It seems to be impossible to make a cached thread pool with a limit to the number of threads that it can create. Here is how static Executors.newCachedThreadPool is implemented in the standard Java library: So, using that template to go on to create a fixed sized cached thread pool: Now if you use this and su…
Tag: java
Java – find the first cause of an exception
I need to check if an exception is caused by some database problem. I receive an Exception and check if its cause contains the “ORA” string and return that (something like “ORA-00001”). The problem here is that the exception I receive is nested inside other exceptions, so if I don̵…
Using Mockito’s generic “any()” method
I have an interface with a method that expects an array of Foo: I am mocking this interface using Mockito, and I’d like to assert that doStuff() is called, but I don’t want to validate what argument are passed – “don’t care”. How do I write the following code using any(), t…
Growing ByteBuffer
Has anyone has ever seen an implementation of java.nio.ByteBuffer that will grow dynamically if a putX() call overruns the capacity? The reason I want to do it this way is twofold: I don’t know how much space I need ahead of time. I’d rather not do a new ByteBuffer.allocate() then a bulk put() eve…
Java: splitting a comma-separated string but ignoring commas in quotes
I have a string vaguely like this: that I want to split by commas — but I need to ignore commas in quotes. How can I do this? Seems like a regexp approach fails; I suppose I can manually scan and enter a different mode when I see a quote, but it would be nice to use preexisting libraries. (edit:
Syntax error on token “;”, { expected after this token
why is there syntax error on this line ( shown below ) Answer You forgot the entry point method declaration. Try adding: before the line where you got the error.
Java: convert List to a join()d String
JavaScript has Array.join() Does Java have anything like this? I know I can cobble something up myself with StringBuilder: .. but there’s no point in doing this if something like it is already part of the JDK. Answer String.join With Java 8 you can do this without any third party library. If you want to…
EXT GWT + java EE
My question is: what is the best way to send my Java EE annotated entity beans’ data to the clientside to use it in a grid for example? Surely I could make the BaseModel-extended client models for each entity manually, but I wonder what could be the best-practice here. I need a step-by-step tutorial if …
Show padding zeros using DecimalFormat
I’m using DecimalFormat to format doubles to 2 decimal places like this: DecimalFormat dec = new DecimalFormat(“#.##”); double rawPercent = ( (double)(count.getCount().intValue()) / …
How to get full REST request body using Jersey?
How can one get the full HTTP REST request body for a POST request using Jersey? In our case the data will be XML. Size would vary from 1K to 1MB. The docs seem to indicate you should use MessageBodyReader but I can’t see any examples. Answer Turns out you don’t have to do much at all. See below &…