Finally blocks PTIJ Should we be afraid of Artificial Intelligence? We have directed stack trace to standard output in all of our examples. As a part of our sixth example, we'll demonstrate usage of extract_tb(), format_list() and print_list() methods. Those two exceptions are caught in the catch block of this example. Python provides a module named traceback which has a list of method which let us extract error traces, format it and print it according to our need. Have an issue where my application.log is getting filled with errors related to a uri date parser operation that should succeed given a valid yyyyMMdd uri date. * classes to work with files, so attempting to open and read a file can result in both a FileNotFoundException and an IOException. Connect and share knowledge within a single location that is structured and easy to search. How can I recognize one? The StringWriter code prints the following output, which is very readable as stack traces go: To be clear, you dont need this approach when using things like System.out.println or System.err.println; you can just use e.printStackTrace there, which prints to STDERR. acknowledge that you have read and understood our, Data Structure & Algorithm Classes (Live), Data Structure & Algorithm-Self Paced(C++/JAVA), Android App Development with Kotlin(Live), Full Stack Development with React & Node JS(Live), GATE CS Original Papers and Official Keys, ISRO CS Original Papers and Official Keys, ISRO CS Syllabus for Scientist/Engineer Exam, Scala List contains() method with example, Scala Iterator forall() method with example, Scala List takeWhile() method with example, Scala List dropWhile() method with example, Scala Set dropWhile() method with example. The exception in Scala and that results in a value can be pattern matched in the catch block instead of providing a separate catch clause for each different exception. Use ExceptionUtils from Apache Commons Lang: I think you want printStackTrace() rather than getStackTrace. Making statements based on opinion; back them up with references or personal experience. Andrew Grant's answer does not help getting a stack trace of the throwing function, at least not with GCC, because a throw statement does not save the current stack trace on its own, and the catch handler won't have access to the stack trace at that point any more. Asking for help, clarification, or responding to other answers. It contains well written, well thought and well explained computer science and programming articles, quizzes and practice/competitive programming/company interview Questions. Here is an example of the above: Scala Tutorial Learn Scala with Step By Step Guide, Scala String indexOf(String str) method with example, Scala String contentEquals() method with example. Something else? Have you tried setting it to something larger? Explanation. There is three kinds of methods available with the traceback module. How to get an enum value from a string value in Java. Unless you are in danger of running out of disk space, I think #2 is the better option, because if you do have a bug you can go back to the full log and have all the exception history. By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. How do you assert that a certain exception is thrown in JUnit tests? Help me understand the context behind the "It's okay to be white" question in a recent Rasmussen Poll, and what if anything might these results show? I must have missed something, why can't you just catch the exception, and err.out whatever line you like? 542), We've added a "Necessary cookies only" option to the cookie consent popup. There are performance advantages to returning an object instead of making the JVM generate a stack trace.. Below we have explained the usage of the method with simple example. Constructs a new throwable with the specified detail message, cause, suppression enabled or disabled, and writable stack trace enabled or disabled. Below we have again executed code same as the previous cell but this time we have set the limit parameter to 1 hence it only prints the first trace frame. And yes, he spends his leisure time taking care of his plants and a few pre-Bonsai trees. Why does pressing enter increase the file size by 2 bytes in windows, Alternate between 0 and 180 shift at regular intervals for a sine source during a .tran operation on LTspice, First letter in argument of "\affil" not being output if the first letter is "L", Retracting Acceptance Offer to Graduate School. For example, if one out of five methods in your code cause an exception, printStackTrace() will pinpoint the exact line in which the method raised the exception. Article Tags : Picked Scala scala-exception Scala Improve Article It contains well written, well thought and well explained computer science and programming articles, quizzes and practice/competitive programming/company interview Questions. Arrays . Look at the output from our custom exception when we print a stack trace A Java custom exception class To get started, this is pretty much the most simple possible Java custom exception class. Some of them, you almost expect. In the code above, the exception will contain the stack-trace of the first throw-line. Extends for feature (aka mix-in) in Scala is bad practice, isn't it? @paradigmatic made a good point in suggesting to redirect rather than throw the exception; that solves the logging issue. Is there a colloquial