My program stucks while executing a command. Can we add a delay timeout in order to proceed even if there is no response from command line ?
try {
if (System.getProperty("os.name").toUpperCase().indexOf("WINDOWS") != -1)
{
p = Runtime.getRuntime().exec("cmd.exe /C " + line);
int exitCode = p.waitFor();
}
else
{
p = Runtime.getRuntime().exec( line );
}
Your question is very vague; I can't really tell what you're asking. However, from what I understand, a break() statement may be of use to you. Perhaps using Thread.sleep() followed by a break()?
Related
I have written a function inside PostgreSQL which has the following code:
for (i = 0; i < 4; i++)
{
Datum dat_value = CStringGetDatum(inp->str[0][i]);
values[i] = datumCopy(dat_value,
stats->attrtype->typbyval,
stats->attrtype->typlen);
}
The input strings are {ALGERIA,ARGENTINA,BRAZIL,CANADA}. The code runs for ALGERIA,ARGENTINA but terminates abruptly for BRAZIL. When I investigated I found that inside datumCopy function, the statement after memcpy is not getting printed. I checked if palloc failed with (s == NULL) condition, but that seems to be not the reason. I think memcpy is failing. Any reason why? Thanks!
Datum
datumCopy(Datum value, bool typByVal, int typLen)
{
Datum res;
if (typByVal)
res = value;
else
{
Size realSize;
char *s;
if (DatumGetPointer(value) == NULL)
return PointerGetDatum(NULL);
realSize = datumGetSize(value, typByVal, typLen);
s = (char *) palloc(realSize);
printf ("Value : %s\n",DatumGetPointer(value));
memcpy(s, DatumGetPointer(value), realSize);
printf ("Not printing \n");
res = PointerGetDatum(s);
}
return res;
}
EDITED : Ok this is really wierd. When the input is one of {BRAZIL,PAKISTAN,FRANCE}, the code terminates abruptly. If I have other countries (I haven't tried extensively, but some countries), the code runs correctly.
EDITED 2 : Found the cause and rectified the issue. If we are passing C strings to datumCopy, we have to pass -2 for typLen parameter. I had been passing it incorrectly.
Thanks!
I have found the cause and rectified the issue.
If we are passing C strings to datumCopy, we have to pass -2 for typLen parameter. I had been passing it incorrectly.
So I have had an issue for a while now and thought it was worth the time to ask the more experienced regex guys if there was a way to fix this issue with a quick search and replace.
So i use a tool which generates java code(not written in java or I would manually fix the cause directly), however, it has an issue calling variables before an object is created.
This always occurs only once per object, but not for every object, the object name is unknown, and the error is always the line directly before the constructor is called. This is the format the error is always in:
this.unknownObjectName.mirror = true;
this.unknownObjectName = new Model(unknown, parameter, values);
I know there should be a trick to fix this, as a simple string replace simply will not work since 'unknownObjectName' is unknown.
Would this even be possible with regex, if so, please enlighten me :)
This is how the code SHOULD read:
this.unknownObjectName = new Model(unknown, parameter, values);
this.unknownObjectName.mirror = true;
For complex models, this error may happen hundreds of times, so this will indeed save a lot of time. That and I would rather walk on hot coals then do mindless busy work like fixing all these manually :)
Edit:
I through together a java app that does the job.
public static void main(String args[]){
File file = new File(args[0]);
File file2 = new File(file.getParentFile(), "fixed-" + file.getName());
try {
if(file2.exists()) {
file2 = new File(file.getParentFile(), "fixed-" + System.currentTimeMillis() + "-" + file.getName());
}
BufferedReader br = new BufferedReader(new InputStreamReader(new FileInputStream(file)));
BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(file2)));
String line, savedline = null, lastInitVar = "";
while((line = br.readLine()) != null){
if(line.contains("= new ")){
String varname = line.substring(0, line.indexOf("=")).trim();
lastInitVar = varname;
}else if(line.contains(".mirror")){
String varname = line.substring(0, line.indexOf(".mirror")).trim();
if(!lastInitVar.equals(varname)){
savedline = line;
continue;
}
}else if(savedline != null && savedline.contains(lastInitVar)){
bw.write(savedline + "\n");
savedline = null;
}
bw.write(line + "\n");
}
bw.flush();
bw.close();
br.close();
} catch (Exception e) {
e.printStackTrace();
}
}
Over thinking it
Write a program to read line by line and when you see a object access before a constructor don't write it out, write out the next line and then write out the buffered line, rinse repeat.
