Develop Reference

How to parse file patterns using Apache commons CLI

I'm trying to parse my command line arguments using the apache commons CLI. It might be a bit heavy handed for the example here, but it makes sense in the context of the program I'm creating. I'm trying to read a file pattern filter, similar to what grep uses to select files to process.
My Argument looks like this:
Program --input *.*
I've written a test program to see what the parser is seeing;
public static void main(String[] args) {
Options options = new Options();
options.addOption(new Option(INPUT_FILTER_SHORT, INPUT_FILTER_LONG, true, INPUT_FILTER_DESCRIPTION));
CommandLineParser parser = new BasicParser();
CommandLine cmd = parser.parse(options, args);
System.out.println(cmd.getOptionValue(INPUT_FILTER_SHORT));
}
This prints out:
.classpath
If I change my arguments to:
Program --input test.txt
I get the output:
test.txt
I'm assuming that I have to do something to tell apache commons what * is not a special character? I can't seem to find anything about this online.
I'm experiencing this on Windows (7). I'm fairly certain it's the *.* which is causing the issue as when I swap to using patterns that don't use *, the expected pattern shows up.

Your problem isn't really to do with Commons CLI, but to do with how the shell and the Java executable together process the parameters.
To eliminate other factors, and see what's going on, use a short Java program:
public class ArgsDemo {
public static void main(String[] args) {
for(int i=0; i<args.length; i++) {
System.out.println("" + i + ": " + args[i]);
}
}
}
Play with java ArgsDemo hello world, java ArgsDemo * etc. and observe what happens.
On UNIX and Linux:
Java does no special processing of *. However, the shell does. So if you did:
$ mkdir x
$ cd x
$ touch a b
$ java -jar myjar.jar MyClass *
... then MyClass.main() would be invoked with the parameter array ["a","b"] -- because the UNIX shell expands * to files in the current directory.
You can suppress this by escaping:
$ java -jar myjar MyClass * // main() sees ["*"])
(Note that a UNIX shell wouldn't expand *.* to .classpath because this form would ignore "hidden" files starting with .)
On Windows
cmd.exe does not do UNIX-style wildcard expansion. If you supply * as a parameter to a command in Windows, the command gets a literal *. So for example, PKUNZIP *.zip passes *.zip to PKUNZIP.EXE, and it's up to that program to expand the wildcard if it wants to.
Since some release of Java 7, the Java executable for Windows does some wildcard to filename expansion of its own, before passing the parameters to your main() class.
I've not been able to find clear documentation of Java-for-Windows' wildcard expansion rules, but you should be able to control it with quoting, escaping the quotes to prevent cmd.exe interpreting them:
> java.exe -jar myjar.jar MyClass """*.*"""
(Untested as I don't have a Windows box handy, and quoting in cmd.exe is a bit of a beast - do please experiment and either edit the above or leave a comment)

how to use windows default voice using java? [duplicate]

Is there a way to use the MS Speech utility from command line? I can do it on a mac, but can't find any reference to it on Windows XP.

My 2 cents on the topic, command line one-liners:
on Win using PowerShell.exe
PowerShell -Command "Add-Type –AssemblyName System.Speech; (New-Object System.Speech.Synthesis.SpeechSynthesizer).Speak('hello');"
on Win using mshta.exe
mshta vbscript:Execute("CreateObject(""SAPI.SpVoice"").Speak(""Hello"")(window.close)")
on OSX using say
say "hello"
Ubuntu Desktop (>=2015) using native spd-say
spd-say "hello"
on any other Linux
refer to How to text-to-speech output using command-line?
commandline function using google TTS (wget to mp3->mplayer)
command using google with mplayer directly:
/usr/bin/mplayer -ao alsa -really-quiet -noconsolecontrols "http://translate.google.com/translate_tts?ie=UTF-8&client=tw-ob&q=Hello%20World&tl=en";
on Raspberry Pi, Win, OSX (or any remote) using Node-Red
npm i node-red-contrib-sysmessage

