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Java module J714
Fundamental classes
Exercises, examples and other material relating to training module J714. This topic is presented on public courses Learning to Program in Java, Java Bootcamp, Java Programming for the Web

The java.util package contains many powerful tools for computer scientists, and is an essential element of most Java applications. You'll learn when and how to use stacks, hash tables and many other utility classes. You'll learn how to sort, how to make system calls (and why you shouldn't!), and how to find out more about your environment.

Related technical and longer articles
Want something more dynamic than an array?
Fundamental classes java.lang, java.util and others

Articles and tips on this subjectupdated
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4330Java - factory method, encapsulation, hashmap example
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Examples from our training material
AUtil.java   Creating a hash of objects
About.java   System Properties
Access.java   Access Log analysis / String Tokenizer
Acsort.java   Sorting in Java using the comparable interface
Arlist.java   ArrayList in Java
Bus.java   To accompany Trans3 demo
ByValue.java   Comparator for Trans3 demo
Bynum.java   A Comparator class
Discfree.java   Running an operating system command from Java
Handbag.java   A class in which descructor calls are delayed
Hmap.java   Hashmap example
Hmapsort.java   Sorting in Java - using collections
Hset.java   Hashset example
Mathop.java   Maths operations
Mhs2.java   A further example of sorting in Java
Mypocket.java   Forcing a destructor to run
Network.java   Vector to replace an array
NetworkStation.java   class uses in AUtil demo
Objvprim.java   Object to primitive comparison
Ptr.java   To accompany Trans3 demo
Station.java   Station class used in Network example
Strtok.java   StringTokenizer Example
Thing.java   Example of destructor
Train.java   To accompany Trans3 demo
Trans3.java   ArrayList, Hashmap and Collections sorting
Tshirt.java   Utility classes ArrayList and Hashmap set up to help analyse data file
floater   Float object v float primitive
hinton.java   An Example of a Hashtable
holt.java   Using a Vector object
outmarsh.java   Using a stack
stuff   Data for Trans3 demo
Background information
Some modules are available for download as a sample of our material or under an Open Training Notes License for free download from [here].
Topics covered in this module
The fundamental packages.
Other fundamental packages.
Data wrappers.
Why use data wrappers?.
Other methods on Float objects.
Other methods on other data wrapper objects.
External low-level calls.
The System class - miscellaneous features.
The System class - garbage collection.
The Runtime and Process classes.
A word of caution on system classes.
Utility objects to hold multiple simple objects.
The StringTokenizer.
Iterators and general Collection interfaces.
Basic sorting in Java.
Comparator classes.
The Comparable interface.
Complete learning
If you are looking for a complete course and not just a information on a single subject, visit our Listing and schedule page.

Well House Consultants specialise in training courses in Java,Ruby, Lua, Python, Perl, PHP, and MySQL. We run Private Courses throughout the UK (and beyond for longer courses), and Public Courses at our training centre in Melksham, Wiltshire, England. It's surprisingly cost effective to come on our public courses - even if you live in a different country or continent to us.

We have a technical library of over 700 books on the subjects on which we teach. These books are available for reference at our training centre.

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