Some people, when confronted with a problem, think "I know, I'll use
regular expressions." Now they have two problems. - Jamie Zawinski
Regular Expressions are for matching patterns not state based logic.
first time long time here.
I just started programming in javascript recently, I'm running into a question of design.
I have some working code that:
1. Waits for specific input from the serial port,
2. When input is found it moves to the next function.
3. The next function sends a command(s) over the serial port and then waits for input again.
Now I have 9 functions defined as stepone() steptwo() etc.... There has to be a better way to do this. Each function is the same except with different variables for input and output desired.
However, I do not want the program to skip steps. It needs to wait for the correct serial input before sending the next command.
I've tried using callback functions referencing each other, it just seems...wrong?
Also, it doesn't work. It doesn't wait for the right input before sending commands.
var waitforinput = function(input, regex, callback)
{
if (regex.search != -1)
callback();
};
var sendcommand = function(command,callback)
{
port.writeline(command);
if (callback)
callback();
};
var connect = function()
{
var int = setInterval(function()
{
waitforinput(input, "Please choose:", function()
{
sendcommand("1", function()
{
waitforinput(input, "You choosed", function()
{
sendcommand("saveenv 1");
});
});
});
},50);
};
I ended up using switch() with cases and keeping track of a variable called step:
step = 1;
switch(step)
{
case 1:
if (inputbuffer.search('Please choose') !== -1)
{
if (!waitdisplaystarted)
{
waitdisplaystarted = true;
waitint = setInterval(showwait,1000);
}
window.$("#instructions").hide();
window.$("#status").html("Step 1: Choosing boot option.");
SELF.sendserialcommand("1");
step = 2;
}
break;
case 2:
if (inputbuffer.search('You choosed 1') !== -1)
{
SELF.sendserialcommand('setenv bootargs "board=ALFA console=ttyATH0,115200 rootfstype=squashfs,jffs2 noinitrd"\r');
setTimeout(function(){SELF.sendserialcommand('saveenv\r');}, 50);
window.$("#status").html("Step 2: Transferring new kernel.");
setTimeout(function(){SELF.sendserialcommand('tftp 0x80600000 kernel.bin\r');}, 2000);
step = 3;
}
break;
case 3:
if (inputbuffer.search('Bytes transferred = ' + 878938) !== -1)
{
window.$("#status").html("Step 3: Erasing old kernel.");
SELF.sendserialcommand('erase 0x9f650000 +0x190000\r');
step = 'finished';
}
}
I have an issue implementing CCR with SQL. It seems that when I step through my code the updates and inserts I am trying to execute work great. But when I run through my interface without any breakpoints, it seems to be working and it shows the inserts, updates, but at the end of the run, nothing got updated to the database.
I proceeded to add a pause to my code every time I pull anew thread from my pool and it works... but that defeats the purpose of async coding right? I want my interface to be faster, not slow it down...
Any suggestions... here is part of my code:
I use two helper classes to set my ports and get a response back...
/// <summary>
/// Gets the Reader, requires connection to be managed
/// </summary>
public static PortSet<Int32, Exception> GetReader(SqlCommand sqlCommand)
{
Port<Int32> portResponse = null;
Port<Exception> portException = null;
GetReaderResponse(sqlCommand, ref portResponse, ref portException);
return new PortSet<Int32, Exception>(portResponse, portException);
}
// Wrapper for SqlCommand's GetResponse
public static void GetReaderResponse(SqlCommand sqlCom,
ref Port<Int32> portResponse, ref Port<Exception> portException)
{
EnsurePortsExist(ref portResponse, ref portException);
sqlCom.BeginExecuteNonQuery(ApmResultToCcrResultFactory.Create(
portResponse, portException,
delegate(IAsyncResult ar) { return sqlCom.EndExecuteNonQuery(ar); }), null);
}
then I do something like this to queue up my calls...
