I have the same version of JDK on my laptop and my desktop. My laptop is Windows 7 and my desktop is Windows XP. When I run my game on the desktop, it says cannot find or load main class client. When I run it on my laptop it finds it. I have the versions for java and jdk 1.7u4 set up correctly for each computer. And when I compile the game, I have errors on the desktop that I don't get on the laptop. I would post my code, but I know it's not a coding error, because it works on one computer, yet not the other one. I've checked all details a million times, even tried fixing the random false errors I get from compiling, but have had no progress. I don't want to always have to edit my game client off of my laptop because I host the game on my desktop. If anyone has had this problem before, please tell me how you solved it. If you've had it but can't solve it, at least let me know I'm not the only one this has happened to. I can't find any solutions with Google, and I've even tried using a different version of JDK.(1.7u1) So, if it's not java, it's not my game, it has to be my computer. What could cause my computer to act like this towards my game. And other things compile fine, it's just my game client that doesn't compile. So then again, would it be something about my game, even though it works on my laptop and use to work on my desktop?? This is so confusing.
In case it is because of my client, and now that I read over the compiler a few times again, it may be. So here are the errors:
.\Javafiles\MP3.java:5: error: package javazoom.jl.player does not exist
import javazoom.jl.player.Player;
^
.\Javafiles\MID.java:5: error: package javazoom.jl.player does not exist
import javazoom.jl.player.Player;
^
.\Javafiles\MP3.java:20: error: cannot find symbol
player.close();
^
symbol: method close()
location: variable player of type Player
.\Javafiles\MP3.java:32: error: constructor Player in class Player cannot be app
lied to given types;
player = new Player(bis);
^
required: no arguments
found: BufferedInputStream
reason: actual and formal argument lists differ in length
.\Javafiles\MP3.java:42: error: cannot find symbol
try { player.play(); }
^
symbol: method play()
location: variable player of type Player
.\Javafiles\MID.java:18: error: cannot find symbol
public void close() { if (player != null) player.close(); }
^
symbol: method close()
location: variable player of type Player
.\Javafiles\MID.java:27: error: constructor Player in class Player cannot be app
lied to given types;
player = new Player(bis);
^
required: no arguments
found: BufferedInputStream
reason: actual and formal argument lists differ in length
.\Javafiles\MID.java:37: error: cannot find symbol
try { player.play(); }
^
symbol: method play()
location: variable player of type Player
Note: .\Javafiles\client.java uses unchecked or unsafe operations.
Note: Recompile with -Xlint:unchecked for details.
8 errors
Press any key to continue . . .
The compiler complains that it can't find the required class javazoom.jl.player.Player on the classpath. There must be a difference in the way you compile the application on the two different machines.
Don't look at different operating systems or Java SDK versions. Check the build process. Verify that you have the required library on both machines and the classpaths point to that jar file.
Further Reading
The import javazoom cannot be resolved
Related
I have been facing issues with using boost::asio::io_service::run in Linux, very very similar to this: creating a boost::asio worker thread with boost::thread under linux.
I see that the answer for that question is
"The error is be that boost::asio::io_service::run is overloaded, in which case you have to resolve the ambiguity."
Can someone tell me how does one resolve this ambiguity for it? Thanks.
I am in RHEL 7.7, coding using an Eclipse IDE. My Code segment is:
std::vector<boost::thread> threadPool;
boost::assio::io_service IOService;
.
.
threadPool.pushback(boost::thread(boost::bind(&boost::asio::io_service::run, &IOService)));
I get the error "Invalid overload of 'boost::asio::io_service::run' "
I see that boost::asio::io_service::run has two overloads:
std::size_t boost::asio::io_service::run()
std::size_t boost::asio::io_service::run(boost::system::error_code &ec)
I don't know how to resolve the ambiguity as they have the same return. If I try to add in a variable like this:
threadPool.pushback(boost::thread(boost::bind(&boost::asio::io_service::run(), &IOService)));
I get the error:
"Invalid Arguments 'Candidates are unsigned long int run()' "
and I don't know what to do.
Can someone teach a confused idiot like me what should i do? Is it an environment problem, a linking problem or a declaration problem?
EDIT 1: Using lambdas gives the error
'Address of overloaded function with no contextual type information'
which makes no sense and I assume is merely reiterating the ambiguity of the function.
This error does not show up in the Console window, which details the results of the Make, only in the Errors window. This makes me think it purely a IDE syntax check type error? GCC version is 4.8.5.
This is meant to be a FAQ question, so please be as complete as possible. The answer is a community answer, so feel free to edit if you think something is missing.
This question was discussed and approved on meta.
I am using R and tried some.function but I got following error message:
Error: could not find function "some.function"
This question comes up very regularly. When you get this type of error in R, how can you solve it?