word/expression for a push that helps you to start to do something? And, we will use try and catch blocks. What are the consequences of overstaying in the Schengen area by 2 hours? That sort of script typically costs a few minutes of programming in your favorite regex-capable script language. Best practices for handling application specific exceptions? Is there something I can do at this point to grab the stacktrace? This can help with formatting and limiting error trace getting generated. Stack Exchange network consists of 181 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers. Below we have explained the usage of it with simple example. What's the best way to get a stack trace here printed out so I can log and review it to fix errors in my terrible code? When catching an exception, there are two options in case the exception should be rethrown: throw will just rethrow the original exception with the original stack, while throw e would have created a new stack trace. we create an exception object and then we throw it by using throw keyword.Syntax: The try/catch ConstructThe try/catch construct is different in Scala than in Java, try/catch in Scala is an expression. In Scala a single catch block can handle all kinds of exceptions thus providing flexibility. I'm not sure if the request is on the same thread as the error handler, otherwise there might be some answer there. There is already an overload which is accepting 2 parameters, String and Throwable. EDIT To subscribe to this RSS feed, copy and paste this URL into your RSS reader. In Java you do this with a JVM argument: You can set JVM args to be used by Scala by setting an environment variable: Thanks for contributing an answer to Stack Overflow! One drawback of using Scala's wildcard character (_) in a catch clause is that you can't refer to it in your code, such as if you want to print the exception. The only way to deal with the problem - dump raw stacktrace into file/socket and parse it on program restart . The printStackTrace (PrintStream) method writes the stack trace to a file stream. In Scala I used to get the text from a stack trace and then log it like this: In that code, getStackTrace returns a sequence, which I convert to a String before printing it. When and how was it discovered that Jupiter and Saturn are made out of gas? Below we have explained how we can use these methods with a simple example. By using our site, you The output from this new approach is much more readable, as I verified with this little test program: In that code I intentionally wrap an IOException inside a custom exception, which I then throw from my method. I'll tweak log4j and see if I can get this particular error condition logged without the trace. Thus, in Scala, you've got the NoStackTrace: A trait for exceptions which, for efficiency reasons, do not fill in the stack trace. Does the double-slit experiment in itself imply 'spooky action at a distance'? For a moment, lets head over to Stack Overflow - How slow are Java exceptions? Conversely it may be the case that your program is running very low on memory ( 32Mb is the default on a client-class machine by the way) and you have a very deep stack (not uncommon in scala-land!) Why do we kill some animals but not others. How to draw a truncated hexagonal tiling? Consider the situation that you've got a String from some source and you want to get it back into an integer format with Integer.decode. Rethrowing exceptions in Java without losing the stack trace. We'll use the slf4j-simple API as the logging implementation. But when you want to write to a logger, or otherwise convert a stack trace to a string, the second approach works very well. What is a stack trace, and how can I use it to debug my application errors? Here 's a little context to work with: Calling the date parser on an invalid yyyyMMdd string logs 30 line stack trace to the log (this occurs upstream by Play framework/Netty container, better than default 100 line trace): ORIGINAL To prove this, go to http://localhost:8080/errors/throw which has the ErrorController intentionally throw a NullPointerException using the following code: Exception npe = new NullPointerException("Forcing an exception to be thrown"); logger.error("Forcing an exception to be thrown and sent to logging framework",npe); Why does the Angel of the Lord say: you have not withheld your son from me in Genesis? Please make a note that when we used print_exception() method, it printed information about exceptions as well which was not getting printed with print_tb() method. Do flight companies have to make it clear what visas you might need before selling you tickets? Learn in-demand tech skills in half the time. 542), We've added a "Necessary cookies only" option to the cookie consent popup. Other than quotes and umlaut, does " mean anything special? To subscribe to this RSS feed, copy and paste this URL into your RSS reader. Simply override this method in your custom exception class: after adding this method your trace method will not print. Solution The Scala try/catch/ - Selection from Scala Cookbook [Book] . These are situations that are not too dangerous and can be handled by the program. The problem only occurs if I try to access Exception.getStackTrace. 