This document provides an overview of Java 8 including:
- Java 8 has approximately 9 million developers and Oracle supports versions 6-8.
- New features include default methods, lambda expressions, streams, and parallel processing capabilities.
- JavaScript integration allows JavaScript code to be run from Java, enabling database and other connections from JavaScript.
- Potential issues with Java 8 include more complex debugging due to lambda expressions and increased abstraction.
An overview of Java's history on Android and direction for the JVM on the future of Android, this talk compiles Java 8/9 APIs to Java 6, offering developers, back to Ice Cream Sandwich, more goodies to play with!
Core Java introduction | Basics | free course Kernel Training
http://kerneltraining.com/core-java/
Learn the basics of Java and gain practical experience that is required to begin your career in java programming. Kernel Training has designed classroom and online course to upgrade your knowledge and skills in core Java.
Course Curriculum:
Introduction to Java
JDK and practical applications
Java Basic Data Types and Operators
Programming Constructs, Classes and Methods, constructor and Finalizer
Polymorphism
Inheritance
Method overriding and abstract classes
Packages and Interfaces
Strings and Arrays
Enums
An overview of Java's history on Android and direction for the JVM on the future of Android, this talk compiles Java 8/9 APIs to Java 6, offering developers, back to Ice Cream Sandwich, more goodies to play with!
Core Java introduction | Basics | free course Kernel Training
http://kerneltraining.com/core-java/
Learn the basics of Java and gain practical experience that is required to begin your career in java programming. Kernel Training has designed classroom and online course to upgrade your knowledge and skills in core Java.
Course Curriculum:
Introduction to Java
JDK and practical applications
Java Basic Data Types and Operators
Programming Constructs, Classes and Methods, constructor and Finalizer
Polymorphism
Inheritance
Method overriding and abstract classes
Packages and Interfaces
Strings and Arrays
Enums
Whats New in Java 5, 6, & 7 (Webinar Presentation - June 2013)DevelopIntelligence
Kelby Zorgdrager from DevelopIntelligence explains the differences between the variations of Java and what's new in Java 7.
If you need help with Java training DevelopIntelligence and provide on-site training within two weeks. Customized and affordable for any organization.
With Java 8 released in March 2014, Oracle Java Technology Ambassador James Weaver discusses many of its new features such as lambda expressions, the stream API, and client-side capabilities with the JavaFX library.
In this workshop we would like to take a closer look at the new features of Java 7 and Java 8.
Java 7 has brought a couple of language enhancements to assist developers in their daily programming tasks and starting from Java 8 we finally have the opportunity to include a functional programming touch to Java thanks to Lambdas! Lambdas allow us to specify closures to create clean and brief solutions for which we would otherwise be obligated to write down a lot of boilerplate code.
For example in order to sort a List of Strings based on their length we can now write the following code:
Collections.sort(list, (s1, s2) -> s1.length() - s2.length());
Besides lambdas, Java 8 also comes with extension methods, allowing us to write interfaces containing implemented methods, streams and bulk data operations, granting us the opportunity to chain operations on collections to obtain a filtered or transformed set of the elements in our collection, and the possibility to pass functions as parameters. These features alone will have a major impact on the way how Java APIs can be written. There's also a brand new Date and Time API inspired on the popular JodaTime API and a couple of other language enhancements to aid Java developers in writing solutions in a more elegant way.
Be sure to follow this workshop to stay up to date with the latest evolutions of the Java programming language. Java 8 is definitely an update of the programming language which you don't want to miss out on!
Update:
Video available from Oredev: vimeo.com/53147485
Metaprogramming is the dirty little secret behind the success of many Java frameworks such as Spring and Struts2, and constitutes the backbone of many of the most fundamental APIs across the JEE technology stack. This session aims introduce the topic and highlight, with code examples, the different mechanisms and techniques to take advantage of this underused feature of the Java Programming Language.
This session will adopt a learn-by-example approach that combines the philosophy and theory behind metaprogramming with concrete code examples. The audience will be walked real-life scenarios to highlight the benefits of this technique such as minimizing the number of lines of code, reduced development time, and greater flexibility, etc… Design patterns, and best practices will be picked up along the way.
