For the purpose of reading in text documents, I realize that I need to find the java file in the bin instead of the src, using Eclipse. How would I short-code that in my programs? Instead of using "C://Users/Brian/workspace/Test/bin/file", what could I do to bypass this?
}catch(FileNotFoundException e){
}
This is for what programmers should be punished for.
Do not ever make things like this - if there would be an error, you'll never notice this.
}catch(FileNotFoundException e){
System.out.println(e);
}
If your file doesn't exists, you can't read/scan it..
Related
Main context
We're actually trying to get a multi-threading version of Ghostscript x64 DLL, to make use of it through Ghostscript .NET. This component is supposed to "allow runing multiple Ghostscript instances simultaneously within a single process", but, as we have checked in our project, works fine until concurrent requests are made to the application. Same behavior can be replicated lauching same method using Tasks. The error description that raises in both cases, just when a call to the process is made until the last is being executed, is:
An error occured when call to 'gsapi_new_instance' is made: -100
Even it does no seem to be related with .NET directly, I will post a sample of our C# method code, just for contextualize.
// Define switches...
string[] switchesArray = switches.ToArray();
using (GhostscriptProcessor procesador = new GhostscriptProcessor())
{
try
{
procesador.StartProcessing(switchesArray, null);
byte[] destinationFile = System.IO.File.ReadAllBytes(destinationPath);
return destinationFile;
}
catch (Exception ex)
{
throw ex;
}
finally
{
System.IO.File.Delete(sourceFile);
}
}
THREADSAFE solution
Starting our investigation, we found this KenS's answer on this post, indicating that Ghostscript DLL must be generated with GS_THREADSAFE compiler definition.
To clarify, as we make use of Ghostscript 9.52 x64 to generate our PDFs, we need this x64 DLL compiled for Release configuration. After trying to compile Ghostscript sources on Windows 10 x64 machine, using Visual Studio Community 2017 and Visual Studio Community 2019, we finally managed to build and generate all items (only with VS Community 2019) without GS_THREADSAFE parameter, just to confirm that compilation is fine, and we check that the DLLs and executables are working. For this process we took in mind all we found in Ghostscript official documentation.
As we have no other guide to include this GS_THREADSAFE parameter, we followed the instructions given in this solution, including XCFLAGS="-DGS_THREADSAFE=1" on nmake build commands, usign this sentence for Rebuild all option:
cd .. && nmake -f psi\msvc32.mak WIN64= SBR=1 DEVSTUDIO= XCFLAGS=-DGS_THREADSAFE=1 && nmake -f psi\msvc32.mak WIN64= DEVSTUDIO= XCFLAGS=-DGS_THREADSAFE=1 bsc
This approach, rises an error during build:
Error LNK2019 unresolved external symbol errprintf_nomem referenced in
function gs_log_error File \mkromfs.obj 1
As it seems, the file mkromfs.c has a method called errprintf_nomem, which can't be found when GS_THREADSAFE is set.
Questions
1 - Is there any public release of Ghostscript that include x64 DLLs compiled to be THREADSAFE?
And, if not (that's what I'm guessing...)
2 - Is it possible to get this DLL to be THREADSAFE without changing the source code?
3- Could anyone provide, please, a step by step guide or walkthrough to build a x64 Ghostscript DLL using GS_THREADSAFE using Visual Studio (or even any other possible alternative) over Windows 10 x64?
4 - A few posts talk about people achive to manage multithreading using Ghostscript .NET. I assume this examples are all using a GS_THREADSAFE DLL... Is any other workaround we have passed?
Thank a lot in advance.
To summarize all this questions, and as a guide for future developers having this same trouble, these are the answers we've found until now:
AS #KenS mentions in his reply: "No, the Ghostscript developers don't actually build thread-safe versions of the binaries."
At this very moment, clearly not, as it has been reported on this opened bug.
As it seems to be a matter of commercial licensing support, we avoid comment on this point anymore.
Thanks again to #HABJAN. I absolutely take back what I've stated on my question, as it is possible to have Ghostscript .NET working on multi-threading scenarios. Below comes the solution we applied, in case it could be useful for someone.
Based on HABJAN example, what we have done to achieve this was to create a custom class to capture Ghostscript logging:
protected class ConsoleStdIO : Ghostscript.NET.GhostscriptStdIO
{
public ConsoleStdIO(bool handleStdIn, bool handleStdOut, bool handleStdErr) : base(handleStdIn, handleStdOut, handleStdErr)
{
}
public override void StdIn(out string input, int count)
{
char[] userInput = new char[count];
Console.In.ReadBlock(userInput, 0, count);
input = new string(userInput);
}
public override void StdOut(string output)
{
//log
}
public override void StdError(string error)
{
//log
}
}
For our previous method, we simple include a call to this class and this avoids errors when multiple tasks are executed at the same time:
// Define switches...
string[] switchesArray = switches.ToArray();
using (GhostscriptProcessor procesador = new GhostscriptProcessor())
{
try
{
procesador.StartProcessing(switchesArray, new ConsoleStdIO(true, true, true));
byte[] destinationFile = System.IO.File.ReadAllBytes(destinationPath);
return destinationFile;
}
catch (Exception ex)
{
throw ex;
}
finally
{
System.IO.File.Delete(sourceFile);
}
}
Well, it seems to me that you are asking here for technical support.