542), We've added a "Necessary cookies only" option to the cookie consent popup. How to measure (neutral wire) contact resistance/corrosion. As usual, if you have any questions, comments, corrections, or better examples, just leave a note in the comments section below. println ("IOException occurred.") println . It contains well written, well thought and well explained computer science and programming articles, quizzes and practice/competitive programming/company interview Questions. It only takes a minute to sign up. printStackTrace outputs to System.err unless you provide a writer. "settled in as a Washingtonian" in Andrew's Brain by E. L. Doctorow, How do I apply a consistent wave pattern along a spiral curve in Geo-Nodes. The main difference is that for consistency, Scala uses the same syntax that match expressions use: case statements to match the different possible exceptions that can occur. Disclaimer Formatting stack traces is a client-side operation and no data will be shared with elmah.io's backend. Another branch, Error are used by the Java run-time system(JVM) to indicate errors having to do with the run-time environment itself(JRE). Stacktrace stacktrace_entry (C++23) basic_stacktrace (C++23) [edit] std::basic_stacktrace Member functions basic_stacktrace::basic_stacktrace (C++23) basic_stacktrace::~basic_stacktrace (C++23) basic_stacktrace::operator= (C++23) basic_stacktrace::current (C++23) basic_stacktrace::get_allocator (C++23) Iterators This question has several ways to convert an exception stack trace to a String. To learn more, see our tips on writing great . This could be from a mistyped variable, incorrect input, or any type of exception that you've defined in your code. Since 2020, hes primarily concentrating on growing CoderzColumn.His main areas of interest are AI, Machine Learning, Data Visualization, and Concurrent Programming. Launching the CI/CD and R Collectives and community editing features for How do you test that a Python function throws an exception? Browse other questions tagged, Where developers & technologists share private knowledge with coworkers, Reach developers & technologists worldwide, Write your code, you may not have printed the stack trace. Full Stack Development with React & Node JS(Live) Java Backend Development(Live) React JS (Basic to Advanced) JavaScript Foundation; Machine Learning and Data Science. Conversely it may be the case that your program is running very low on memory (32Mb is the default on a client-class machine by the way) and you have a very deep stack (not uncommon in scala-land!). Note: At compile time checked exceptions are checked In Java . Matching One or More Exceptions with try/catch Problem You want to catch one or more exceptions in a try/catch block. Active Directory: Account Operators can delete Domain Admin accounts. Is the set of rational points of an (almost) simple algebraic group simple? This makes your code consistent and easier to read, and you dont have to remember a special/different syntax. Are there conventions to indicate a new item in a list? If no such handler exists, the program terminates. (I would NEVER do this, as I would not know when the exception happens and there is no way to track) data.flatMap ( a=> Try (a > 10).toOption) // when the option is None, it will automatically be filtered by the . We provide a versatile platform to learn & code in order to provide an opportunity of self-improvement to aspiring learners. Is it ethical to cite a paper without fully understanding the math/methods, if the math is not relevant to why I am citing it? Why is the Exception thrown in the fist place ? We'll help you or point you in the direction where you can find a solution to your problem. We have then formatted the stack trace. Why do we kill some animals but not others? Find centralized, trusted content and collaborate around the technologies you use most. Ill use Scala code here, but it converts easily to Java. As a part of our ninth example, we'll demonstrate the usage of walk_tb() and StackSummary.extract() methods. To subscribe to this RSS feed, copy and paste this URL into your RSS reader. This method p rints exception information and stack trace entries from traceback object tb to file. Use CRT libraries in your c++ lib file to find out the root cause of the access violation. A great thing about the syntax is that its consistent with the match expression syntax. But when you want to write to a logger, or otherwise convert a stack trace to a string, the second approach works very well. But it doesn't seem to work for me yet. Printing the stack trace of a Log4J exception seems to be something of a trick question. CBSE Class 12 Computer Science; School Guide; All Courses; Tutorials. Exceptions in scala work the same way as in C++ or Java. At program start we check for a file with stacktrace and if it exist - we're writing it in human readable format: Now we'll get the following output on std::terminate call after the program restarts: In a program of mine I'd like to catch all exceptions and explicitly print them (to be able to proceed with finally while still seeing exceptions). The philosophy behind idea #2 is that disk space is cheap, but information can be precious during debug. Normally, use scripts to examine the log after it has been written to disk. As a part of our first example, we'll explain how we can print the stack trace of error using print_tb() method. Connect and share knowledge within a single location that is structured and easy to search. Can a VGA monitor be connected to parallel port? It is a method of Javas throwable class which prints the throwable along with other details like the line number and class name where the exception occurred. Did the residents of Aneyoshi survive the 2011 tsunami thanks to the warnings of a stone marker? Currently the code, when it goes into exception, after printing "My message", also prints the stack trace. 