No previous knowledge or exposure to the topic is required, but an intermediate understanding of Java SE is expected.
Whats New in Java 5, 6, & 7 (Webinar Presentation - June 2013)DevelopIntelligence
Kelby Zorgdrager from DevelopIntelligence explains the differences between the variations of Java and what's new in Java 7.
If you need help with Java training DevelopIntelligence and provide on-site training within two weeks. Customized and affordable for any organization.
With Java 8 released in March 2014, Oracle Java Technology Ambassador James Weaver discusses many of its new features such as lambda expressions, the stream API, and client-side capabilities with the JavaFX library.
In this workshop we would like to take a closer look at the new features of Java 7 and Java 8.
Java 7 has brought a couple of language enhancements to assist developers in their daily programming tasks and starting from Java 8 we finally have the opportunity to include a functional programming touch to Java thanks to Lambdas! Lambdas allow us to specify closures to create clean and brief solutions for which we would otherwise be obligated to write down a lot of boilerplate code.
For example in order to sort a List of Strings based on their length we can now write the following code:
Collections.sort(list, (s1, s2) -> s1.length() - s2.length());
Besides lambdas, Java 8 also comes with extension methods, allowing us to write interfaces containing implemented methods, streams and bulk data operations, granting us the opportunity to chain operations on collections to obtain a filtered or transformed set of the elements in our collection, and the possibility to pass functions as parameters. These features alone will have a major impact on the way how Java APIs can be written. There's also a brand new Date and Time API inspired on the popular JodaTime API and a couple of other language enhancements to aid Java developers in writing solutions in a more elegant way.
Be sure to follow this workshop to stay up to date with the latest evolutions of the Java programming language. Java 8 is definitely an update of the programming language which you don't want to miss out on!
Update:
Video available from Oredev: vimeo.com/53147485
Metaprogramming is the dirty little secret behind the success of many Java frameworks such as Spring and Struts2, and constitutes the backbone of many of the most fundamental APIs across the JEE technology stack. This session aims introduce the topic and highlight, with code examples, the different mechanisms and techniques to take advantage of this underused feature of the Java Programming Language.
This session will adopt a learn-by-example approach that combines the philosophy and theory behind metaprogramming with concrete code examples. The audience will be walked real-life scenarios to highlight the benefits of this technique such as minimizing the number of lines of code, reduced development time, and greater flexibility, etc… Design patterns, and best practices will be picked up along the way.
No previous knowledge or exposure to the topic is required, but an intermediate understanding of Java SE is expected.
Sessione presentata all'Italian Agile Day 19 nov 2010
BDD Live Show
In questa sessione simuleremo una breve sessione di BDD su un problema “reale” (una semplice applicazione da riga di comando). Durante la presentazione useremo un mix di tecnologie (tra le quali Ruby e Python), ma la sessione sarà comprensibile anche a chi non conosce questi linguaggi.
Sviluppare software a colpi di test – II appuntamento: “mani in pasta col BDD.Open Campus Tiscali
Startupper, product/project manager, sviluppatori, tester, se siete rimasti impressionati dal workshop animato e irriverente sul Behavior Driven Development, non potete perdere il secondo appuntamento con Enrico Marongiu, Andrea Salidu e Alessandro Mattiello, giovedì 18 giugno dalle 18.00 alle 20.00.
La creazione di un software non è un processo semplice, vi sarà capitato di dover affrontare almeno uno di questi problemi: difficoltà di comunicazione tra il team tecnico e il cliente, definizione superficiale dei requisiti e/o delle specifiche del software, scarsa attenzione ai test, fondamentali per verificare la qualità del prodotto.
La pratica BDD (Behavior Driven Development) risolve queste difficoltà, creando un linguaggio comune comprensibile a tutti gli attori coinvolti, definendo contemporaneamente le specifiche dei requisiti e i test di accettazione/collaudo (sono gratis!!! ), e fornendo uno strumento intuitivo per monitorare l’avanzamento del progetto.
