catch-block

问题 In my main tcl script, I am calling a tcl proc wrapped in a catch command. This proc in-turn calls 10 more procs. When there is an error in execution in any of those 10 procs, TCL still continues execution of my main script as expected and I am just able to view the error message which I captured. This error message may/may-not be conclusive enough to determine which of the 10 procs errored out during execution. Is there a way to still keep capturing all the stdout until the point of error? I

问题 I have the below code with which i am able to print the fullclassname,classname,methodname, at which error occured. Also, I am able to print Line-Number but the Line-Number printed is the line at which the variable "LineNumber" is initialized. How can i print the exact LineNumber and ColumnNumber in try block at which error occured? try { SQL Query } catch(Exception e) { String fullClassName = Thread.currentThread().getStackTrace()[1].getClassName(); String className = fullClassName.substring

问题 In the try catch statement we can do: try{} catch(...){} As far as I know, ... means any exception. My question is : Why the C++ standard chose this way (...) instead of just () ? while, for example, in functions if you do not need parameters you just put () : void foo(); Is it related to variadic templates in any way? 回答1: catch() would imply strongly that nothing was passed to that particular catch block. But that is not true, catch(...){ throw; } actually re-throws the exception caught by

问题 I wrote a piece of code to catch specific exception with help from this link. It is like: catch (SQLException sqle) { // TODO Auto-generated catch block String sqlMessage = sqle.getMessage(); String sqlState = sqle.getSQLState(); int vendorCode = sqle.getErrorCode(); System.out.println("Exception occurred:"); System.out.println("Message: " + sqlMessage); System.out.println("SQL state: " + sqlState); System.out.println("Vendor code: " + vendorCode); } But I am getting output as: java.sql

问题 Consider the following C++ code: class MyException {}; void someFunction() { try { /// ... code that may throw } catch(std::exception& e ) { throw MyException(); } } Question Is the exception e absorbed at the beginnging of the catch block or at the end of the catch block? In the second case throwing the new exception would result in having two exceptions in flight, what is not what I want. I want to absorb the std::exception and start one of my own type. 回答1: No. That's how one should do it.

问题 There are certain predefined exceptions in Java, which, if thrown, report that something serious has happened and you'd better improve your code, than catching them in a catch block (if I have understood it correctly). But still I find many programs in which I have the following: } catch (IOException e) { ... } catch (FileNotFoundException e) { .... } and I thought that IOException and FileNotFoundException are exactly such kind of exceptions, which we shouldn't catch in a catch block. Why

问题 I have seen some developers use the return statement in a catch block. Why/when would this be a useful technique to employ? EDIT: I actually just saw the return keyword being used. Thanks 回答1: public void Function() { try { //some code here } catch { return; } } when return; is hit, the execution flow jumps out of the function. This can only be done on void methods. EDIT: you do this if you dont want to execute the rest of the function. For example if you are doing file IO and a read error

问题 What's the general difference between these two styles of handling .catch blocks in Promises: ... .catch(e => myMethod(e)) ... .catch(myMethod) What does a Promise's .catch pass to the receiving method? e.g. Can there be additional arguments? 回答1: In both cases, there is only one argument. There's no fundamental difference between these two styles, except that an arrow function behaves differently than a real function , especially this will be undefined or window (depending on whether strict

问题 What's the difference between the following catch blocks? try { ... } catch { ... } and try { ... } catch(Exception) { ... } I realize, in either case, the exception instance is not available but is there anything that I can do with one that is not possible with the other? 回答1: They are almost the same. From the C# Language Specification, section 8.10: Some programming languages may support exceptions that are not representable as an object derived from System.Exception, although such

问题 Is the ANR an exception, an error or what? Can we actually catch it in a try{} catch(){} structure? 回答1: ANR (Application Not Responding) is not exactly an error. It is shown when your application is very sluggish and takes a lot of time to respond, thus making the user wait. The user won't appreciate if your application makes them wait for a long time. So, the Android framework gives the user an option of closing your application. http://developer.android.com/guide/practices/design