O serviço de observação no Windows 7 não funciona
Esse código funciona bem no Linux, mas não no Windows 7: para obter a atualização do conteúdo do arquivo, preciso clicar no arquivo de saída. Onde está o truque?
Estou usando o Windows 7 prof, NetBeans IDE 8.0 RC1 (versão 201402242200) atualizado para a versão NetBeans 8.0 Patch 1.1, JDK 1.8
package watchfilethreadmod;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.RandomAccessFile;
import java.nio.file.Files;
import static java.nio.file.LinkOption.NOFOLLOW_LINKS;
import java.nio.file.Path;
import java.nio.file.Paths;
import static java.nio.file.StandardWatchEventKinds.*;
import java.nio.file.WatchEvent;
import java.nio.file.WatchKey;
import java.nio.file.WatchService;
import java.util.ArrayList;
import java.util.List;
import java.util.logging.Level;
import java.util.logging.Logger;
public class WatchFileThreadMod {
static class WatchFile {
String fileName;
long lastFilePos;
RandomAccessFile file;
public WatchFile(String _fileName, RandomAccessFile _file) {
fileName = _fileName;
lastFilePos = 0;
file = _file;
}
}
public static void shutDownListener(Thread thread) {
Thread thr = thread;
if (thr != null) {
thr.interrupt();
}
}
private static class MyWatchQueueReader implements Runnable {
/**
* the watchService that is passed in from above
*/
private WatchService myWatcher;
public ArrayList<WatchFile> threadFileToWatch;
public String dirPath;
public MyWatchQueueReader(String _dirPath, WatchService myWatcher, ArrayList<WatchFile> _threadFileToWatch) {
this.myWatcher = myWatcher;
this.threadFileToWatch = _threadFileToWatch;
this.dirPath = _dirPath;
}
private void openFile(WatchFile obj) {
try {
System.out.println("Open file "+obj.fileName);
obj.file = new RandomAccessFile(dirPath + "/" + obj.fileName, "r");
} catch (FileNotFoundException e) {
obj.file = null;
System.out.println("filename " + obj.fileName + " non trovato");
}
obj.lastFilePos = 0;
}
private void process(WatchEvent evt) {
String thisLine;
ArrayList<WatchFile> auxList = threadFileToWatch;
for (WatchFile obj : auxList) {
if (obj.fileName.equals(evt.context().toString())) {
if (obj.file == null) {
openFile(obj);
}
try {
obj.file.seek(obj.lastFilePos);
} catch (IOException e) {
System.err.println("Seek error: " + e);
}
try {
thisLine = obj.file.readLine();
if ((thisLine == null)&&(evt.kind() == ENTRY_MODIFY)) {
System.out.printf("---> thisLine == null received %s event for file: %s\n",
evt.kind(), evt.context());
obj.file.close();
System.out.println("Close file "+obj.fileName);
openFile(obj);
thisLine = obj.file.readLine();
}
while (thisLine != null) { // while loop begins here
if (thisLine.length() > 0) {
if (thisLine.substring(thisLine.length() - 1).equals("*")) {
obj.lastFilePos = obj.file.getFilePointer();
System.out.println(obj.fileName + ": " + thisLine);
}
}
thisLine = obj.file.readLine();
} // end while
} // end try
catch (IOException e) {
System.err.println("Error: " + e);
}
}
}
}
/**
* In order to implement a file watcher, we loop forever ensuring
* requesting to take the next item from the file watchers queue.
*/
@Override
public void run() {
try {
// get the first event before looping
WatchKey key = myWatcher.take();
while (key != null) {
// we have a polled event, now we traverse it and
// receive all the states from it
for (WatchEvent event : key.pollEvents()) {
WatchEvent.Kind eventType = event.kind();
if (eventType == OVERFLOW) {
continue;
}
process(event);
}
key.reset();
key = myWatcher.take();
}
} catch (InterruptedException e) {
ArrayList<WatchFile> auxList = threadFileToWatch;
for (WatchFile obj : auxList) {
if (obj.file != null) {
try {
obj.file.close();
System.out.println("chiusura file " + obj.fileName);
} catch (IOException ex) {
System.out.println("errore in chiusura file");
Logger.getLogger(WatchFileThreadMod.class.getName()).log(Level.SEVERE, null, ex);
}
}
}
//e.printStackTrace();
}
System.out.println("Stopping thread");
}
}
public static void main(String[] args) throws Exception {
// get the directory we want to watch, using the Paths singleton class
//Path toWatch = Paths.get(DIRECTORY_TO_WATCH);
ArrayList<WatchFile> fileToWatch = new ArrayList<>();
String filename;
RandomAccessFile file;
fileToWatch.add(new WatchFile("EURUSD.rlt", new RandomAccessFile(args[0] + "/EURUSD.rlt", "r")));
filename = "EURCHF2.rlt";
try {
file = new RandomAccessFile(args[0] + "/" + filename, "r");
} catch (FileNotFoundException e) {
file = null;
System.out.println("filename " + filename + " non trovato");
}
fileToWatch.add(new WatchFile(filename, file));
fileToWatch = fileToWatch;
Path toWatch = Paths.get(args[0]);
if (toWatch == null) {
throw new UnsupportedOperationException("Directory not found");
}
// Sanity check - Check if path is a folder
try {
Boolean isFolder = (Boolean) Files.getAttribute(toWatch,
"basic:isDirectory", NOFOLLOW_LINKS);
if (!isFolder) {
throw new IllegalArgumentException("Path: " + toWatch + " is not a folder");
}
} catch (IOException ioe) {
// Folder does not exists
ioe.printStackTrace();
}
// make a new watch service that we can register interest in
// directories and files with.
WatchService myWatcher = toWatch.getFileSystem().newWatchService();
// start the file watcher thread below
MyWatchQueueReader fileWatcher = new MyWatchQueueReader(args[0], myWatcher, fileToWatch);
Thread processingThread = new Thread(fileWatcher, "FileWatcher");
processingThread.start();
toWatch.register(myWatcher, ENTRY_CREATE, ENTRY_MODIFY);
}
}
Editar: código reduzido conforme solicitado.
Editar 2: caminho de arquivo
Edição 3: Código Metatrader que estou usando para gravar dados
#property strict
int file_handle;
string InpFileName = _Symbol + ".rlt"; // File name
input string InpDirectoryName = "Data"; // Folder name
int OnInit()
{
ResetLastError();
file_handle = FileOpen(InpDirectoryName + "//" + InpFileName, FILE_SHARE_READ|FILE_WRITE|FILE_TXT|FILE_ANSI);
if(file_handle == INV,ALID_HANDLE) {
PrintFormat("Failed to open %s file, Error code = %d", InpFileName, GetLastError());
ExpertRemove();
}
return INIT_SUCCEEDED;
}
void OnTick()
{
// file_handle = FileOpen(InpDirectoryName + "//" + InpFileName, FILE_SHARE_READ|FILE_WRITE|FILE_TXT|FILE_ANSI);
// Datetime), Bid, Volume
// string s = FileRead()
string s = TimeToStr(TimeGMT()) + "|" + Bid + "|" + Volume[0];
FileWriteString(file_handle, s + "|*\r\n");
FileFlush(file_handle);
//FileClose(file_handle);
}
void OnDeinit(const int reason)
{
FileClose(file_handle);
}
Edição 4: Screencast para mostrar melhor meu problema: os dados são atualizados somente quando clico no arquivo de saída