Enrico, Alessandro e Andrea vi presenteranno, attraverso 3 talk, le best practice per adottare il BDD in maniera indolore, produttiva e veloce.
Mettiamo mano al codice e realizziamo una semplice applicazione RESTful utizzando BEHAT. Sarà fornito un ambiente pronto all’uso per l’esecuzione dei test funzionali.
Portate un PC con ambiente di sviluppo e interprete php configurato e pronto all’uso (o trovate qualcuno con cui lavorare).
Chi sono Enrico, Alessandro e Andrea?
Enrico Marongiu
Enrico ha 15 anni di esperienza professionale nel mondo ICT in varie vesti e ricoprendo vari ruoli, continua a divertirsi nel creare bug di una certa entità. Al momento li crea in Tiscali divisione Media. A tempo perso insiste pervicacemente nel voler imparare a suonare il Sax.
Alessandro Mattiello
Alessandro lavora da 15 anni in Tiscali nel settore Media. Si occupa di progettazione web e negli ultimi anni ha lavorato sulla realizzazione di istella social. Si occupa di diversi progetti relativi al portale Tiscali di cui coordina le attività di sviluppo. Se avesse del tempo gli piacerebbe uscire in moto o fare fotografie, ma attualmente si diverte a fare il papà a tempo pieno.
Andrea Salidu
Andrea ha 14 anni di esperienza nello sviluppo e progettazione web application. Attualmente, lavora per Tiscali nella sezione Media e si occupa di diversi progetti web/social tra i quali istella. È molto attento alla qualità del codice e ai processi che possono essere usati per migliorarlo. A tempo perso lavora come game designer con suoi amici Fabbricastorie.
a creazione di un software non è un processo semplice, vi sarà capitato di dover affrontare almeno uno di questi problemi: difficoltà comunicazione tra il team tecnico e il cliente, definizione superficiale dei requisiti e/o delle specifiche del software, scarsa attenzione ai test, fondamentali per verificare la qualità del prodotto.
La pratica BDD (Behavior Driven Development) risolve queste difficoltà, creando un linguaggio comune comprensibile a tutti gli attori coinvolti, definendo contemporaneamente le specifiche dei requisiti e i test di accettazione/collaudo (sono gratis!!! ;-) ), e fornendo uno strumento intuitivo per monitorare l’avanzamento del progetto.
Behaviour Driven Development - Tutta questione di comunicazioneCodemotion
Codemotion Milan 2014 - Due sviluppatori che non avevano mai lavorato insieme, un side project da consegnare in tempi ragionevoli e la buzzword del momento. Abbiamo sperimentato Behaviour Driven Development sul campo e c’è piaciuto parecchio, per motivi del tutto inaspettati. Spesso il fallimento dei progetti è dato da questioni umane, di comprensione, di comunicazione, non da difficoltà tecniche. Capire cosa si deve fare e quando non è così semplice come sembra.Seguendo il BDD abbiamo migliorato la comunicazione tra di noi, aumentato la comprensione del dominio e messo a fuoco le priorità. Il talk racconta la nostra esperienza diretta.
What is Java Technology (An introduction with comparision of .net coding)Shaharyar khan
A introductory slides for those who want to learn and know some basics of Java.Also for those persons who want to compare coding difference between Java and .net
OBJECT ORIENTED PROGRAMMING LANGUAGE - SHORT NOTESsuthi
Short Notes on OOP
Object-oriented programming (OOP) is a programming paradigm based on the concept of "objects", which can contain data, in the form of fields (often known as attributes or properties), and code, in the form of procedures (often known as methods). A feature of objects is an object's procedures that can access and often modify the data fields of the object with which they are associated (objects have a notion of "this" or "self"). In OOP, computer programs are designed by making them out of objects that interact with one another. OOP languages are diverse, but the most popular ones are class-based, meaning that objects are instances of classes, which also determine their types.
Java al servizio della data science - Java developers' meetingNicola Pedot
What is Java's role in the Data Science market? Why consider solutions based on Java (and other JVM frameworks) for Data Analytics? And what solutions are available?
