Develop Reference

Running batch file in java

I am trying to run a batch file using java. The batch file in turn runs a python program. So i should wait till the batch file is done and then proceed with my program.
Problems facing:
I could not run batch file in background. I am able to run it only via start
Process p = Runtime.getRuntime().exec("cmd /c start c://GCTI//IA/QAART//testercheck.bat");
once the batch file ran, it is not closing automatically.
Batch file
"C:\Python27\python.exe" -i "C:\GCTI\IA\QAART\tester\test_monitor.py" -init "C:\GCTI\IA\EpiPhone\Dispatcher6\init\INIT_Designer_QAART_Dispatcher_Chat.PY" -testlist "C:\GCTI\IA\ASR_QAART\dat files\ChatAutomation\chat.dat" 23
Can you please help me to run this batch ile in background?

You don't need the batch file. You can execute the Python program directly from Java code using class java.lang.ProcessBuilder.
ProcessBuilder pb = new ProcessBuilder("C:\\Python27\\python.exe",
"-i",
"C:\\GCTI\\IA\QAART\\tester\\test_monitor.py",
"-init",
"C:\\GCTI\\IA\\EpiPhone\\Dispatcher6\\init\\INIT_Designer_QAART_Dispatcher_Chat.PY",
"-testlist",
"C:\\GCTI\\IA\\ASR_QAART\\dat files\\ChatAutomation\\chat.dat",
"23");
Process p = pb.start();
int result = p.waitFor();
Refer to other methods in class ProcessBuilder for handling the output of the Python script, for example method inheritIO

Java Spring Boot failing to find Python Script in resources folder

I am trying to call python Scripts(in resources) from my Java class.
This is my code spinnet
String res = "/Scripts/Brokers/__init__.py";
URL pathUrl = this.getClass().getResource(res);
String path = "";
if(pathUrl != null)
path = pathUrl.toString();
ProcessBuilder pb = new ProcessBuilder("/usr/bin/python3.6", path);
ProcessBuilder is giving error No such file or directory.
P.S.
value of path = "file:/home/path-to-project/project-name/out/production/resources/Scripts/Brokers/\__init__.py"
Also how to include python scripts in jar file to run the project on linux server.
I am stuck with this issue since last 3 days. Please suggest.

From java doc:
https://docs.oracle.com/javase/7/docs/api/java/lang/ProcessBuilder.html
Starting a new process which uses the default working directory and
environment is easy:
Process p = new ProcessBuilder("myCommand", "myArg").start();
So basically, you going to fork a sub process that will
start a python interpreter
with the python script that you have provided as argument.
The path to your script should be a normal path that your OS can understand, therefore you should not give a URI? like path (protocol:address/path).
if (path.contains(":"))
path = (path.split(":"))[1];
Also the backslash \ before __init__.py looks suspicious.
You should be able to run ls /home/path-to-project/project-name/out/production/resources/Scripts/Brokers/__init__.py and see the file, the same goes for ls /usr/bin/python3.6.

Error: Could not find or load main class in python

I am trying to run this command in Python:
java JSHOP2.InternalDomain logistics
It works well when I run it in cmd.
I wrote this in Python:
args = ['java',
r"-classpath",
r".;./JSHOP2.jar;./antlr.jar",
r"JSHOP2.InternalDomain",
thisDir+"/logistics"
]
proc = subprocess.Popen(args, stdout=subprocess.PIPE)
proc.communicate()
I have the jar files in the current directory.
but I got this error:
Error: Could not find or load main class JSHOP2.InternalDomain
Does anyone know what the problem is? can't it find the jar files?

You can't count on the current working directory always being the same when running your Python code. Explicitly set a working directory using the cwd argument:
proc = subprocess.Popen(args, stdout=subprocess.PIPE,
cwd='/directory/containing/jarfiles')
Alternatively, use absolute paths in your -classpath commandline argument. If that path is thisDir, then use that:
proc = subprocess.Popen(args, stdout=subprocess.PIPE,
cwd=thisDir)

Open a file on Openshift using Java

I have a DIY cartridge. My project structure looks like
MY_PROJECT
-diy
-myProgram.jar
-resources
-file1, file2...
-.openshift
-action_hooks
-start
The myProgram.jar uses files from the folder 'resources'.
The code looks like
File imageFolder = new File("resources");
System.out.println("Image Folder read:"+imageFolder.canRead()); //canRead returns false
File[] listOfFiles = imageFolder.listFiles(); // here I get null
The program runs by action hook 'start':
nohup java -jar $OPENSHIFT_REPO_DIR/diy/*.jar --server.port=${OPENSHIFT_DIY_PORT} --server.address=${OPENSHIFT_DIY_IP} &
The problem is that I'm not able to work with files.
As described in code comments I get null on listFiles().
If I run the program on Openshift manually(ssh to server/$OPENSHIFT_REPO_DIR/diy/ and run java -jar ...) it works, but it doesn't work via action_hooks.
Thank you in advance!

I resolved the issue with Openshift env variable 'OPENSHIFT_REPO_DIR'.
Instead of using relative path
new File("resources");
I use absolute
String absolutePath = System.getenv("OPENSHIFT_REPO_DIR");
new File(absolutePath + "diy/resources")

Executing python compiled script (.pyc) in Java

I have a python compiled script (script.pyc , I haven't the .py file)that work well from my windows command prompt, and I want to execute it from my Java's application.
I tried to use runtime() method :
Runtime runtime = Runtime.getRuntime();
runtime.exec(new String[] {"C:\\toto\\tools\\script.pyc" ,"arg","arg2" });
but I get an error :
Exception in thread "main" java.io.IOException: Cannot run program "C:\Nuance\VoCon Hybrid\SDK_v4_3\tools\clctodict.pyc": CreateProcess error=193, %1 n?est pas une application Win32 valid
The script work well in my terminal ("arg" is a txt file, "arg2" is the output name, and the script does its job without any problem).
I also try to launch my script with getDesktop() :
File fie = new File("C:\\toto\\tools\\script.pyc" ,"arg","arg2");
Desktop.getDesktop().open(fie);
There is no problem, but I can't add argument, so I can just see a terminal windows opening during a few second before disappearing instantly.
I have also tried to use JPython, without success too (maybe we can't use methode "execfile" on a .pyc????)

You can do something like
Process p = Runtime.getRuntime().exec(new String[]{"python.exe" ... other args)
Then you can invoke p.waitFor() to wait for the end of the process and p.exitValue() to test if the program exited successfully.
You can also get the output stream via p.getOutputStream() to retrieve the text printed by your python script
Please refer to the class documentation for further information : http://docs.oracle.com/javase/6/docs/api/java/lang/Process.html

Just like you need a jvm to run a .class, you need a python interpreter to run a .pyc.
Try something like:
runtime.exec(new String[] {"c:\\Python26\\bin\\python.exe", "C:\\toto\\tools\\script.pyc" ,"arg","arg2" });