DispatcherQueue queue = CreateDispatcher();
String[] commands = new String[2];
Int32 result = 0;
commands[0] = "exec someupdateStoredProcedure";
commands[1] = "exec someInsertStoredProcedure '" + Settings.Default.RunDate.ToString() + "'";
for (Int32 i = 0; i < commands.Length; i++)
{
using (SqlConnection connSP = new SqlConnection(Settings.Default.nbfConn + ";MultipleActiveResultSets=true;Async=true"))
using (SqlCommand cmdSP = new SqlCommand())
{
connSP.Open();
cmdSP.Connection = connSP;
cmdSP.CommandTimeout = 150;
cmdSP.CommandText = "set arithabort on; " + commands[i];
Arbiter.Activate(queue, Arbiter.Choice(ApmToCcrAdapters.GetReader(cmdSP),
delegate(Int32 reader) { result = reader; },
delegate(Exception e) { result = 0; throw new Exception(e.Message); }));
}
}
where ApmToCcrAdapters is the class name where my helper methods are...
The problem is when I pause my code right after the call to Arbiter.Activate and I check my database, everything looks fine... if I get rid of the pause ad run my code through, nothing happens to the database, and no exceptions are thrown either...
The problem here is that you are calling Arbiter.Activate in the scope of your two using blocks. Don't forget that the CCR task you create is queued and the current thread continues... right past the scope of the using blocks. You've created a race condition, because the Choice must execute before connSP and cmdSP are disposed and that's only going to happen when you're interfering with the thread timings, as you have observed when debugging.
If instead you were to deal with disposal manually in the handler delegates for the Choice, this problem would no longer occur, however this makes for brittle code where it's easy to overlook disposal.
I'd recommend implementing the CCR iterator pattern and collecting results with a MulitpleItemReceive so that you can keep your using statements. It makes for cleaner code. Off the top of my head it would look something like this:
private IEnumerator<ITask> QueryIterator(
string command,
PortSet<Int32,Exception> resultPort)
{
using (SqlConnection connSP =
new SqlConnection(Settings.Default.nbfConn
+ ";MultipleActiveResultSets=true;Async=true"))
using (SqlCommand cmdSP = new SqlCommand())
{
Int32 result = 0;
connSP.Open();
cmdSP.Connection = connSP;
cmdSP.CommandTimeout = 150;
cmdSP.CommandText = "set arithabort on; " + commands[i];
yield return Arbiter.Choice(ApmToCcrAdapters.GetReader(cmdSP),
delegate(Int32 reader) { resultPort.Post(reader); },
delegate(Exception e) { resultPort.Post(e); });
}
}
and you could use it something like this:
var resultPort=new PortSet<Int32,Exception>();
foreach(var command in commands)
{
Arbiter.Activate(queue,
Arbiter.FromIteratorHandler(()=>QueryIterator(command,resultPort))
);
}
Arbiter.Activate(queue,
Arbiter.MultipleItemReceive(
resultPort,
commands.Count(),
(results,exceptions)=>{
//everything is done and you've got 2
//collections here, results and exceptions
//to process as you want
}
)
);
I got a similar problem to this guy while processing 4MB log file. Actually I'm processing multiple files simultaneously but since I keep getting this exception, I decide to just test it for a single file:
val temp = Source.fromFile("./datasource/input.txt")
val dummy = new PrintWriter("test.txt")
var itr = 0
println("Default Buffer size: " + Source.DefaultBufSize)
try {
for( chr <- temp) {
dummy.print(chr.toChar)
itr += 1
if(itr == 75703) println("Passed line 85")
if(itr % 256 == 0){ print("..." + itr); temp.reset; System.gc; }
if(itr == 75703) println("Passed line 87")
if(itr % 2048 == 0) println("")
if(itr == 75703) println("Passed line 89")
}
} finally {
println("\nFalied at itr = " + itr)
}
What I always get is that it will fails at itr = 75703, while my output file will always be 64KB (65536 Bytes exact). No matter where I put temp.reset or System.gc, all experiments ends up the same.
It seems like the problem relies on some memory allocation but I cannot find any useful information on this problem. Any idea on how to solve this one?
All your helps are greatly appreciated
EDIT: Actually I want to process it as binary files, so this technique is not a good solution, many had recommend me to use BufferedInputStream instead.
Why are you calling reset on the Source before it has finished iterating thru the file?
val temp = Source.fromFile("./datasource/input.txt")
try {
for (line <- tem p.getLines) {
//whatever
}
finally temp.reset
Should work just fine with no underflows. See also this question