During this Java Developers' Meeting Datatellers will pay attention to these questions, presenting the software H2O.ai and KNIME, two Open Source platforms that in recent years are seeing a wide use especially in the analysis of big data. Attention will also be given to the synergy of the two tools, in the generation of advanced and customized Business Intelligence tools.
Seconda parte di introduzione all'ambiente di sviluppo Eclipse e Subversion con approfondimento dei plugin necessari al collegamento con un repository SVN.
May Marketo Masterclass, London MUG May 22 2024.pdfAdele Miller
Can't make Adobe Summit in Vegas? No sweat because the EMEA Marketo Engage Champions are coming to London to share their Summit sessions, insights and more!
This is a MUG with a twist you don't want to miss.
Exploring Innovations in Data Repository Solutions - Insights from the U.S. G...Globus
The U.S. Geological Survey (USGS) has made substantial investments in meeting evolving scientific, technical, and policy driven demands on storing, managing, and delivering data. As these demands continue to grow in complexity and scale, the USGS must continue to explore innovative solutions to improve its management, curation, sharing, delivering, and preservation approaches for large-scale research data. Supporting these needs, the USGS has partnered with the University of Chicago-Globus to research and develop advanced repository components and workflows leveraging its current investment in Globus. The primary outcome of this partnership includes the development of a prototype enterprise repository, driven by USGS Data Release requirements, through exploration and implementation of the entire suite of the Globus platform offerings, including Globus Flow, Globus Auth, Globus Transfer, and Globus Search. This presentation will provide insights into this research partnership, introduce the unique requirements and challenges being addressed and provide relevant project progress.
Experience our free, in-depth three-part Tendenci Platform Corporate Membership Management workshop series! In Session 1 on May 14th, 2024, we began with an Introduction and Setup, mastering the configuration of your Corporate Membership Module settings to establish membership types, applications, and more. Then, on May 16th, 2024, in Session 2, we focused on binding individual members to a Corporate Membership and Corporate Reps, teaching you how to add individual members and assign Corporate Representatives to manage dues, renewals, and associated members. Finally, on May 28th, 2024, in Session 3, we covered questions and concerns, addressing any queries or issues you may have.
For more Tendenci AMS events, check out www.tendenci.com/events
A Comprehensive Look at Generative AI in Retail App Testing.pdfkalichargn70th171
Traditional software testing methods are being challenged in retail, where customer expectations and technological advancements continually shape the landscape. Enter generative AI—a transformative subset of artificial intelligence technologies poised to revolutionize software testing.
Innovating Inference - Remote Triggering of Large Language Models on HPC Clus...Globus
Large Language Models (LLMs) are currently the center of attention in the tech world, particularly for their potential to advance research. In this presentation, we'll explore a straightforward and effective method for quickly initiating inference runs on supercomputers using the vLLM tool with Globus Compute, specifically on the Polaris system at ALCF. We'll begin by briefly discussing the popularity and applications of LLMs in various fields. Following this, we will introduce the vLLM tool, and explain how it integrates with Globus Compute to efficiently manage LLM operations on Polaris. Attendees will learn the practical aspects of setting up and remotely triggering LLMs from local machines, focusing on ease of use and efficiency. This talk is ideal for researchers and practitioners looking to leverage the power of LLMs in their work, offering a clear guide to harnessing supercomputing resources for quick and effective LLM inference.
Software Engineering, Software Consulting, Tech Lead.
Spring Boot, Spring Cloud, Spring Core, Spring JDBC, Spring Security,
Spring Transaction, Spring MVC,
Log4j, REST/SOAP WEB-SERVICES.
Prosigns: Transforming Business with Tailored Technology SolutionsProsigns
Unlocking Business Potential: Tailored Technology Solutions by Prosigns
Discover how Prosigns, a leading technology solutions provider, partners with businesses to drive innovation and success. Our presentation showcases our comprehensive range of services, including custom software development, web and mobile app development, AI & ML solutions, blockchain integration, DevOps services, and Microsoft Dynamics 365 support.
