Chapter 1. Antroduction to Java - Core Java
1. T he authors of Java have published a shorter summary that is organized along the following 11 buzzwords:
Simple Portable, Object Oriented, Interpreted, Network-Savvy, High Performance, Robust, Multithreaded, Secure, Dynamic, Architecture Neutral .
2. The just-in-time compilers have become so good that they are competitive with traditional compilers and, in some cases, even outperform them because they have more information available. For example, a just-in-time compiler can monitor which code is executed frequently and optimize just that code for speed. A more sophisticated optimization is the elimination (or “ inlining ” ) of function calls. The just-in-time compiler knows which classes have been loaded. It can use inlining when, based upon the currently loaded collection of classes, a particular function is never overridden, and it can undo that optimization later if necessary.
3. On the downside, thread implementations on the major platforms differ widely, and Java makes no effort to be platform independent in this regard. Only the code for calling multithreading remains the same across machines; Java offloads the implementation of multithreading to the underlying operating system or a thread library.