How can I Monitor External files in Java -

i have .exe file, takes .txt file input , returns .txt files outputs.

i have 2 folders names inputfiles , exefolder.

inputfiles folder have many number of input files, files passing argument .exe file.

exefolder have .exe file,output files , 1 input file(we file inputfiles folder).

i want build 1 web application, work in following way.

step 1 :

it checks, how many no of files available in sourcedirectory far requirements.generally every time want find .txt files code maintenance passed filetype argument function.

for this,i wrote following code,it's working fine

 public list<file> listoffilenames(string directorypath,string filetype) {     //creating object file class     file fileobject=new file(directorypath);     //fetching filenames under given path     file[] listoffiles=fileobject.listfiles();     //creating array saving filenames, satisfying far our requirements     list<file> filenames = new arraylist<file>();     (int fileindex = 0; fileindex < listoffiles.length; fileindex++)      {         if (listoffiles[fileindex].isfile())         {           //true condition,array index value file           if (listoffiles[fileindex].getname().endswith(filetype))            {               //system.out.println(listoffiles[fileindex].getname());               filenames .add(listoffiles[fileindex]);           }         }       }     return filenames; } 

step 2:

i used for loop based on length of listoffilenames[dir,filetype],for every iteration file overwrite in exefolder folder. wrote following function.it's working fine

  public void filemoving(file sourcefilepath,string destinationpath,string filename)throws ioexception   { file destinationpathobject=new file(destinationpath); if (         (destinationpathobject.isdirectory())&&         (sourcefilepath.isfile())     )     //both source , destination paths available      {         //creating object file class         file statusfilenameobject=new file(destinationpath+"/"+filename);         if (statusfilenameobject.isfile())             //already file exists in destination path             {                 //deleted file                 statusfilenameobject.delete();                 //paste file source destination path filename value of filename argument                 fileutils.copyfile(sourcefilepath, statusfilenameobject);             }             //file not exists in destination path.             {                 //paste file source destination path filename value of filename argument                 fileutils.copyfile(sourcefilepath, statusfilenameobject);             }     } } 

step 3 :

.exe file run.for wrote following function.working fine in function need add code waiting.

   public void exeternalfileprocessing(string directorypath,string exefilepath,string inputfilename) throws ioexception   { //creating absolute file path of executablefile string executablefilename = directorypath+"/"+exefilepath; //assinging inputfilename argument value inputfile variable string inputfile=inputfilename; //creating processbuilderobject 2 arguments processbuilder processbuilderobject=new processbuilder(executablefilename,inputfile); //creating object file absolutedirectory = new file(directorypath); //assinging  processbuilderobject.directory(absolutedirectory); //starting process processbuilderobject.start(); // //processbuilderobject.wait();  } 

step 4:

once .exe process done, next iteration start. means need monitor .exe process,whether done or not.

for integration, wrote following function name integration.

  public void integration(string filetype,string sourcepath,string directorypath,string executablename,string inputfilename)throws ioexception   {     //created object class     externalfileexecutions externalfileexecutionsobject=new externalfileexecutions();     //calling method class object     list<file> finallistnames=externalfileexecutionsobject.listoffilenames(sourcepath,filetype);     (int fileindex = 0; fileindex < finallistnames.size(); fileindex++)      {         //copy , pasting file sourcepath destination path         externalfileexecutionsobject.filemoving(                                                     finallistnames.get(fileindex),                                                     directorypath,                                                     inputfilename                                                 );         //form here,.exe process start         externalfileexecutionsobject.exeternalfileprocessing(directorypath,executablename,inputfilename);     }  } 

i called these, integration function in main() in following way.

public static void main(string[] args) throws ioexception { //created object class externalfileexecutions externalfileexecutionsobject=new externalfileexecutions(); externalfileexecutionsobject.integration(                                             ".txt",                                             "c:/users/infratab bangalore/desktop/copy",                                             "c:/users/infratab bangalore/desktop/rods",                                             "thmapinfratab1-2.exe",                                             "tmapinput.txt"                                         );  } 

if observer, code,every thing done except .exe monitoring,whether completed or not.once first iteration process done allows next iteration.in second iteration again .exe process.it queue.

actually never work on java,but using stackoverflow wrote above functions. want fix .exe monitoring.

i didn't found anything.

can me.

i hope, guys understand facing.

thanks

for running external process (a .exe program in case), forget runtime.exec(). instead use processbuilder; documentation states it's preferred way start sub-process these days.