public PersistentEtmState load() {
PersistentEtmState state = null;
File file = new File(path, filename);
if (file.exists()) {
if (file.canRead()) {
ObjectInputStream in = null;
try {
in = new ObjectInputStream(new FileInputStream(file));
state = (PersistentEtmState) in.readObject();
} catch (Exception e) {
// ignored
LOG.warn("Error loading state from file " + file.getAbsolutePath(), e);
} finally {
if (in != null) {
try {
in.close();
} catch (IOException e) {
// ignored
}
}
}
}
}
return state;
}
private void backupFile(File aDest) {
File backup = new File(aDest.getAbsolutePath() + ".saved");
ObjectInputStream in = null;
ObjectOutputStream out = null;
try {
in = new ObjectInputStream(new FileInputStream(aDest));
out = new ObjectOutputStream(new FileOutputStream(backup));
out.writeObject(in.readObject());
} catch (Exception e) {
LOG.warn("Error writing backup file " + aDest.getAbsolutePath(), e);
} finally {
try {
if (in != null) {
in.close();
}
} catch (IOException e) {
// ingored
}
try {
if (out != null) {
out.close();
}
} catch (IOException e) {
// ignored
}
}
}
public void store(PersistentEtmState state) {
if (!path.exists()) {
if (!path.mkdirs()) {
LOG.warn("Unable to create destination path " + path.getAbsolutePath() + ". Aborting.");
return;
}
}
File destination = new File(path, filename);
if (destination.exists()) {
backupFile(destination);
if (!destination.delete()) {
LOG.warn(
"Unable to delete existing destination target "
+ destination.getAbsolutePath()
+ ". Aborting.");
}
}
ObjectOutputStream out = null;
try {
out = new ObjectOutputStream(new FileOutputStream(destination));
out.writeObject(state);
} catch (Exception e) {
// ignored
LOG.warn("Error writing state to file " + destination.getAbsolutePath(), e);
} finally {
if (out != null) {
try {
out.close();
} catch (IOException e) {
// ignored
}
}
}
}