There are two issues in your code: Consider this: This simplified piece of code throws Cannot perform runtime binding on a null reference since speakers is not defined (null reference). You can fix it by defining speakers in the dynamic ViewBag before the loop: The second issue: speakers in your code is a List, you might want to define ViewBag.speakers as a List<List<string>> and call .Add(speakers) instead … Read more
Here is the complete source code, updated from your source:
I am using apache commons http client to call url using post method to post the parameters and it is throwing the below error rarely. Can someone suggest what is causing this Exception and how to debug it?
Well then: welcome to the R world 😉 Here you go Setting up the code Applying the code Investigating the output Additional remarks tryCatch tryCatch returns the value associated to executing expr unless there’s an error or a warning. In this case, specific return values (see return(NA) above) can be specified by supplying a respective handler function (see arguments error and warning in ?tryCatch). These … Read more
You’ve added an extra level of abstraction by calling the method with reflection. The reflection layer wraps any exception in an InvocationTargetException, which lets you tell the difference between an exception actually caused by a failure in the reflection call (maybe your argument list wasn’t valid, for example) and a failure within the method called. Just unwrap the … Read more
On Python ≥ 3.5, use pathlib.Path.mkdir: For older versions of Python, I see two answers with good qualities, each with a small flaw, so I will give my take on it: Try os.path.exists, and consider os.makedirs for the creation. As noted in comments and elsewhere, there’s a race condition – if the directory is created between the os.path.exists and the os.makedirs calls, the os.makedirs will … Read more
After you compile your code, you end up with .class files for each class in your program. These binary files are the bytecode that Java interprets to execute your program. The NoClassDefFoundError indicates that the classloader (in this case java.net.URLClassLoader), which is responsible for dynamically loading classes, cannot find the .class file for the class that you’re trying to use. Your code … Read more
On Python ≥ 3.5, use pathlib.Path.mkdir: For older versions of Python, I see two answers with good qualities, each with a small flaw, so I will give my take on it: Try os.path.exists, and consider os.makedirs for the creation. As noted in comments and elsewhere, there’s a race condition – if the directory is created … Read more
Assume you were: Reading a network file and got disconnected. Reading a local file that was no longer available. Using some stream to read data and some other process closed the stream. Trying to read/write a file, but don’t have permission. Trying to write to a file, but disk space was no longer available. There … Read more