Java - Fundamental classes

Fundamental classes - Java module J714

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.

This topic is presented on public courses Java Programming for the Web, Learning to Program in Java, Java Bootcamp

Examples from our training material

About.java	System Properties
Access.java	Access Log analysis in Java - example
Acsort.java	Sorting in Java using the comparable interface
Arlist.java	ArrayList in Java
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
Objvprim.java	Object to primitive comparison
Strtok.java	StringTokenizer example
Thing.java	Example of destructor
floater	Float object v float primitive
holt.java	Using a Vector object
outmarsh.java	Using a stack

Opentalk forum discussions related to this topic

how to get index of key from hash table
delete occurences of object having simlar property
String Tokenizer
Stream Tokeniser or String TOkenizer
Java date and calendar classes
Dynamic arrays in Java

Background information

This module is available under an Open Training Notes License for free download from http://www.training-notes.co.uk.

Topics covered in this module

The fundamental packages.
java.lang.
java.util.
Other fundamental packages.
Data wrappers.
Why use data wrappers?.
Other methods on Float objects.
Other methods on other data wrapper objects.
java.lang.Math.
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.
Vectors.
Stacks.
Hashes.
Enumerations.
The StringTokenizer.
Collections.
ArrayLists.
HashSets.
Iterators and general Collection interfaces.
HashMaps.
Sorting.
Basic sorting in Java.
Comparator classes.
The Comparable interface.

Course links

The following web pages are used as references / examples in this module

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(at http://www.googlebot.com/bot.html)

We check these links from time to time with a spider written in PHP. Latest full check was on Saturday, 12th June 2004. Titles are extracted from the web pages listed.

Complete learning

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Well House Consultants specialise in training courses in Java,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 600 books on the subjects on which we teach. These books are available for reference at our training centre. Also available is the Opentalk Forum for discussion of technical questions.