Core Java Technology Section Index | Page 4

Apart from the accept all filter, until Java 6, there were no predefined filters. Java 6 introduces the FileNameExtensionFilter, allowing you to define one or more types of files for the user to s...more

Pre-Java 6, you had to either use native code or fork off a platform specific command in a sub-process. With Java 6, there is a setWritable() method.

Use this annotation to tell the compiler that the method is supposed to be overriding a method in the superclass. If by chance it doesn't, the compiler tells you. This allows you to catch typos li...more

The Console class has methods to read console input with readLine() and readPassword(). These methods throw IOError instead of IOException. My best guess at why the difference is becasue IOError i...more

What are the differences between instance methods and class methods?

How do you use the ternary operator?

It means that the JVM has run out of all the memory that has been allocated to it. You can change the amount of memory allocated for use by your JVM using the -Xms and -Xmx command line parameter...more

I have an interface that is implemented by 100 classes, if I add a method to the interface will my classes compile? How can I fix any errors?

It is true that Java does not allow operator overloading. It is also true that an exception was made for String, although this is out of the control of developers as it is a built in feature of J...more

ResourceBundle is a property file handler with locales support, it allows you to support multiple languages in your application. There's a full explaination on what ResourceBundle is and how it h...more

Nested switch statements are allowed. Just make sure you remember to have all the break statements in the correct places. E.g: int i; int j; switch(i){     case 0: System.out....more

It is not possible to obtain this information on *nix machines since this information is not stored about the files, only file modification date is stored. Therefore java has no methods for obtai...more

Yes. If the objects are only reachable from themselves and nowhere else, they are a candidate for garbage collection.

By default, cloning yields a shallow copy. By shallow, we mean the object is copied, but the contained objects are not. What a deep copy does it copy the cloned object, as well as all the objects...more

Basically nothing. It is just semantics. A method's arity is the number of arguments it takes. The arity of the main() method of a class is one since it takes one argument, a String[].more