There are a few things you should check :
Did you write the name of your function correctly? Names are case sensitive.
Did you install the package that contains the function? install.packages("thePackage") (this only needs to be done once)
Did you attach that package to the workspace ?
require(thePackage) (and check its return value) or library(thePackage) (this should be done every time you start a new R session)
Are you using an older R version where this function didn't exist yet?
Are you using a different version of the specific package? This could be in either direction: functions are added and removed over time, and it's possible the code you're referencing is expecting a newer or older version of the package than what you have installed.
If you're not sure in which package that function is situated, you can do a few things.
If you're sure you installed and attached/loaded the right package, type help.search("some.function") or ??some.function to get an information box that can tell you in which package it is contained.
find and getAnywhere can also be used to locate functions.
If you have no clue about the package, you can use findFn in the sos package as explained in this answer.
RSiteSearch("some.function") or searching with rdocumentation or rseek are alternative ways to find the function.
Sometimes you need to use an older version of R, but run code created for a newer version. Newly added functions (eg hasName in R 3.4.0) won't be found then. If you use an older R version and want to use a newer function, you can use the package backports to make such functions available. You also find a list of functions that need to be backported on the git repo of backports. Keep in mind that R versions older than R3.0.0 are incompatible with packages built for R3.0.0 and later versions.
Another problem, in the presence of a NAMESPACE, is that you are trying to run an unexported function from package foo.
For example (contrived, I know, but):
> mod <- prcomp(USArrests, scale = TRUE)
> plot.prcomp(mod)
Error: could not find function "plot.prcomp"
Firstly, you shouldn't be calling S3 methods directly, but lets assume plot.prcomp was actually some useful internal function in package foo. To call such function if you know what you are doing requires the use of :::. You also need to know the namespace in which the function is found. Using getAnywhere() we find that the function is in package stats:
> getAnywhere(plot.prcomp)
A single object matching ‘plot.prcomp’ was found
It was found in the following places
registered S3 method for plot from namespace stats
namespace:stats
with value
function (x, main = deparse(substitute(x)), ...)
screeplot.default(x, main = main, ...)
<environment: namespace:stats>
So we can now call it directly using:
> stats:::plot.prcomp(mod)
I've used plot.prcomp just as an example to illustrate the purpose. In normal use you shouldn't be calling S3 methods like this. But as I said, if the function you want to call exists (it might be a hidden utility function for example), but is in a namespace, R will report that it can't find the function unless you tell it which namespace to look in.
Compare this to the following:
stats::plot.prcomp
The above fails because while stats uses plot.prcomp, it is not exported from stats as the error rightly tells us:
Error: 'plot.prcomp' is not an exported object from 'namespace:stats'
This is documented as follows:
pkg::name returns the value of the exported variable name in namespace pkg, whereas pkg:::name returns the value of the internal variable name.
I can usually resolve this problem when a computer is under my control, but it's more of a nuisance when working with a grid. When a grid is not homogenous, not all libraries may be installed, and my experience has often been that a package wasn't installed because a dependency wasn't installed. To address this, I check the following:
Is Fortran installed? (Look for 'gfortran'.) This affects several major packages in R.
Is Java installed? Are the Java class paths correct?
Check that the package was installed by the admin and available for use by the appropriate user. Sometimes users will install packages in the wrong places or run without appropriate access to the right libraries. .libPaths() is a good check.
Check ldd results for R, to be sure about shared libraries
It's good to periodically run a script that just loads every package needed and does some little test. This catches the package issue as early as possible in the workflow. This is akin to build testing or unit testing, except it's more like a smoke test to make sure that the very basic stuff works.
If packages can be stored in a network-accessible location, are they? If they cannot, is there a way to ensure consistent versions across the machines? (This may seem OT, but correct package installation includes availability of the right version.)
Is the package available for the given OS? Unfortunately, not all packages are available across platforms. This goes back to step 5. If possible, try to find a way to handle a different OS by switching to an appropriate flavor of a package or switch off the dependency in certain cases.
Having encountered this quite a bit, some of these steps become fairly routine. Although #7 might seem like a good starting point, these are listed in approximate order of the frequency that I use them.
If this occurs while you check your package (R CMD check), take a look at your NAMESPACE.
You can solve this by adding the following statement to the NAMESPACE:
exportPattern("^[^\\\\.]")
This exports everything that doesn't start with a dot ("."). This allows you to have your hidden functions, starting with a dot:
.myHiddenFunction <- function(x) cat("my hidden function")
I had the error
Error: could not find function some.function
happen when doing R CMD check of a package I was making with RStudio. I found adding
exportPattern(".")
to the NAMESPACE file did the trick. As a sidenote, I had initially configured RStudio to use ROxygen to make the documentation -- and selected the configuration where ROxygen would write my NAMESPACE file for me, which kept erasing my edits. So, in my instance I unchecked NAMESPACE from the Roxygen configuration and added exportPattern(".") to NAMESPACE to solve this error.
