6 - How to find how much disk space is left using Java?
new File("c:\\").getFreeSpace();
---------------------------------
**More Details :**
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OS Architecture : amd64
Temp Dir : c:\temp\
OS Name : Windows 7
OS Version : 6.1 amd64
Jre Version : 1.6.0_45-b06
User Home : C:\Users\Tej.Kiran
User Language : en
User Country: US
File Separator : \
Current Working Directory : F:\MyApp\

You can try executing that command from a prompt. Run cmd.exe and enter the following:
cmd.exe /C dir /-c "F:\MyApp\"
echo %errorlevel%
Error code 3 means the path doesn't exist, but in this case I wonder if it is related to permissions. Any non-zero errorlevel is a problem. If your Java app needs to know the free space on the drive it is installed on, you can do something like this:
// returns something like "file:/C:/MyApp/my/pkg/MyClass.class"
// -OR- "jar:file:/C:/MyApp/myjar.jar!/my/pkg/MyClass.class"
String myPath = my.pkg.MyClass.class.getResource(MyClass.class).toString();
int start = myPath.indexOf("file:/") + 6;
FileSystemUtils.freeSpaceKb(myPath.substring(start, myPath.indexOf("/", start));
Obviously this code wouldn't work in an applet, but that shouldn't be surprising. The substring logic should also be more robust, but this is just a simple example.