2. I am only interested in printing "My message". Is there a colloquial word/expression for a push that helps you to start to do something? The open-source game engine youve been waiting for: Godot (Ep. We can even generate StackSummary instance from the output of extract_stack() method. Not the answer you're looking for? It certainly seems fishy that getting a stack trace is exhausting your permgen space, but maybe if you can increase the memory to the point where you can actually examine the stack trace you'll be able to get some insight into what's going on. Find centralized, trusted content and collaborate around the technologies you use most. Do flight companies have to make it clear what visas you might need before selling you tickets? How can I get a JavaScript stack trace when I throw an exception? As a part of our thirteenth and last example, we'll demonstrate the usage of walk_stack() method. How can I rethrow an exception in Javascript, but preserve the stack? 542), We've added a "Necessary cookies only" option to the cookie consent popup. as in example? Write a post-processor that filters out the traces from the log file. are patent descriptions/images in public domain? How is "He who Remains" different from "Kang the Conqueror"? How do I read / convert an InputStream into a String in Java? Here is an example of exception Handling using the conventional try-catch block in Scala. The break method uses a ControlThrowable to transfer control up the stack to an enclosing breakable. As a part of this example, we have explained how we can direct the trace generated to a file. Here is an example of exception Handling using the conventional try-catch block in Scala. Is it a logger? Syntax: traceback.print_exc (limit=None, file=None, chain=True) Parameters: This method accepts the following parameters: Connect and share knowledge within a single location that is structured and easy to search. We have explained the usage of extract_stack() with a simple example below. The number of distinct words in a sentence. Browse other questions tagged, Start here for a quick overview of the site, Detailed answers to any questions you might have, Discuss the workings and policies of this site. We'll use our fifth example to demonstrate the usage of print_last() method. Program: // Sum function. Differences between `throw` and `throw new` and exactly how exceptions "bubble up". We'll explain the usage of the method with simple examples. Software Engineering Stack Exchange is a question and answer site for professionals, academics, and students working within the systems development life cycle. What is the ideal amount of fat and carbs one should ingest for building muscle? If a business exception occurs, the default behaviour will be to print the stack trace of that business exception (not the ExecutionException) and return an exit code. It's pointless, as it simply won't work, but regardless, I have MBs of these error traces in my application log. Heres an example of Scalas try/catch syntax. To avoid stack trace in try/except I use print (e) then sys.exit (1) or return 1. Why don't we get infinite energy from a continous emission spectrum? Set the current day's response to i+1. What Does the Stack Trace Look Like? This invocation returns an array of StackTraceElement, from which details about stack frames of the thread can be extracted. EDIT2 Learn more about Stack Overflow the company, and our products. @virtualeyes I've expanded my answer based on the assumption that disk space is not an issue. if you have a script x which calls function y which calls function z which throws an exception, then the first trace element will be 'Y' and . rev2023.3.1.43266. In the excellent book, Programmming Scala, the authors suggest naming your exception variable instead of using the wildcard, which you can then refer to in your own code, something like this: Thanks for contributing an answer to Stack Overflow! As a part of our twelfth example, we have demonstrated the usage of extract_stack() method. Ackermann Function without Recursion or Stack. You can clear out the stack trace in the exception object with, Throw an exception without printing stack trace [closed], The open-source game engine youve been waiting for: Godot (Ep. The StackSummary class has another method named from_list(frame_summary_list) which takes as an input list of FrameSummary instances and generates StackSummary instance from it. What are all the uses of an underscore in Scala? Call GetExceptionInformation in your lib file to get the exception record and the context record. How is "He who Remains" different from "Kang the Conqueror"? As a part of our eleventh example, we have demonstrated the usage of format_stack() method. Also, can you show how to catch multiple exceptions, and just one exception with the Scala wildcard operator (_)? "Had an IOException trying to read that file", "Got some other kind of Throwable exception", // your scala code here, such as closing a database connection, Supplying Default Values for Constructor Parameters, Enumerations (and a Complete Pizza Class), Writing BDD Style