exception

问题 I am trying to filter HTTP Get request packets using scapy by using the Raw information of the packet for deciding which packet is a Get request and which isn't but I didn't find a way to decode the Raw section of the packet, something that looks like that (Not sure if that packet is a HTTP Get request): <Raw `load="\x17\x03\x03\x00m\xb8G\xdb\n\xff\x94s\x90y\xe3y\xfa\xa1\x81[-\x05\xf8'Jpq\xf3\x98\xa0\x04d\x08N\xf6\x08\x93\xb1\xd9\xed\xc4^;\xc15\xf2D\xa7\xb4_\x95\x8f\x14l5~[9\xb0\x9f^EI\xbb

问题 I've been working on my final project for my AP Computer Science class and am modifying the AP Picture Lab to do it (all of the source code is available at https://github.com/jvperrin/ap-picture-lab). For one portion of my project, I implement a depth first search to get adjacent pixels to the target pixel that are black. However, it seems like every other time I run the program I either get a stack overflow error or the program works perfectly. Is there a reason I'm getting this problem?

问题 I googled a lot and almost all examples I found used exception handling in Controller with own Exception Handler. I always thought this should be done on service layer of program. If not, I really don't understand the reason to create separate service layer. Also, if I implement my exception handling in Controller, does it mean that I must throw exception in all the previous layers? 回答1: Unless you can recover from an error condition, you'll have to let your exceptions pop all the way up to

问题 I googled a lot and almost all examples I found used exception handling in Controller with own Exception Handler. I always thought this should be done on service layer of program. If not, I really don't understand the reason to create separate service layer. Also, if I implement my exception handling in Controller, does it mean that I must throw exception in all the previous layers? 回答1: Unless you can recover from an error condition, you'll have to let your exceptions pop all the way up to

问题 Based on this question (What benefit does the new Exception filter feature provide?). The statement: Exception filters are preferable to catching and rethrowing because they leave the stack unharmed. If the exception later causes the stack to be dumped, you can see where it originally came from, rather than just the last place it was rethrown. after doing some testing, I did not see the difference between both, the old and the new, I still see the exception from the place it was rethrown . So

问题 I'm trying to append information to an existing Excel file, but I keep receiving java.lang.NullPointerException. Please refer to the code and exception message below. Code : private WritableSheet appendingSheet; private static File report; public void AppendToDoc (String path) throws IOException, WriteException, BiffException { this.inputFile = path; report = new File(inputFile); Workbook appendingWorkbook = Workbook.getWorkbook(new File(inputFile)); WritableWorkbook copy = Workbook

问题 I'm trying to append information to an existing Excel file, but I keep receiving java.lang.NullPointerException. Please refer to the code and exception message below. Code : private WritableSheet appendingSheet; private static File report; public void AppendToDoc (String path) throws IOException, WriteException, BiffException { this.inputFile = path; report = new File(inputFile); Workbook appendingWorkbook = Workbook.getWorkbook(new File(inputFile)); WritableWorkbook copy = Workbook

问题 I am currently trying to implement a customized error handler for spring boot and I have done it with the following: public class ExceptionHandler extends HandlerInterceptorAdapter { public static Logger log = LoggerFactory.getLogger(LoggingInterceptor.class); public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, @Nullable ModelAndView modelAndView) throws Exception { try { log.info("Service {} Calling {} on {} finished with status {}",request

问题 I am currently trying to implement a customized error handler for spring boot and I have done it with the following: public class ExceptionHandler extends HandlerInterceptorAdapter { public static Logger log = LoggerFactory.getLogger(LoggingInterceptor.class); public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, @Nullable ModelAndView modelAndView) throws Exception { try { log.info("Service {} Calling {} on {} finished with status {}",request

问题 Is it fine to throw an exception on the server side when the requested resource was not found? the client receives a 404 not found. My concern is whether it is fine/wrong to throw an exception on the server side when this happens. 回答1: It's hard to assume what your are trying to do with the level of details you added to your question. However, if you handle the exceptions properly, there may be nothing wrong with that approach. Have a look at the approaches used by some frameworks: JAX-RS You