Custom Software Development: Prosigns specializes in creating bespoke software solutions that cater to your unique business needs. Our team of experts works closely with you to understand your requirements and deliver tailor-made software that enhances efficiency and drives growth.
Web and Mobile App Development: From responsive websites to intuitive mobile applications, Prosigns develops cutting-edge solutions that engage users and deliver seamless experiences across devices.
AI & ML Solutions: Harnessing the power of Artificial Intelligence and Machine Learning, Prosigns provides smart solutions that automate processes, provide valuable insights, and drive informed decision-making.
Blockchain Integration: Prosigns offers comprehensive blockchain solutions, including development, integration, and consulting services, enabling businesses to leverage blockchain technology for enhanced security, transparency, and efficiency.
DevOps Services: Prosigns' DevOps services streamline development and operations processes, ensuring faster and more reliable software delivery through automation and continuous integration.
Microsoft Dynamics 365 Support: Prosigns provides comprehensive support and maintenance services for Microsoft Dynamics 365, ensuring your system is always up-to-date, secure, and running smoothly.
Learn how our collaborative approach and dedication to excellence help businesses achieve their goals and stay ahead in today's digital landscape. From concept to deployment, Prosigns is your trusted partner for transforming ideas into reality and unlocking the full potential of your business.
Join us on a journey of innovation and growth. Let's partner for success with Prosigns.
Navigating the Metaverse: A Journey into Virtual Evolution"Donna Lenk
Join us for an exploration of the Metaverse's evolution, where innovation meets imagination. Discover new dimensions of virtual events, engage with thought-provoking discussions, and witness the transformative power of digital realms."
How to Position Your Globus Data Portal for Success Ten Good PracticesGlobus
Science gateways allow science and engineering communities to access shared data, software, computing services, and instruments. Science gateways have gained a lot of traction in the last twenty years, as evidenced by projects such as the Science Gateways Community Institute (SGCI) and the Center of Excellence on Science Gateways (SGX3) in the US, The Australian Research Data Commons (ARDC) and its platforms in Australia, and the projects around Virtual Research Environments in Europe. A few mature frameworks have evolved with their different strengths and foci and have been taken up by a larger community such as the Globus Data Portal, Hubzero, Tapis, and Galaxy. However, even when gateways are built on successful frameworks, they continue to face the challenges of ongoing maintenance costs and how to meet the ever-expanding needs of the community they serve with enhanced features. It is not uncommon that gateways with compelling use cases are nonetheless unable to get past the prototype phase and become a full production service, or if they do, they don't survive more than a couple of years. While there is no guaranteed pathway to success, it seems likely that for any gateway there is a need for a strong community and/or solid funding streams to create and sustain its success. With over twenty years of examples to draw from, this presentation goes into detail for ten factors common to successful and enduring gateways that effectively serve as best practices for any new or developing gateway.
OpenFOAM solver for Helmholtz equation, helmholtzFoam / helmholtzBubbleFoamtakuyayamamoto1800
In this slide, we show the simulation example and the way to compile this solver.
In this solver, the Helmholtz equation can be solved by helmholtzFoam. Also, the Helmholtz equation with uniformly dispersed bubbles can be simulated by helmholtzBubbleFoam.
Unleash Unlimited Potential with One-Time Purchase
BoxLang is more than just a language; it's a community. By choosing a Visionary License, you're not just investing in your success, you're actively contributing to the ongoing development and support of BoxLang.
Cyaniclab : Software Development Agency Portfolio.pdfCyanic lab
CyanicLab, an offshore custom software development company based in Sweden,India, Finland, is your go-to partner for startup development and innovative web design solutions. Our expert team specializes in crafting cutting-edge software tailored to meet the unique needs of startups and established enterprises alike. From conceptualization to execution, we offer comprehensive services including web and mobile app development, UI/UX design, and ongoing software maintenance. Ready to elevate your business? Contact CyanicLab today and let us propel your vision to success with our top-notch IT solutions.
top nidhi software solution freedownloadvrstrong314
This presentation emphasizes the importance of data security and legal compliance for Nidhi companies in India. It highlights how online Nidhi software solutions, like Vector Nidhi Software, offer advanced features tailored to these needs. Key aspects include encryption, access controls, and audit trails to ensure data security. The software complies with regulatory guidelines from the MCA and RBI and adheres to Nidhi Rules, 2014. With customizable, user-friendly interfaces and real-time features, these Nidhi software solutions enhance efficiency, support growth, and provide exceptional member services. The presentation concludes with contact information for further inquiries.
