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Tag: java

What is this: [Ljava.lang.Object;?

I get this when I call toString on an object I received from a function call. I know the type of the object is encoded in this string, but I don’t know how to read it. What is this type of encoding called? Answer [Ljava.lang.Object; is the name for Object[].class, the java.lang.Class representing the cl…

How to make a copy of ArrayList object which is type of List?

I studied that Java passes object references by value, and in order to make a local copy of an object I can either do clone() or copy-constructor. I also looked at deep/shallow copy as well as several posts on Stack Overflow. I am looking at this example: Only a few articles I read mention that ArrayList impl…

dynamically increasing java heap space

I have written a java program that tests the speed of a couple of multi-threading algorithms on different machines with various numbers of processors. On some machines, merge sort* fails because it requires a sizable heap space to work on very large arrays. I can easily change the java heap space myself befor…

Holidays – is there a java implementation?

I’d like to know if there is a jar-file out there that could do the following: If there isn’t, why? Surely there are lots of properly based rules for the holidays in 99% of the times. Right now we’re mainting a table in our database, with the countries + we have some implementation when it c…

Why use finally

I never properly understood the use of the finally statement. Can anyone tell me what the difference is between: on the one hand and: On the other Answer They differ if the try-block completes by throwing a java.lang.Throwable that is not a java.lang.Exception, for instance because it is a java.lang.Error suc…