This error can occur even if the name of the function is valid if some mandatory arguments are missing (i.e you did not provide enough arguments).
I got this in an Rcpp context, where I wrote a C++ function with optionnal arguments, and did not provided those arguments in R. It appeared that optionnal arguments from the C++ were seen as mandatory by R. As a result, R could not find a matching function for the correct name but an incorrect number of arguments.
Rcpp Function : SEXP RcppFunction(arg1, arg2=0) {}
R Calls :
RcppFunction(0) raises the error
RcppFunction(0, 0) does not
Rdocumentation.org has a very handy search function that - among other things - lets you find functions - from all the packages on CRAN, as well as from packages from Bioconductor and GitHub.
If you are using parallelMap you'll need to export custom functions to the slave jobs, otherwise you get an error "could not find function ".
If you set a non-missing level on parallelStart the same argument should be passed to parallelExport, else you get the same error. So this should be strictly followed:
parallelStart(mode = "<your mode here>", N, level = "<task.level>")
parallelExport("<myfun>", level = "<task.level>")
You may be able to fix this error by name spacing :: the function call
comparison.cloud(colors = c("red", "green"), max.words = 100)
to
wordcloud::comparison.cloud(colors = c("red", "green"), max.words = 100)
I got the same, error, I was running version .99xxx, I checked for updates from help menu and updated My RStudio to 1.0x, then the error did not come
So simple solution, just update your R Studio
I am working on a legacy Ada 95 project inherited from another company. I have recently upgraded our compiler from Gnat 3.13a1 to Gnat 4.7.4. The program still compiles, but one of the tasks is crashing due to a Constraint_Error.
Process_Ua(Buffer, Msg_Kind);
Tr_Log5("MSG KIND IS: " & Message_Received_Type'Image(Msg_Kind));
The Constraint_Error occurs on the second line above, with the message "Invalid Data." Msg_Kind is of type Message_Received_Type (which is an enum type), and it is properly initialised at the start of this subprogram, so I'm having trouble understanding how the data could be invalid, when assigning anything that isn't of Message_Received_Type to Msg_Kind would result in a Constraint_Error when that occurs.
Invalid_Data is always the sign of an uninitialized variable.
I presume you are compiling with -gnatVa and pragma Initialize_Scalars (which you have put in a gnat.adc file or in a file referenced from your project's Builder'Global_Configuration_Pragmas attribute).
In such a case, the compiler tries to initialize the variables with an invalid value (outside of the valid range), and adds additional checks. When the checks fail, they raise the Invalid_Data exception.
Perhaps the older compiler was always initializing an out parameter (but that would be surprising, how would it chose the default value) ?
I've got a TypeScript script that has to interact with a third-party vendor that uses global functions as callbacks (you can't pass in a callback). For instance, to "listen" for a result from their "API", you define the function SetElqContent. E.g.,
window.SetElqContent = function(){/* handle result */};
When the TypeScript compiler sees this line, it complains that The property 'SetElqContent' does not exist on value of type 'Window'.
I thought I could get around this by simply casting to type "any". Actually, this isn't type casting but type assertion, but I think of it as casting, although I understand it's not quite the same. So, I tried:
(<any>window).SetElqContent = function(){/* handle result */};;
To m y surprise, this results in Syntax error, and the line number and column points to the < character in the <any> cast. I tried a few other variants, and I get Syntax error on the initial < of the cast no matter what kind of cast I was doing:
var windowAny = <any>window;
var docElement = <HTMLElement>window.document;
What is it about my type assertions that is invalid syntax?
I'm using Visual Studio 2013 with Update 2, which has a "compile on save" feature for TypeScript files. That's how I'm compiling my .ts files, and it's from in Visual Studio where the Syntax error message is emitted.
UPDATE: Apparently this is related to Visual Studio. When I use the standalone tsc compiler to compile the same file, it emits no errors or warnings.
Apparently my syntax is correct but there is a bug in the Visual Studio tooling. I can't provide exact reproduce steps, and in fact, deleting everything in the .ts file, saving, then restoring the code (via ctrl-z) and resaving caused the "syntax error" warning to disappear.
If I can determine any more specifics about what causes this issue to manifest, I'll report back.
Best way is to create a type definitions file for it
If the library name is eloqua.js, you create a eloqua.d.ts file and refer to it in your .js file like
/// < reference path="../typings/eloqua.d.ts" />
There are many type definition files online available at definitelyTyped website.
https://github.com/borisyankov/DefinitelyTyped
You can contribute yours to there as well.