In software engineering, the right architecture is essential for robust, scalable platforms. Wix has undergone a pivotal shift from event sourcing to a CRUD-based model for its microservices. This talk will chart the course of this pivotal journey.
Event sourcing, which records state changes as immutable events, provided robust auditing and "time travel" debugging for Wix Stores' microservices. Despite its benefits, the complexity it introduced in state management slowed development. Wix responded by adopting a simpler, unified CRUD model. This talk will explore the challenges of event sourcing and the advantages of Wix's new "CRUD on steroids" approach, which streamlines API integration and domain event management while preserving data integrity and system resilience.
Participants will gain valuable insights into Wix's strategies for ensuring atomicity in database updates and event production, as well as caching, materialization, and performance optimization techniques within a distributed system.
Join us to discover how Wix has mastered the art of balancing simplicity and extensibility, and learn how the re-adoption of the modest CRUD has turbocharged their development velocity, resilience, and scalability in a high-growth environment.
AI Pilot Review: The World’s First Virtual Assistant Marketing SuiteGoogle
AI Pilot Review: The World’s First Virtual Assistant Marketing Suite
👉👉 Click Here To Get More Info 👇👇
https://sumonreview.com/ai-pilot-review/
AI Pilot Review: Key Features
✅Deploy AI expert bots in Any Niche With Just A Click
✅With one keyword, generate complete funnels, websites, landing pages, and more.
✅More than 85 AI features are included in the AI pilot.
✅No setup or configuration; use your voice (like Siri) to do whatever you want.
✅You Can Use AI Pilot To Create your version of AI Pilot And Charge People For It…
✅ZERO Manual Work With AI Pilot. Never write, Design, Or Code Again.
✅ZERO Limits On Features Or Usages
✅Use Our AI-powered Traffic To Get Hundreds Of Customers
✅No Complicated Setup: Get Up And Running In 2 Minutes
✅99.99% Up-Time Guaranteed
✅30 Days Money-Back Guarantee
✅ZERO Upfront Cost
See My Other Reviews Article:
(1) TubeTrivia AI Review: https://sumonreview.com/tubetrivia-ai-review
(2) SocioWave Review: https://sumonreview.com/sociowave-review
(3) AI Partner & Profit Review: https://sumonreview.com/ai-partner-profit-review
(4) AI Ebook Suite Review: https://sumonreview.com/ai-ebook-suite-review
AI Pilot Review: The World’s First Virtual Assistant Marketing Suite
Java 8 Overview
1. Java 8
Good & Bad
Overview by Nicola Pedot - 26 giugno 2014
https://creativecommons.org/licenses/by/3.0/it
2. Status
On 2014, Java is one of the most used programming
language for client-server applications, with approximately
9 million developers.
Oracle Java Versions:
6 archived
7 production ready (java.net)
8 for developers (java.com)
4. Java 8 Parts
Process
Development Kit- JDK
Virtual Machine VM
Language
Runtime Libraries - JRE
Editions - JEE, JSE, JME, JEmbedded
5. Java Community Process
The JCP remains the governing body for all standard Java
SE APIs and related interfaces. If a proposal accepted into
this process intends to revise existing standard interfaces,
or to define new ones, then a parallel effort to design,
review, and approve those changes must be undertaken in
the JCP, either as part of a Maintenance Review of an
existing JSR or in the context of a new JSR.
6. JDK Enhancement-Proposal
JEP 1: JDK Enhancement-Proposal & Roadmap Process
Author Mark Reinhold
Organization Oracle
Created 2011/6/23
Updated 2012/12/4
The primary goal of this process is to produce a regularly-updated list of
proposals to serve as the long-term Roadmap for JDK Release Projects and related
efforts.
