Solve reallife programming problems with a fraction of the code that pure objectoriented programming requires. Use Scala and Clojure to solve indepth problems with two sets of patterns objectoriented patterns that become more concise with functional programming and natively functional patterns. Your code will be more declarative with fewer bugs and lower maintenance costs. Functional languages have their own patterns that enable you to solve problems with less code than objectoriented programming alone. This book introduces you the experienced Java programmer to Scala and Clojure practical productionquality languages that run on the JVM and interoperate with existing Java. By using both the statically typed typeinferred Scala and the dynamically typed modern Lisp Clojure youll gain a broad understanding of functional programming. For each pattern youll first see the traditional objectoriented solution and then dig into the functional replacements in both Scala and Clojure. These patterns are common in the functional world and deserve to become part of your problemsolving toolkit. On the objectoriented side youll see many common patterns such as Command Strategy and Null Object. On the functional side youll learn core functional patterns such as Memoization Lazy Sequence and Tail Recursion. Each pattern helps you solve a common programming problem. Working through them gives you a set of patterns you can use to solve problems you come across while writing programs. Finally youll learn how to work your existing Java code into new Scala or Clojure projects. You can start off small adding functional code little by little so you can complement your existing knowledge with Scala and Clojure as these languages gain popularity on the JVM. What You Need Clojure 1.5 and Scala 2.10. Optionally Eclipse with plugins.