A long time ago in a galaxy far, far away... Java open source developers managed to the see the previously secret plans to the Empire's ultimate weapon, the JAVA™ COLLECTIONS FRAMEWORK. Evading the dreaded Imperial Starfleet, a group of freedom fighters investigate common developer errors and bugs to help protect their vital software. In addition, they investigate the performance of the Empire’s most popular weapon: HashMap. With this new found knowledge they strike back! Pursued by the Empire's sinister agents, JDuchess races home aboard her JVM, investigating proposed future changes to the Java Collections and other options such as Immutable Persistent Collections which could save her people and restore freedom to the galaxy.... Raoul-Gabriel Urma is a PhD in Computer Science at the University of Cambridge. His research centers on programming languages and software engineering. He is an author of the upcoming book Java 8 in Action: Lambdas, Streams, and functional-style programming published by Manning. In addition, Raoul has written over 10 peer-reviewed articles and given over 20 technical talks at international conferences. He has worked for large companies such as Google, eBay, Oracle, and Goldman Sachs, as well as for several startup projects. Richard Warburton is an empirical technologist and solver of deep-dive technical problems. Recently he has written a book on Java 8 Lambdas for O’Reilly. He’s worked as a developer in many areas including Statistical Analytics, Static Analysis, Compilers and Network Protocols. He is a leader in the London Java Community and runs Openjdk Hackdays. Richard is also a known conference speaker, having talked at JavaOne, Devoxx, JFokus, Devoxx UK, Geecon, JAX London and Codemotion. He has obtained a PhD in Computer Science from The University of Warwick.