Tests with ScalaTest and sbt. But, if you're passing this on up the chain - don't use it - you might just need to log where some exception came from. If you use the standard logger: com.typesafe.scalalogging.Logger , the logger prints the stack trace for you. @larsmans, it's an IllegalArgumentException and I throw it by my own. How to catch and print the full exception traceback without halting/exiting the program? But you really don't care about the stack trace there but its there. In the excellent book, Programmming Scala, the authors suggest naming your exception variable instead of using the wildcard, which you can then refer to in your own code, something like this: As you can see from that code, I just name a variable "unknown", which I can then refer to by name. What are examples of software that may be seriously affected by a time jump? Control resumes with the innermost such handler. Asking for help, clarification, or responding to other answers. If I don't catch exception, it (including stack trace) is printed correctly and looks sane. Please make a note that print_tb() only prints stack trace and does not print actual exception type. Do German ministers decide themselves how to vote in EU decisions or do they have to follow a government line? At a distance ' more, see our tips on writing great String in?!: com.typesafe.scalalogging.Logger, the program # x27 ; s backend without the trace clear. Generated scala print stack trace without exception a file can result in both a FileNotFoundException and an IOException line you like that. Continous emission spectrum the fist place not too dangerous and can be precious during.... Or disabled, and our products answer there and an IOException StackTraceElement, from which details about stack Overflow company. I do n't care about the syntax is that disk space is not an issue try/catch/ - Selection from Cookbook. Can be extracted it contains well written, well thought and well explained science. Point in suggesting to redirect rather than getStackTrace made out of gas R. What are all the uses of an underscore in Scala is bad practice, n't. New ` and exactly how exceptions `` bubble up '' few minutes of programming your. Minutes of programming in your custom exception class: after adding this method your trace method will not actual. Based on the same way as in c++ or Java these are that... Leisure time taking care of his plants and a few pre-Bonsai trees outputs to System.err unless provide... Operators can delete Domain Admin accounts almost ) simple algebraic group simple to redirect rather throw! Rints exception information and stack trace of a stone marker String value Java... Print_Last ( ) with a simple example virtualeyes I 've expanded my answer based on opinion back! Ideal amount of fat and carbs one Should ingest for building muscle override this method p exception! - Selection from Scala Cookbook [ Book ] I read / convert an InputStream into a value. And, we have explained how we can use these methods with a simple example below already overload. A colloquial word/expression for a push that helps you to start to do something overload which accepting. Is printed correctly and looks sane a post-processor that filters out the traces from log! Log4J and see if I can do at this point to grab stacktrace... Out of gas answer there consistent and easier to read, and our products do! An ( almost ) simple algebraic group simple exceptions, and students working within systems! Is there a colloquial word/expression for a moment, lets head over to Overflow... Generated to a file and paste this URL into your RSS reader CRT libraries in your custom exception class after. Youve been waiting for: Godot ( Ep share knowledge within a single catch block can handle kinds... A continous emission spectrum scripts to examine the log file few pre-Bonsai trees lib file to get exception! ; back them up with references or personal experience Scala Cookbook [ Book ] and umlaut, does `` anything! Of rational points of an ( almost ) simple algebraic group simple a String in. Selection from Scala Cookbook [ Book ] context record block can handle all kinds of exceptions thus flexibility! To start to do something be some answer there the syntax is that disk space is not an.... And read a file time jump that its consistent with the match syntax. Print_Tb ( ) method launching the CI/CD and R Collectives and community editing features how., and you dont have to make it clear what visas you might need before selling you?. It with simple examples visas you might need before selling you tickets read a stream! Walk_Tb ( ) method new item in a try/catch block n't catch,. It with simple examples trace method will not print actual exception type note that print_tb ( ) method can this. But it converts easily to Java and share knowledge within scala print stack trace without exception single that! Catch multiple exceptions, and our products easy to search about stack frames of the method with simple.... Idea # 2 is that disk space is cheap, but information can be handled by program... Time checked exceptions are caught in the direction where you can find a solution to problem. About the syntax is that its consistent with the match expression syntax c++ or Java read... Collectives and scala print stack trace without exception editing features for how do I read / convert an InputStream into a value. The printStackTrace ( ) and StackSummary.extract ( ) method versatile platform to learn more about frames! Prints stack trace there but its there of exceptions thus providing flexibility override this method your method... It 's an IllegalArgumentException and I throw it by my own it doesn #. Trace there but its there single location that is structured and easy to search compile time checked exceptions checked... ( _ ) throw it by my own print ( e ) then sys.exit ( 1 ) return. Fifth example to demonstrate the usage of format_stack ( ) method is practice. Lib file to find out the root cause of the first throw-line carbs scala print stack trace without exception Should ingest building! Scala code here, but information can be extracted Commons Lang: I think you want printStackTrace ( ) StackSummary.extract. Do n't we get infinite energy from a String in Java expanded my answer based on ;! Exceptions in Java to measure ( neutral wire ) contact resistance/corrosion to measure neutral. Are checked in Java without losing the stack slf4j-simple API as the logging implementation of his plants and a pre-Bonsai! Your RSS reader articles, quizzes and practice/competitive programming/company interview Questions and read a file result... Time taking care of his plants and a few minutes of programming in your favorite regex-capable language! Occurred. & quot ; ) println action at a distance ' throw ` and exactly how exceptions `` bubble ''... To measure ( neutral wire ) contact resistance/corrosion 12 computer science and programming,... Handling using the conventional try-catch block in Scala # x27 ; s response to i+1 script typically costs a minutes. Error trace getting generated an ( almost ) simple algebraic group simple try/catch block School Guide ; all Courses Tutorials! Follow a government line is `` He who Remains '' different from `` the! Work the same thread as the logging implementation good point in suggesting to redirect than... Throwable with the problem - dump raw stacktrace into file/socket and parse it on program restart a list this your! 1 ) or return 1 the Scala try/catch/ - Selection from Scala Cookbook [ Book.. Fist place, use scripts to examine the log file '' option to the cookie consent popup spends his time... As the logging issue of walk_stack ( ) method returns an array StackTraceElement! Contact resistance/corrosion logger prints the stack trace for you point you in the code above, exception. Code in order to provide an opportunity of self-improvement to aspiring learners trace you... ) contact resistance/corrosion up the stack trace and does not print actual exception type behind idea 2. Print ( e ) then sys.exit ( 1 ) or return 1 my application errors get the record... The Scala try/catch/ - Selection from Scala Cookbook [ Book ] (.! Is an example of exception Handling using the conventional try-catch block in Scala is bad practice, is n't?... At this point to grab the stacktrace do you assert that a exception! Demonstrate the usage of format_stack ( ) methods ; that solves the logging implementation, can you show how get. Regex-Capable script language, or responding to other answers Overflow - how slow are Java exceptions already an overload is! Attempting to open and read a file stream, lets head over to stack the. All the uses of an ( almost ) simple algebraic group simple method will not print actual exception.! To start to do something my answer based on scala print stack trace without exception ; back them up with or... Exceptions with try/catch problem you want to catch one or more exceptions with try/catch you! Contact resistance/corrosion or personal experience without halting/exiting the program to stack Overflow the company, and you dont have make!: at compile time checked exceptions are checked in Java without losing the stack trace there but its there work... To open and read a file can result in both a FileNotFoundException and IOException! Limiting error trace getting generated order to provide an opportunity of self-improvement to learners. Libraries in your custom exception class: after adding this method your method! Conqueror '' a new throwable with the problem - dump raw stacktrace into file/socket and parse it on restart! Two exceptions are caught in the Schengen area by 2 hours the context record the of. Are checked in Java animals but not others file stream your code consistent and easier to,. `` Necessary cookies only '' option to the warnings of a log4j seems... And StackSummary.extract ( ) with a simple example or personal experience ( including stack trace entries from object. Explained the usage of the access violation operator ( _ ) prints stack for! To learn more about stack frames of the method with simple example the code,! Get infinite energy from a String value in Java without losing the stack trace entries from traceback tb... The technologies you use most can be handled by the program n't you catch! Data will be shared with elmah.io & # x27 ; ll use the standard logger: com.typesafe.scalalogging.Logger, exception. Compile time checked exceptions are checked in Java you to start to something! Logged without the trace stack to an enclosing breakable we can even StackSummary. 'Spooky action at a distance ' a stone marker consistent with the specified detail message, cause suppression! Of walk_stack ( ) method writes the stack trace when I throw it by my own and print the exception... Pre-Bonsai trees ; ) println exception type paste this URL into your reader.