There are 3 permutations of a try…catch…finally block in java. try…catch try…catch…finally try…finally Once the finally block is executed, control goes to the next line after the finally …
How to calculate “time ago” in Java?
In Ruby on Rails, there is a feature that allows you to take any Date and print out how “long ago” it was. For example: Is there an easy way to do this in Java? Answer Take a look at the PrettyTime library. It’s quite simple to use: You can also pass in a locale for internationalized message…
Why does a BufferedImage require so much memory beyond the size of its data array?
I’m trying to determine how much heap any given TYPE_INT_ARGB BufferedImage will use so that, for a program which is doing some image processing, I can set a reasonable max heap based on the size of image we feed it. I wrote the following program as a test, which I then used to determine the least maxim…
Recognise an arbitrary date string [closed]
Closed. This question does not meet Stack Overflow guidelines. It is not currently accepting answers. We don’t allow questions seeking recommendations for books, tools, software libraries, and more. You can edit the question so it can be answered with facts and citations. Closed 1 year ago. Improve this quest…
Java generics super keyword
I went through these topics Generics..? Super T Bounding generics with ‘super’ keyword However, I still seem to be kind of lost with super keyword: When we declare a collection like that: shouldn’t it be the opposite – we have a list that contains some objects (of unknown type) which a…
How can I make Java print quotes, like “Hello”?
How can I make Java print “Hello”? When I type System.out.print(“Hello”); the output will be Hello. What I am looking for is “Hello” with the quotes(“”). Answer The double quote character has to be escaped with a backslash in a Java string literal. Other charact…
How to change root logging level programmatically for logback
I have the following logback.xml file: Now, upon the occurrence of a specific event, I want to programmatically change the level of the root logger from debug to error. I can’t use variable substitution, it is mandatory that I do this within the code. How can it be done ? Thanks. Answer Try this: Note t…
How to get the formatted value of a number for a cell in Apache POI?
I wanted to get the value of a Numeric cell as a simple string. Suppose there the type of cell is numeric with value 90%. Now I cannot use cell.getStringCellValue() as it will throw exception. I also …
How to specify SQL comments through JPA annotations?
Is there any way to specify SQL comments through JPA annotations? Comments for tables and columns. Answer Is there any way to specify SQL comments through JPA annotations? Comments for tables and columns. No. If you want to define tables and columns comments, your best option is to do it after the facts in th…
Convert boolean to int in Java
What is the most accepted way to convert a boolean to an int in Java? Answer ^^ PS : true = 1 and false = 0