You clearly want to use Ghostscript in a commercial undertaking, indeed one might reasonably say you want an enterprise version of Ghostscript. Presumably you don't want to alter the source in order to permit you to use an open source license, because you don't want to pay for a commercial license.
With that in mind the answers to your questions are:
No, the Ghostscript developers don't actually build thread-safe versions of the binaries.
Currently, no. That's probably an oversight.
That would be a technical support question, there's no guarantee of technical support to free users, it's the one of the few areas of leverage for dual license vendors to persuade people to take up a commercial license. So I hope you will understand that I'm not going to provide that.
as far as I can see, no.
I'm fairly new to Golang; previously used Python.
I am having difficult time to apply bufio in the object.
type fout struct {
filename string
fo File
bfo Writer
}
func (a *fout) init() {
a.fo,_:=os.Open(a.filename)
a.bfo:=bufio.NewWriter(fo)
}
Basically, I like to create objects; each will have it's filename, and bufio will be used.
Can anyone help me please?
Thank you
Few things in the code sample:
Every use of a name from another package needs to be prefixed with the package name--so fo File has to be fo *os.File.
You normally declare *bufio.Writer and *os.File as pointers (see the bufio and file docs at http://golang.org/pkg)
You want plain =, not :=, for assigning to attributes like a.fo and a.bfo.
Don't throw away errors, particularly if you're used to exceptions, or you'll have impossible-to-debug problems. (For a trivial script for learning you can if err != nil { panic(err) }, but for real use, you almost always want to return them.)
It could also help to review the tour, pick up some tricks/advice from the various talks and blog posts, maybe walk through Go By Example (I admit I haven't persionally used it but sounds like it could be useful when getting started), look at some open-source Go code (projects on Github, the stdlib, anything), and run through the surprisingly readable spec once you're at the level where you want to know how the language really works.
I decided to start a new project to get into hacklang, and after fixing some if the problems I initially ran into transitioning from php habits, I ran into the following errors:
Unbound name: str_replace
Unbound name: empty
Doing some research I found that this is due to using 'legacy' php which isn't typechecked, and will error with //strict.
That's fine and all, empty() was easy enough to replace, however str_replace() is a bit more difficult.
Is there an equivalent function that will work with //strict? Or at least something similar.
I'm aware that I could use //decl but I feel like that defeats the purpose in my case.
Is there at least any way to tell which functions are implemented in hack and which are not in the documentation as I couldn't find one?
For reference (though it isn't too relevant to the question itself), here is the code:
<?hh //strict
class HackMarkdown {
public function parse(string $content) : string {
if($content===null){
throw new RuntimeException('Empty Content');
}
$prepared = $this->prepare($content);
}
private function prepare(string $contentpre) : Vector<string>{
$contentpre = str_replace(array("\r\n","\r"),"\n",$contentpre);
//probably need more in here
$prepared = Vector::fromArray(explode($contentpre,"\n"));
//and here
return $prepared;
}
}
You don't need to change your code at all. You just need to tell the Hack tools about all the inbuilt PHP functions.
The easiest way to do this is to download this folder and put it somewhere in your project. I put it in a hhi folder in the base of my project. The files in there tell Hack about all the inbuilt PHP functions.
Most of them don't have type hints, which can lead to Hack thinking the return type of everything is mixed instead of the actual return, that is actually correct in most cases as, for example, str_replace can return either a string or a bool. However, it does stop the "unbound name" errors, which is the main reason for adding them.
I want to open any file type by using the code below:
System.Diagnostics.Process.Start(pathFile);
Is there a way to check if system application not exist?
for example: pdf, the local machine has no acrobat reader.
I created a try catch, however I'm not satisfied with it, I want to imitate the behavior of windows in opening a file. It has an option of Searching the web / manual search.
try
{
System.Diagnostics.Process.Start(pathFile);
}
catch (System.ComponentModel.Win32Exception ex)
{
composite.ReadingError = ex.Message;
Console.WriteLine("error");
}
You need to use PInvoke (FindExecutable (shell32)):
How to use FindExecutable from C#
If there is no association it should throw a Win32Exception that you could catch.
See here: http://msdn.microsoft.com/en-us/library/53ezey2s.aspx in the exceptions section.
I'm using cucumber to generate test scripts that can be executed by a tool or human... so not the standard use.
However I would like to pass through the scenario and example names through to my output.
Is this possible?
Found it.. (with some help from Tim Walker)
Before do |scenario|
puts "Before Scenario: #{scenario.to_sexp[2]}"
.
.
.
end
Your SExpression may differ, so it's worth doing a scenario.to_sexp.inspect to see what that tree is.
Aslak is keen to avoid exposing properties on his classes (which is a decision I happen to agree with, so I'm happy to do this work around).
A more serious answer (or at least, suggestion): make use of ruby's reflection to try to find what you are looking for. Grab likely objects, find out what methods they have, and see if you can find it. For example:
File.open('happy_hunting.log','a') { |f|
f.print "Scenario supports: #{(scenario.methods - Object.methods).inspect}\n"
}
and then repeat it to figure out whats where.
Another suggestion, look at the source.
I did something scrappy. As I use this info for only debugging, this will work for now, until I find something better.
#Before
public void printTestInfoBeforeScenario(Scenario scenario) {
LOGGER.info("Upcoming Test: "+scenario.getSourceTagNames());
}
#After
public void printTestInfoAfterScenario(Scenario scenario) {
LOGGER.info("Test Complete: " + scenario.getSourceTagNames() + " Status: " + scenario.getStatus());
}