If you extend the Window interface definition, you'll remove the error:
interface Window {
SetElqContent: Function;
}
window.SetElqContent = function(){/* handle result */};
Here is how you can do the assertion properly:
function SetElqContent(){/* handle result */};
// FINE
(<any>window).SetElqContent = SetElqContent;
or
// FINE
(<any>window).SetElqContent = function SetElqContent(){/* handle result */};
However you should avoid asserting and just do what Steve Fenton recommends as it is more discoverable
Update
Demo in VS:
Basically, I'm trying to understand the difference between the "Break in Class Module" and "Break on Unhandled Errors" that appear in the Visual Basic 6.0 IDE under the following path:
Tools --> Options --> General --> Error Trapping
The three options appear to be:
Break on All Errors
Break in Class Module
Break on Unhandled Errors
Now, apparently, according to MSDN, the second option (Break in Class Module) really just means "Break on Unhandled Errors in Class Modules". Also, this option appears to be set by default (ie: I think its set to this out of the box).
What I am trying to figure out is, if I have the second option selected, do I get the third option (Break on Unhandled Errors) for free? In that, does it come included by default for all scenarios outside of the Class Module spectrum? To advise, I don't have any Class Modules in my currently active project. I have .bas modules though. Also, is it possible that by Class Mdules they may be referring to normal .bas Modules as well? (this is my second sub-question).
Basically, I just want the setting to ensure there won't be any surprises once the exe is released. I want as many errors to display as possible while I am developing, and non to be displayed when in release mode. Normally, I have two types of On Error Resume Next on my forms where there isn't explicit error handling, they are as follows:
On Error Resume Next ' REQUIRED
On Error Resume Next ' NOT REQUIRED
The required ones are things like, checking to see if an array has any length, if a call to its UBound errors out, that means it has no length, if it returns a value 0 or more, then it does have length (and therefore, exists). These types of Error Statements need to remain active even while I am developing. However, the NOT REQUIRED ones shouldn't remain active while I am developing, so I have them all commented out to ensure that I catch all the errors that exist.
Once I am ready to release the exe, I do a CTRL+H to find all occurrences of:
'On Error Resume Next ' NOT REQUIRED
(You may have noticed they are commented out)... And replace them with:
On Error Resume Next ' NOT REQUIRED
... The uncommented version, so that in release mode, if there are any leftover errors, they do not show to users.
For more on the description by MSDN on the three options (which I've read twice and still don't find adequate) you can visit the following link:
http://webcache.googleusercontent.com/search?q=cache:yUQZZK2n2IYJ:support.microsoft.com/kb/129876&hl=en&lr=lang_en%7Clang_tr&gl=au&tbs=lr:lang_1en%7Clang_1tr&prmd=imvns&strip=1
I’m also interested in hearing your thoughts if you feel like volunteering them (and this would be my tentative/totally optional third sub-question, that being, your thoughts on fall-back error handling techniques).
Just to summarize, the first two questions were, do we get option 3 included in all non-class scenarios if we choose option 2? And, is it possible that when they use the term "Class Module" they may be referring to .bas Modules as well? (Since a .bad Module is really just a class module that is pre-instantiated in the background during start-up).
Thank you.
I'll start with the first option. Break on all errors simply disables your error handlers. This is useful when you are attempting to debug after you've put in error handlers, because you can have errors in the handlers themselves, or you can lose track of where the error happened when the error bubbles up the containership heirarchy (errors that aren't handled in a procedure attempt to find a handler in a calling procedure, which can be confusing if you're trying to find the offending line of code).
Next, break on unhandled errors doesn't actually break in a class module if there is a line of code causing an error in there. If you have this option set, and you call a method in a class, and there's an error in the line of code in the method, you'll break on the line in your client that has the method call.
Break in class module goes to the line of code in the class that has the error. A caveat to this is that if you are working with an ActiveX EXE, the controlling setting is in its project rather than in the client project. That is, you can have break on all errors set in your client project, and break on unhandled errors set in your ActiveX EXE project, and you won't break in the class module because you are working with two separate processes.
I prefer personally to leave it set on break in class module, because it lets me drill down to the site of the error with greatest precision. This is before I start doing error handlers, though; at that point I generally bounce around all three, depending on what I'm trying to stabilize.
Finally, I do NOT recommend EVER using On Error Resume Next except in the context of inline error handling.
Yes, when you select "Break in class module", it DOES still break on unhandled errors, but it will also break on ANY errors in class modules (not plain modules) that aren't handled in the class module itself.
Contrast this to "break on unhandled errors" which will cause it to exit out of the class/user control code when an error occurs inside it making it difficult to track down the exact location.
It's probably best to leave it set on the "break on unhandled errors" for general development as the others WILL get annoying when you have handled errors that are benign. Note that it's best to try and detect these before they trigger an error though.