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Calling a class - using import to save repeated package names
Packages example from a Well House Consultants training course
More on Packages [link]
Source code: Hilda.java Module: J708
import gowdie.*; // Save need for lots of "gowdie. " stuff!
// Really means "add to path" // Packages equate to directories // classes equate to files // You can put the whole lot into a jar! /* "Too many cooks spoil the broth" "Too many imports cause confusion and conflict" Use imports with care - where you have a lot of references to things in the package being imported. If I see more that 10 imports at the top of a file I get seriously worried java.lang is silently and automatically imported every time */ public class Hilda { public static void main (String [] args) { Isobel [] Pets = new Isobel[4]; Pets[0] = new Isobel("Gypsy",4,7); Pets[1] = new Isobel("Charlie",12); Pets[2] = new Isobel("Billy",5,8); Pets[3] = new Isobel(4,8); for (int p=0; p<Pets.length; p++) { Isobel Halliwell; Halliwell = Pets[p]; float ca = Halliwell.getEffAge(); String nayme = Halliwell.name; System.out.println(nayme+ " is "+ca); } int mouths = Isobel.getCount(); System.out.println("You have " + mouths + " animals"); } } /* Compiler scheme - compile from the top level - PLEASE - some compilers do very peculiar things if you cd in. Here's the right way: wizard:java graham$ javac gowdie/Isobel.java wizard:java graham$ javac Hilda.java wizard:java graham$ javac Hattie.java wizard:java graham$ java Hilda Gypsy is 28.0 Charlie is 72.0 Billy is 40.0 - is 32.0 You have 4 animals wizard:java graham$ Java Hattie Gypsy is 28.0 Charlie is 72.0 Dunno is 40.0 - is 32.0 You have 4 animals wizard:java graham$ ((Largely fixed these days - used to cause hours of headscratching!)) */ Learn about this subject
This module and example are covered on the following public courses:
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