A very useful and free JVM profiler is VisualVM. At the time of writing this book, this tool normally comes bundled when you download and install the Java Development Kit (JDK) from the Oracle Java site (http://www.oracle.com/technetwork/java/javase). In this distribution, the tool is located in $JAVA_HOME/bin and named jvisualvm.sh (for UNIX-based environments) or jvisualvm.bat (for Windows).

As an alternative, you can download it from its own site (http://visualvm.java.net). This is where you'll find the unbranded bleeding-edge version.

The core of VisualVM is shared by the NetBeans IDE (https://netbeans.org). So, if you use the NetBeans profiler, you'll be using a lot of the functionality that is the same as those found in VisualVM, but with differentiating workflows. There's also a launcher plugin of VisualVM for the Eclipse IDE (http://eclipse.org) available at https://visualvm.java.net/eclipse-launcher.html.

All examples in this book are based on the current version, VisualVM...