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Java is Pass-by-Value, Dammit! - Scott Stanchfield. Introduction I finally decided to write up a little something about Java's parameter passing. I'm really tired of hearing folks (incorrectly) state "primitives are passed by value, objects are passed by reference". I'm a compiler guy at heart. The terms "pass-by-value" semantics and "pass-by-reference" semantics have very precise definitions, and they're often horribly abused when folks talk about Java. Pass-by-value The actual parameter (or argument expression) is fully evaluated and the resulting value is copied into a location being used to hold the formal parameter's value during method/function execution. Pass-by-reference The formal parameter merely acts as an alias for the actual parameter.

Java is strictly pass-by-value, exactly as in C. When the method or constructor is invoked (15.12), the values of the actual argument expressions initialize newly created parameter variables, each of the declared Type, before execution of the body of the method or constructor. The Litmus Test. Xah's Java Tutorial. This is a example-based tutorial on Java the language. This tutorial does not use jargons and metaphors nor discuss software engineering methodologies (⁖ programing patterns). This tutorial also avoids computer science perspective ⁖ {memory allocation, garbage collection, stacks, pointers/references}. If you are a programer familiar with a high-level languages such as {Visual Basic, PHP, JavaScript, Python}, you'll find this tutorial clear and easy to understand. The code here are tested with Java 1.5.0. For latest news and additions, subscribe: Xah Programing Blog. … what society overwhelmingly asks for is snake oil.

Spend 30 minutes on each item per day, in order. First, read this: What are OOP's Jargons & Complexities? Basic Syntax & Types Intro to Java References Class & Inheritance Abstract class, Interface, Packages Misc Functional Programing Exercise Download the whole thing for $5. About The Author. Note: Java is a trademark of Sun Microsystems Inc. The Java™ Tutorials. The Java Tutorials are practical guides for programmers who want to use the Java programming language to create applications. They include hundreds of complete, working examples, and dozens of lessons. Groups of related lessons are organized into "trails". The Java Tutorials primarily describe features in Java SE 8.

For best results, download JDK 8. What's New The Java Tutorials are continuously updated to keep up with changes to the Java Platform and to incorporate feedback from our readers. Lambda expressions enable you to treat functionality as a method argument, or code as data. Apart from fixing typos and errors, this update includes also includes the following: The Security trail has been restructured; find security information about applets and Java Web Start applications in the Java Applets lesson.

Trails Covering the Basics These trails are available in book form as The Java Tutorial, Fifth Edition. Creating Graphical User Interfaces Specialized Trails and Lessons. SEI CMMI Tutorial. SEI CMMI is a process improvement approach that provides organizations with the essential elements of effective processes. CMMI can help you make decisions about your process improvement plans. This tutorial will give you a very good understanding on SEI CMMI. NOTE: CMMI and CMM are registered in the U.S. Patent and Trademark office by Carnegie Mellon University.

This tutorial has been prepared for the beginners to help them understand basic functionality CMMI approach which is being adopted by various industries to create great quality products at reduced cost. We assume you have little knowledge about Quality Control and Quality Assurance associated terminologies. SEI CMMI Terminology - A Quick Reference A quick reference for all the terms related to SEI CMMI SEI CMMI Glossary A comprehensive list of CMMI Acronyms SEI CMMI Acronyms SEI CMMI Resources A collection of SEI CMMI Sites and Books is given at this page. SEI CMMI Resources. How to extract DNA at home. Webcam. This document describes how to choose, setup and use a webcam in Ubuntu. If you are reading this page, you are probably in either/both of the following situations: Looking for information on which webcam to buy. Trying to setup and use your existing webcam. Please note that this document is intended for the current release: Ubuntu 10.10 (Maverick Meerkat).

Information for earlier versions can be found here. 1. Choosing a Webcam Webcam support in Linux is mainly provided by the Linux UVC Project's UVC driver. 2. Ubuntu aims to provide 'out-of-the-box' or 'just-works' functionality for webcams. Download and install Cheese using the following steps: Open a terminal window. 3. This is a list of software that allows you to do a simple 'plug-in-and-go' test with your webcam. Empathy has been the default VoIP/Video Chat application since Ubuntu 9.10 (Karmic Koala), and can be used to establish whether or not your webcam is working. 3.1. Ls /dev/video* ls /dev/audio* 3.2.1. 3.2.2. 3.3. 3.3.1. 3.4.