There's a nice open source program that does what you're asking for on Windows called Peter's Text to Speech available here: http://jampal.sourceforge.net/ptts.html
It contains a binary called ptts.exe that will speak text from standard input, so you can run it like this:
echo hello there | ptts.exe
Alternatively, you could use the following three line VBS script to get similar basic TTS:
'say.vbs
set s = CreateObject("SAPI.SpVoice")
s.Speak Wscript.Arguments(0), 3
s.WaitUntilDone(1000)
And you could invoke that from the command line like this:
cscript say.vbs "hello there"
If you go the script route, you'll probably want to find some more extensive code examples with a variable timeout and error handling.
Hope it helps.

There's also Balabolka: http://www.cross-plus-a.com/bconsole.htm
It has a command line tool balcon.exe. You can use it like this:
List voices:
balcon.exe -l
Speak file:
balcon.exe -n "IVONA 2 Jennifer" -f file.txt
Speak from the command-line:
balcon.exe -n "IVONA 2 Jennifer" -t "hello there"
More command line options are available. I tried it on Ubuntu with SAPI5 installed in Wine. It works just fine.

If you can't find a command you can always wrap the System.Speech.Synthesis.SpeechSynthesizer from .Net 3.0 (Don't forget to reference "System.Speech")
using System.Speech.Synthesis;
namespace Talk
{
class Program
{
static void Main(string[] args)
{
using (var ss = new SpeechSynthesizer())
foreach (var toSay in args)
ss.Speak(toSay);
}
}
}

There is a powershell way also:
Create a file called speak.ps1
param([string]$inputText)
Add-Type –AssemblyName System.Speech
$synth = New-Object System.Speech.Synthesis.SpeechSynthesizer
$synth.Speak($inputText);
Then you can call it
.\speak.ps1 "I'm sorry Dave, I'm afraid I can't do that"

rem The user decides what to convert here
:input
cls
echo Type in what you want the computer to say and then press the enter key.
echo.
set /p text=
rem Making the temp file
:num
set num=%random%
if exist temp%num%.vbs goto num
echo ' > "temp%num%.vbs"
echo set speech = Wscript.CreateObject("SAPI.spVoice") >> "temp%num%.vbs"
echo speech.speak "%text%" >> "temp%num%.vbs"
start temp%num%.vbs
pause
del temp%num%.vbs
goto input
pause

Your best approach is to write a small command line utility that will do it for you. It would not be a lot of work - just read text in and then use the ms tts library.
Another alternative is to use Cepstral. It comes with a nice command line utility and sounds light years better than the ms tts.

Running a Python program in Java using Jython

I wrote a Python program that consists out of five .py script files.
I want to execute the main of those python scripts from within a Java Application.
What are my options to do so? Using the PythonInterpreter doesn't work, as for example the datetime module can't be loaded from Jython (and I don't want the user to determine his Python path for those dependencies to work).
I compiled the whole folder to .class files using Jython's compileall. Can I embed these .class files somehow to execute the main file from within my Java Application, or how should I proceed?

Have a look at the ProcessBuilder class in java: https://docs.oracle.com/javase/7/docs/api/java/lang/ProcessBuilder.html.
The command used in the java constructor should be the same as what you would type in a command line. For example:
Process p = new ProcessBuilder("python", "myScript.py", "firstargument").start();
(the process builder does the same thing as the python subprocess module).
Have a look at running scripts through processbuilder
N.B. as for the Jython part of the question, if you go to the jython website (have a look at the FAQ section of their website www.jython.org). Check the entry "use jython from java".

