Java - Fundamental classes

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.

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Examples from our training material

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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
Objvprim.java	Object to primitive comparison
Ptr.java	To accompany Trans3 demo
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

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.

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