Jun 8, 2009 · Optional makes a method contract explicit for a caller, however, one may find such signature too verbose. Update: Java 8 includes the class java.util.Optional out-of-the-box, so there is no need to use guava for this particular reason in Java 8. The method name is a bit different though. Builder pattern

May 28, 2012 · I am writing a method that should accept as its parameter an object of one of two types which do not share a parent type other than Object. For example, the types are Dreams and Garlic. You can do both dreams.crush() and garlic.crush(). I want to have a method utterlyDestroy(parameter), that would accept as its parameter both Dreams and Garlic.

Dec 4, 2009 · Java also provides a nice way of calling async methods. in java.util.concurrent we have ExecutorService that helps in doing the same. Initialize your object like this - private ExecutorService asyncExecutor = Executors.newFixedThreadPool(Runtime.getRuntime().availableProcessors()); and then call …

Jan 11, 2010 · It is not possible to call non-static method within static method. The logic behind it is we do not create an object to instantiate static method, but we must create an object to instantiate non-static method. So non-static method will not get object for its instantiation inside static method, thus making it incapable for being instantiated.

Make the variable a member variable (field) of the Activity or other subclass of Context by removing the static modifier and placing it within the class body; Keep it static and delay the initialization to a later point (e.g. in the onCreate method); Make it …

No. Java methods can only return one result (void, a primitive, or an object), and creating a struct-type class like this is exactly how you do it. As a note, it is frequently possible to make classes like your ReturningValues immutable like this:

The common way is to make the private method protected or package-private and to put the unit test for this method in the same package as the class under test. Guava has a @VisibleForTesting annotation, but it's only for documentation purposes.

I'm a bit new to java and i recently learned about methods(so cool!). I want to know if its possible to declare a variable in my main method and use it in my other methods. What i am trying to do is

Then, to call on the method, type pause(ms) but replace ms with the number of milliseconds to pause. That way, you don't have to insert the entire try-catch statement whenever you want to pause. That way, you don't have to insert the entire try-catch statement whenever you want to …

Since you want to call a non-static method from main, you just need to create an object of that class consisting non-static method and then you will be able to call the method using objectname.methodname(); But if you write the method as static then you won't need to create object and you will be able to call the method using methodname(); from ...