I'm also interested in running Python code directly within Java, using Jython, and avoiding the need for an installed Python interpreter.
The article, 'Embedding Jython in Java Applications' explains how to reference an external *.py Python script, and pass it argument parameters, no installed Python interpreter necessary:
#pymodule.py - make this file accessible to your Java code
def square(value):
return value*value
This function can then be executed either by creating a string that
executes it, or by retrieving a pointer to the function and calling
its call method with the correct parameters:
//Java code implementing Jython and calling pymodule.py
import org.python.util.PythonInterpreter;
import org.python.core.*;
public class ImportExample {
public static void main(String [] args) throws PyException
{
PythonInterpreter pi = new PythonInterpreter();
pi.exec("from pymodule import square");
pi.set("integer", new PyInteger(42));
pi.exec("result = square(integer)");
pi.exec("print(result)");
PyInteger result = (PyInteger)pi.get("result");
System.out.println("result: "+ result.asInt());
PyFunction pf = (PyFunction)pi.get("square");
System.out.println(pf.__call__(new PyInteger(5)));
}
}
Jython's Maven/Gradle/etc dependency strings can be found at http://mvnrepository.com/artifact/org.python/jython-standalone/2.7.1
Jython JavaDoc

It is possible to load the other modules. You just need to specify the python path where your custom modules can be found. See the following test case and I am using the Python datatime/math modules inside my calling function (my_maths()) and I have multiple python files in the python.path which are imported by the main.py
#Test
public void testJython() {
Properties properties = System.getProperties();
properties.put("python.path", ".\\src\\test\\resources");
PythonInterpreter.initialize(System.getProperties(), properties, new String[0]);
PythonInterpreter interpreter = new PythonInterpreter();
interpreter.execfile(".\\src\\test\\resources\\main.py");
interpreter.set("id", 150); //set variable value
interpreter.exec("val = my_maths(id)"); //the calling function in main.py
Integer returnVal = (Integer) interpreter.eval("val").__tojava__(Integer.class);
System.out.println("return from python: " + returnVal);
}

Is it possible to get the command used to launch the jvm in java?

I would like to know if it is possible to get from code the command used to launch a java program.
E.g. if I launch a java program with:
java -cp lib1:lib2:... -jar mylib.jar com.foo.Bar
I would like to get the exact string (jvm parameters included).
Is it possible?
Comment on the bounty and the question
Thank you all for your responses. Unfortunately, I did not get the answer I was initally looking for. I was hoping there was some portable solution to get the complete java command from within the program itself (including classpath etc.). As it seems there are no portable solution and since I am using Linux I am using the responses of agodinhost and Luigi R. Viggiano to solve my problem. However I give the bounty to rahulroc for the most complete (portable) response. For the rest an upvote for all :)

The below mentioned code should show all JVM parameters, arguments passed to the main method as well as the main class name.
import java.lang.management.ManagementFactory;
import java.lang.management.RuntimeMXBean;
import java.util.List;
public static void main(String[] args) {
RuntimeMXBean bean = ManagementFactory.getRuntimeMXBean();
List<String> jvmArgs = bean.getInputArguments();
for (int i = 0; i < jvmArgs.size(); i++) {
System.out.println( jvmArgs.get( i ) );
}
System.out.println(" -classpath " + System.getProperty("java.class.path"));
// print the non-JVM command line arguments
// print name of the main class with its arguments, like org.ClassName param1 param2
System.out.println(" " + System.getProperty("sun.java.command"));
}
javadoc for getInputArguments
Returns the input arguments passed to the Java virtual machine which
does not include the arguments to the main method. This method returns
an empty list if there is no input argument to the Java virtual
machine.
Some Java virtual machine implementations may take input arguments
from multiple different sources: for examples, arguments passed from
the application that launches the Java virtual machine such as the
'java' command, environment variables, configuration files, etc.
Typically, not all command-line options to the 'java' command are
passed to the Java virtual machine. Thus, the returned input arguments
may not include all command-line options.
You can also take a look at : jps
It's a Java program that is able to get the full command line for all
Java processes, including full class name of main class and JVM
options.
You can find a good summary of various JVM tools, including
Java Application Launcher links to :
ManagementFactory.getRuntimeMXBean() - Returns the managed bean for the runtime system of the Java virtual machine.
getInputArguments() javadoc
determine if JVM is running in debug mode