This process is open to every OpenJDK Committer.
This process does not in any way supplant the Java Community Process.
7. Java JDK - OpenJDK
JDK 8 was the second part of "Plan B". The single driving
feature of the release was Project Lambda. (Project Jigsaw
was initially proposed for this release but later dropped).
Additional features proposed via the JEP Process were
included so long as they fit into the overall schedule
required for Lambda. Detailed information on the features
included in the release can be found on the features page.
The source is open and avaliable on Mercurial
repository.
8. Java VM - HotSpot
Below you will find the source code for the Java HotSpot virtual
machine, the best Java virtual machine on the planet.
The HotSpot code base has been worked on by dozens of people,
over the course of 10 years, so far. (That's good and bad.) It's
big. There are nearly 1500 C/C++ header and source files,
comprising almost 250,000 lines of code. In addition to the
expected class loader, bytecode interpreter, and supporting
runtime routines, you get two runtime compilers from bytecode to
native instructions, 3 (or so) garbage collectors, and a set of
high-performance runtime libraries for synchronization, etc.
9. Java 8 Hot Topics
Default Methods
Function Iterfaces (Closure, Lambda) or AntiScala
Streams
Parallel
Javascript Nashorn
Java Time
SNI IPV6
Security
10. Default methods
Default methods enable you to add new
functionality to the interfaces of your libraries
and ensure binary compatibility with code
written for older versions of those interfaces.
Note: interfaces do not have any state
11. Default method syntax
public interface oldInterface {
public void existingMethod();
default public void newDefaultMethod() {
System.out.println("New default method"
" is added in interface");
}
}
The following class will compile successfully in Java JDK 8,?
public class oldInterfaceImpl implements oldInterface {
public void existingMethod() {
// existing implementation is here…
}
}
If you create an instance of oldInterfaceImpl:?
oldInterfaceImpl obj = new oldInterfaceImpl ();
// print “New default method add in interface”
obj.newDefaultMethod();
12. Default method conflict
java: class Impl inherits unrelated defaults for defaultMethod() from types InterfaceA and InterfaceB
In order to fix this class, we need to provide default method implementation:
public class Impl implements InterfaceA, InterfaceB {
public void defaultMethod(){
// existing code here..
InterfaceA.super.defaultMethod();
}
}
13. Default method good
The great thing about using interfaces instead
of adapter classes is the ability to extend
another class than the particular adapter.
Simil multiple inheritance.
Finally, library developers are able to evolve
established APIs without introducing
incompatibilities to their user's code.
14. Default method bad
In a nutshell, make sure to never override a default
method in another interface. Neither with another
default method, nor with an abstract method.
Before Java 7, you would only need to look for the
actually invoked code by traversing down a linear
class hierarchy. Only add this complexity when you
really feel it is absolutely necessary.
15. Lambda: functional interface
A functional interface is any interface that
contains only one abstract method. (A
functional interface may contain one or more
default methods or static methods.)
16. Lambda syntax
//Prima:
List list1 = Arrays.asList(1,2,3,5);
for(Integer n: list1) {
System.out.println(n);
}
//Dopo:
List list2 = Arrays.asList(1,2,3,5);
list2.forEach(n -> System.out.println(n));// default method forEach
//Espressioni lambda e doppio due punti static method reference
list2.forEach(System.out::println);
20. Stream Bad Parts
“Java 8 Streams API will be the single biggest source of
new Stack Overflow questions.”
With streams and functional thinking, we’ll run into a
massive amount of new, subtle bugs. Few of these bugs
can be prevented, except through practice and staying
focused. You have to think about how to order your
operations. You have to think about whether your streams
may be infinite. [14]
21. Stream Bad Parts (2)
“If evaluation of one parallel stream results in a very long running
task, this may be split into as many long running sub-tasks that
will be distributed to each thread in the pool. From there, no
other parallel stream can be processed because all threads will
be occupied.”
