Home Accessibility Courses Twitter The Mouth Facebook Resources Site Map About Us Contact
 
Python and Tcl - public course schedule [here]
Private courses on your site - see [here]
Please ask about maintenance training for Perl, PHP, Lua, etc
 
Java - factory method, encapsulation, hashmap example

Many of the Java examples on our web site that are used to illustrate the utility classes in Java.util are written using String objects as both key and value - however, on the Java course just completed I wrote a somewhat more complex examples to show the relationship between various aspects of the language.

Using a buffered reader, I've read in a series of records from a file and passed each one on to a factory method which analyses that text string and returns an object. Using an accessor method, I extract a text key that I'm going to use to key that object, and I then add the object into a HashMap. See the source code at [here].

The internals of how the input string is converted into an object, and how the properties are accesses, is encapsulated in the class, using a factory method and conventional accessors - see [here].

Once the has map has been set up, my sample program picks out and reports on a chosen element by its key, and I've also demonstrated a set and an iterator to parse the whole Hashmap.

This week, I ran a private Java course for five delegates - 4 days of "Learning to program in Java" - and I thoroughly enjoyed myself. I'm delighted to run such basics courses in Java, although there are so many specialist advanced libraries in Java that we can rarely cover individual customer's detailed specialist requirements these days - hence we no longer offer a standard public course. But please ask if interested!
(written 2014-11-27, updated 2014-11-28)

 
Associated topics are indexed as below, or enter http://melksh.am/nnnn for individual articles
J714 - Java - Fundamental classes
  [4431] A Java servlet that is also a stand alone program. And a server that is also a web client. - (2015-02-19)
  [4421] How healthy are the stars of stage and screen? - (2015-02-09)
  [4396] Java Utility class - flexible replacement for array. Also cacheing in objects and multiple catch clauses example. - (2015-01-16)
  [3048] String handling - from first steps to practical examples - (2010-11-13)
  [2920] Sorting - naturally, or into a different order - (2010-08-14)
  [2734] for and foreach in Java - (2010-04-22)
  [2649] Length, size or capacity in Java? - (2010-02-24)
  [2421] Sorting Collections of Objects in Java - (2009-09-25)
  [2418] Viv.java uses unchecked or unsafe operations - explanation and cure - (2009-09-24)
  [2323] Java Collection Objects in the java.util package - (2009-08-05)
  [1910] Java - Generics - (2008-11-27)
  [1502] Java, sorting, ArrayList example, generics - (2008-01-11)
  [1062] Java sorting - comparable v comparator - (2007-02-02)
  [42] Do languages change? - (2004-09-08)

Q908 - Object Orientation and General technical topics - Object Orientation: Design Patterns
  [4673] Separating detailed data code from the main application - Ruby example - (2016-05-16)
  [4663] Easy data to object mapping (csv and Python) - (2016-03-24)
  [4626] Singleton design pattern - examples and uses - (2016-01-20)
  [4581] Thin application, thick objects - keep you main code simple. Example in Ruby - (2015-11-21)
  [4377] Designing a base class and subclasses, and their extension, in C++ - (2015-01-01)
  [4359] How to avoid too many recalculations within an object - (2014-12-21)
  [4356] Object factories in C++, Python, PHP and Perl - (2014-12-19)
  [4325] Learning to program - what are algorithms and design patterns? - (2014-11-22)
  [4098] Using object orientation for non-physical objects - (2013-05-22)
  [4096] Perl design patterns example - (2013-05-20)
  [4021] Spike solution, refactored and reusable, Python - Example - (2013-02-28)
  [3843] Caching Design Patterns - (2012-08-20)
  [3810] Reading files, and using factories to create vectors of objects from the data in C++ - (2012-07-21)
  [3716] Learning C++ - a design pattern for your first class - (2012-05-02)
  [3608] Design Patterns - what are they? Why use them? - (2012-02-12)
  [2977] What is a factory method and why use one? - Example in Ruby - (2010-09-30)
  [2741] What is a factory? - (2010-04-26)
  [2322] Looking for a practical standards course - (2009-08-05)
  [1224] Object Relation Mapping (ORM) - (2007-06-09)
  [485] North, Norther and Northest - PHP 5 Objects - (2005-11-04)


Back to
Does Santa Claus need a CRB check?
Previous and next
or
Horse's mouth home
Forward to
Musings on a Welsh town
Some other Articles
Splitting out code into name blocks for clarity and reusability
Misty Melksham Morning
First Java Application - calculating the weight of a tablecloth
Musings on a Welsh town
Java - factory method, encapsulation, hashmap example
Does Santa Claus need a CRB check?
Folk music train, Westbury to Swindon round trip, 14th December 2014
Good, stable, reliable local businesses
Learning to program - comments, documentation and test code
4759 posts, page by page
Link to page ... 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96 at 50 posts per page


This is a page archived from The Horse's Mouth at http://www.wellho.net/horse/ - the diary and writings of Graham Ellis. Every attempt was made to provide current information at the time the page was written, but things do move forward in our business - new software releases, price changes, new techniques. Please check back via our main site for current courses, prices, versions, etc - any mention of a price in "The Horse's Mouth" cannot be taken as an offer to supply at that price.

Link to Ezine home page (for reading).
Link to Blogging home page (to add comments).

You can Add a comment or ranking to this page

© WELL HOUSE CONSULTANTS LTD., 2019: 404 The Spa • Melksham, Wiltshire • United Kingdom • SN12 6QL
PH: 01225 708225 • EMAIL: info@wellho.net • WEB: http://www.wellho.net • SKYPE: wellho

PAGE: http://www.wellho.net/mouth/4330_Jav ... ample.html • PAGE BUILT: Sat May 27 16:49:10 2017 • BUILD SYSTEM: WomanWithCat