Java Reflection in Action (In Action series)

Rating:
Summary: If only it could do everything marketing promised.
Review: I spend most of my life re-doing old code that for some reason needs to be expanded, changed, fixed or whatever. The old story about writing the program is only 10% of the effort, (really it may be 2%) is true. If you could double the time spent writing the program itself it would be well worth it (if the world would let you). Wouldn't it be nice to have programs that - without work on your part - could exmanine itself and then change to do something else depending on what it finds.

Reflection won't take twice as long to code. But it will a bit take longer in the design phase. Nor can reflection promise to do everything that the salesmen can promise to the new prospects, nothing can do that.

Reflection is a technique that can be of great value in some instances, it's ceratinly something you need to have in your mental toolbox.

This book is by one of the pioneers in reflection, and his son who uses reflection to solve day-to-day problems.

Rating:
Summary: A practical "how to" manual for applying reflection
Review: Java Reflection In Action by the collaborative team of Ira and Nate Forman is a practical "how to" manual for applying reflection to computer programming. Reflection is the ability of a running program to look at itself and its environment, and change what it does according to what it sees. It is an inbuilt feature of the Java language and allows one to sidestep a common source of maintenance woes. Java Reflection In Action walks the programmer through a complete understanding of reflection and some of the most useful reflective solutions to replace "hard-coded" ones. An excellent self-teaching resource for intermediate to advanced students and practitioners of Java programming, Java Reflection In Action is packed from cover to cover with examples, flowcharts, sample code, and more, all effectively designed to facilitate instruction.


Rating:
Summary: Outstanding guide to reflection
Review: There are only a handful of books that every Java programmer should own. This book manages to enter into that elite group of books by providing exceptional coverage of an area of Java programming that is generally poorly covered and often misunderstood. Reflection is a topic that many programmers know about but don't truly understand. Reflection can provide simple ways to get out of complex problems, which makes it well worth knowing. Reflection is one of those tools that you never knew you needed until you learn it.

The authors of this book are a father/son team that have been working with reflection for years. They attack reflection in small pieces, making each topic crystal clear before moving on to the next. In keeping with the "action" from the title, the authors show examples of each aspect of reflection, breaking down each line of code with complete explanations.

The book starts with the basics of reflection, looking at how to examine a class at runtime and dynamically load it. The book then moves on to demonstrating how to use the Proxy class. Later chapters show how to examine the call stack, customize class loaders, and transform one class into another. Performance is covered with a chapter that gives some good examples of benchmarking the cost of using reflection. The book ends with a look at the impact of Java 1.5 on reflection.

The best advice I can give is, buy this book. You will be amazed at the things that you didn't know you could do with Java.

Rating:
Summary: Well organized, and written introduction to reflection
Review: This is a well thought out introduction to reflection in Java. It steps through the API from dynamic object creation, through type, method and field inspection. The code examples are a little long but they are well annotated. The illustrations are minimal, but used well.

I would have liked more on how to use reflection to build extension mechanisms. And the section on code generation wasn't particularly good.

Worthwhile if you are going to be doing a lot of reflection work and you want an introduction to the API. There isn't much in the way of reference, and information on how reflection works in other languages is minimal.