I have a class with a private static final field that, unfortunately, I need to change it at run-time. Using reflection I get this error: java.lang.IllegalAccessException: Can not set static final boolean field Is there any way to change the value? Field hack = WarpTransform2D.class.getDeclaredField(“USE_HACK”); hack.setAccessible(true); hack.set(null, true); 14 s 14 Assuming no SecurityManager is … Read more
In Java we use final keyword with variables to specify its values are not to be changed. But I see that you can change the value in the constructor / methods of the class. Again, if the variable is static then it is a compilation error. Here is the code: import java.util.ArrayList; import java.util.List; class … Read more
I am reading a book about Java and it says that you can declare the whole class as final. I cannot think of anything where I’d use this. I am just new to programming and I am wondering if programmers actually use this on their programs. If they do, when do they use it so … Read more
Every time I go from heavy C++ coding to Java, it takes me a little while to adapt to the lack of const-correctness in Java. This usage of const in C++ is much different than just declaring constant variables, if you didn’t know. Essentially, it ensures that an object is immutable when accessed through a special kind of pointer … Read more
You keep updating both high and low inside the run() method, making them by definition not effectively final. Since you don’t need them outside the run() method anyway, just move the two lines inside. public void HiLo(int[] numbers){ Runnable r2 = new Runnable(){ @Override public void run() { int high = numbers[0]; int low = … Read more
Replace case MorrisBoard.RING.OUT: with So this will really be a constant as in “determined at compilation”. The specification precises that a “SwitchLabel” must be case followed by a constant expression case followed by the name of an enum value or default What is considered a valid constant expression is described here in the specification. It’s fairly limited.
