This book constitutes the refereed proceedings of the 20th European Conference on Object-Oriented Programming, ECOOP 2006, held in Nantes, France in July 2006. 20 revised full papers, together with 3 keynote papers were carefully reviewed and selected. The papers are organized in topical sections on program query and persistence, ownership and concurrency, languages, type theory, types for object-oriented languages, tools, and modularity. 5 more papers celebrate the 20th anniversary of ECOOP.

The21stEuropeanConferenceonObject-OrientedProgramming,ECOOP2007, was held in Berlin, Germany, on July 30 to August 3, 2007. ECOOP is the most importantand inspiring forumin Europeandbeyond for researchers,practiti- ers, and students working in that smorgasbord of topics and approaches known as object orientation. This topic area was explored and challenged by excellent invited speakers—two of which were the winners of this year’s Dahl-Nygaard award—in the carefully refereed and selected technical papers, on posters, via demonstrations, and in tutorials. Each of the many workshops complemented this with a very interactive and dynamic treatment of more speci?c topics. - nally, panels allowed for loud and lively disagreement. Yet, it is one of ECOOP’s specialqualities that this plethora ofactivities add upto a coherentandexciting whole, rather than deteriorating into chaos. The Program Committee received 161 submissions this year. Only 135 of them were carried through the full review process, because of a number of - tractions and a number of submissions of abstracts that were never followed by a full paper. However, the remaining papers were of very high quality and we accepted25 of them for publication. Helping very goodpapers to be published is more useful than having an impressively low acceptance rate. The papers were selected according to four groups of criteria, whose priority depended on the paper: relevance; originality and signi?cance; precisionand correctness;and p- sentation and clarity. Each paper had three, four, or ?ve reviews, depending on how controversial it was.

This book contains the final reports of 19 workshops held during the 20th European Conference on Object-Oriented Programming, ECOOP 2006, held in Nantes, France in July 2006. The 19 reports cover the entire range of object technology and related topics, presenting a coherent and highly representative snapshot of the major trends in the field.

It is a pleasure to present the proceedings of the 22nd European Conference on Object-Oriented Programming (ECOOP 2008) held in Paphos, Cyprus. The conference continues to serve a broad object-oriented community with a tech- cal program spanning theory and practice and a healthy mix of industrial and academic participants. This year a strong workshop and tutorial program c- plementedthemaintechnicaltrack.Wehad13workshopsand8tutorials,aswell as the co-located Dynamic Language Symposium (DLS). Finally, the program was rounded out with a keynote by Rachid Guerraoui and a banquet speech by James Noble. As in previous years, two Dahl-Nygaard awards were selected by AITO, and for the ?rst time, the ECOOP Program Committee gave a best paper award. Theproceedingsinclude27papersselectedfrom138submissions.Thepapers werereviewed in a single-blind process with three to ?ve reviews per paper. P- liminaryversionsofthereviewsweremadeavailabletotheauthorsaweekbefore the PC meeting to allow for short (500 words or less) author responses. The - sponses were discussed at the PC meeting and were instrumental in reaching decisions. The PC discussions followed Oscar Nierstrasz’Champion pattern. PC papers had ?ve reviews and were held at a higher standard.

Welcome to the proceedings of ECOOP 2009! Thanks to the local organizersfor working hard on arranging the conference — with the hard work they put in, it was a great success. Thanks to Sophia Drossopoulou for her dedicated work as PC Chair in assembling a ?ne scienti?c program including forward-looking keynotes, and for her e?orts to reduce the environmental impact of the PC meeting by replacing a physical meeting with a virtual meeting. I would also like to thank James Noble for taking the time and e?ort to write up last year’s banquet speech so that it could be included in this year’s proceedings. One of the strong features of ECOOPis the two days of workshopspreceding themainconferencethatallowsintenseinteractionbetweenparticipants.Thanks to all workshop organizers. Lastyear’ssuccessfulsummerschooltutorialswerefollowedupthisyearwith seven interesting tutorials. Thanks to the organizers and speakers. This year’s Dahl-Nygaard award honored yet another pioneer in the ?eld, namely, David Ungar for his contributions includingSelf. I appreciate his e?orts in providing us with an excellent award talk. The world is changing and so is ECOOP. Please contemplate my short note on the following pages entitled On Future Trends for ECOOP.

This book constitutes the refereed proceedings of the 24th European Conference on Object-Oriented Programming, ECOOP 2010, held in Maribor, Slovenia, in June 2010. The 24 revised full papers, presented together with one extended abstract were carefully reviewed and selected from a total of 108 submissions. The papers cover topics such as programming environments and tools, theoretical foundations of programming languages, formal methods, concurrency models in Java, empirical methods, type systems, language design and implementation, concurrency abstractions and experiences.

This book constitutes the refereed proceedings of the 26th European Conference on Object-Oriented Programming, ECOOP 2012, held in Beijing, China, in June 2012. The 27 revised full papers presented together with two keynote lectures were carefully reviewed and selected from a total of 140 submissions. The papers are organized in topical sections on extensibility, language evaluation, ownership and initialisation, language features, special-purpose analyses, javascript, hardcore theory, modularity, updates and interference, general-purpose analyses.