You can use this to retrieve the VM parameters :
public static void main(String args[]) {
List<String> inputArguments = ManagementFactory.getRuntimeMXBean().getInputArguments();
System.out.println("input arguments = " + inputArguments);
}
However it won't give you all the command line (only gives the JVM arguments, no main class nor parameters). Sample output:
input arguments = [-Dfile.encoding=UTF-8, -XX:-UseTLAB, -Xms2000m, -Xmx2000m, -XX:+PrintCompilation, -XX:+PrintGC]

It only works on Sun Oracle JVM: System.getProperty("sun.java.command")
Additionally, you can have a look at JavaSysMon, it can report command line of active processes. To check which is the current JVM Process check here: How can a Java program get its own process ID?

in a linux machine would be easier to run:
ps -ef | grep java
this command will list all java programs running with it's used parameters.
Not sure about what can be used in a windows environment.

In the task manager on Win2003 you can enable the display of a column that displays the command like it does on linux. Or, you can do it from the command line like so:
wmic.exe PROCESS where "name like '%java%'" get Processid,Caption,Commandline

Calling a java program from another

How do i call a Java command from a stand alone java program.
I understand that Runtime.getRuntime().exec("cmd c/ javac <>.java"); would work. However, this would be platform specific.
Any other APIs available that could make it work in j2sdk1.4 ?

If you can run everything in the same JVM, you could do something like this:
public class Launcher {
...
public static void main(String[] args) throws Exception {
launch(Class.forName(args[0]), programArgs(args, 1));
}
protected static void launch(Class program, String[] args) throws Exception {
Method main = program.getMethod("main", new Class[]{String[].class});
main.invoke(null, new Object[]{args});
}
protected static String[] programArgs(String[] sourceArgs, int n) {
String[] destArgs = new String[sourceArgs.length - n];
System.arraycopy(sourceArgs, n, destArgs, 0, destArgs.length);
return destArgs;
}
And run it with a command line like this:
java Launcher OtherClassWithMainMethod %CMD_LINE_ARGS%

Calling Runtime.getRuntime().exec() is not only platform specific, it is extremely inefficient. It will result in spawning a brand new shell and an entire jvm which could potentially be very expensive depending on the dependencies of this application (no pun intended).
The best way to execute "external" Java code would be to place it in your CLASSPATH. If you must call an application's main method you can simply import and call the method directly. This could be done like so:
import my.externals.SomeMain
// call as if we are running from console
SomeMain.main(new String[] {"some", "console", "arguments"})
Of course, the best case scenario would be to simply use this as an external library and access the code you need without having to call SomeMain.main(). Adhering to best practices and writing proper encapsulated modular objects allows for much greater portability and ease of use when being used by other applications.

When you leave the JVM and move to system commands, then you have to deal with the platform specific commands yourself. The JVM offers a good way for abstraction, so why move away?
If you want to execute java specific binaries, check out the ant libraries of java. You can execute ant scripts from java which execute platform depending commands.

Java programming from quercus php on GAE:
import com.newatlanta.commons.vfs.provider.gae.GaeVFS;
import org.apache.commons.io.IOUtils;
import java.lang.Long;
import java.lang.Boolean;
GaeVFS::setRootPath(quercus_servlet_request()->getSession(true)->getServletContext()->getRealPath('/'));
define('VFSM', GaeVFS::getManager());
//VFSM->resolveFile('gae://gaevfs')->createFolder();
$file=VFSM->resolveFile('gae://gaevfs/tmp1');
//$file->createFile();
$text='pp';
$method=$file->getClass()->getDeclaredMethod('updateContentSize', array(Long::TYPE, Boolean::TYPE));
$method->setAccessible(true);
$method->invoke($file, strlen($text), true);
$out=$file->getContent()->getOutputStream();
IOUtils::write($text, $out, 'UTF8');
$out->close();
$in=$file->getContent()->getInputStream();
$method=$file->getClass()->getDeclaredMethod('doGetContentSize',array());
$method->setAccessible(true);
$len=$method->invoke($file);
$whole=IOUtils::toString($in, 'UTF8').':'.$len."<br>";
$in->close();
echo $whole;
GaeVFS::clearFilesCache();
GaeVFS::close();