Tom Deneau

This article looks at a Java Virtual Machine (JVM) feature called Escape Analysis in some detail and how the JVM can use it to improve an application's performance. As you'll see, understanding what the JVM can do with escape analysis can help explain some otherwise non-intuitive performance results. A Performance Puzzle Let's assume you have a utility class that generates values by keeping some internal state of the last value generated and using it to arrive at the next value. Since the class maintains some internal state, and since this is a utility class that you might use in multithreaded environments, you decide to synchronize the getNext() method. You might code it as: public class Generator { private int lastgen;  // saved state Generator(int value) { // initialize lastgen using supplied value   } public synchronized int getNext() { int nextgen = somefunction(la... (more)