If a program is to be run inside a container, one must be very
careful when using parallel streams. Never use the default pool
in such a situation unless you know for sure that the container
can handle it. In a Java EE container, do not use parallel
streams. [15]
22. Parallel Lang Tools: StampedLock
The ReentrantReadWriteLock had a lot of shortcomings: It
suffered from starvation. You could not upgrade a read lock
into a write lock. There was no support for optimistic reads.
Programmers "in the know" mostly avoided using them.
StampedLock addresses all these shortcomings
23. Parallel Lang Tools:Concurrent Adders
Concurrent Adders:
this is a new set of classes for managing counters written
and read by multiple threads. The new API promises
significant performance gains, while still keeping things
simple and straightforward.
24. Bad Part
We’re paying the price for shorter, more
concise code with more complex debugging,
and longer synthetic call stacks.
25. The Reason
The reason is that while javac has been
extended to support Lambda functions, the
JVM still remains oblivious to them.
30. JavaScript with stream
DSL.using(conn)
.select(...) // this is folded code.
// This fetches a List<Map<String, Object>> as
// your ResultSet representation
.fetchMaps()
// This is Java 8's standard Collection.stream()
.stream()
// And now, r is like any other JavaScript object
// or record!
.forEach(function (r) {
print(r.TABLE_SCHEMA + '.'
+ r.TABLE_NAME + ' has '
+ r.CNT + ' columns.');
});
31. Javascript Problem
In this case the bytecode code is dynamically
generated at runtime using a nested tree of
Lambda expressions. There is very little
correlation between our source code, and the
resulting bytecode executed by the JVM. The
call stack is now two orders of magnitude
longer.
32. The Hard Side
Haskell is good at preventing bugs.
Java without lambda has readable stacktrace.
In Groovy is harder reading exceptions,
Java8 Lambda is also harder,
Javascript is even harder.
33. JavaTime, JodaTime’s revenge
● The Calendar class was not type safe.
● Because the classes were mutable, they could not be
used in multithreaded applications.
● Bugs in application code were common due to the
unusual numbering of months and the lack of type
safety.
34. JodaTime syntax
import java.time.Instant;
Instant timestamp = Instant.now();
This class format follows the ISO-8601
2013-05-30T23:38:23.085Z
Come gestire le vecchie date?
Date.toInstant()
public static Date from(Instant instant)
Calendar.toInstant()
Other classes Clock, Period,...
35. SNI IPV6
Assigning a separate IP address for each site increases the cost of hosting since requests for IP addresses must be justified to the
regional internet registry and IPv4 addresses are now in short supply.
An extension to TLS called Server Name Indication (SNI) addresses this issue by sending the name of the virtual domain as part
of the TLS negotiation. <<Wikipedia>>
E’ possibile configurare in un webserver più
virtual host con diversi certificati SSL
utilizzando un solo indirizzo IP.
provocazione...in vista dell’esaurimento di IP di
InternetOfThings…. Java Everywhere?
37. Others...
1. Process termination
Process destroyForcibly(); isAlive(); waitFor(long timeout, TimeUnit unit);
2. Optional Values
String name = computer.flatMap(Computer::getSoundcard)
.flatMap(Soundcard::getUSB)
.map(USB::getVersion)
.orElse("UNKNOWN");
3. Annotate Anything
Type Annotations are annotations that can be placed anywhere you use a type. This includes the new operator, type casts,
implements clauses and throws clauses
39. New Domains
Java started simple by design, now it has to
gain complexity to model new domains.
from Static Object Orienteed to
->(functional) Parallel Event Orienteed
->(dynamic) Syntax & Check relaxed
== More fun & more dangerous times ahead!
40. from Java8 to Java9
from….
Enterprise Edition
Standard Edition
Embedded Edition
Mobile Edition
…. to Java9 complete module system
41. Compact Profiles
Java Compact Profiles,
A reasonably configured Java SE-Embedded 8 for ARMv5/Linux
compact1 profile comes in at less than 14MB
compact2 is about 18MB and
compact3 is in the neighborhood of 21MB.
For reference, the Java SE-Embedded 7u21 Linux environment requires 45MB.