88 lines
2.2 KiB
Java
88 lines
2.2 KiB
Java
// generics/Store.java
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// (c)2021 MindView LLC: see Copyright.txt
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// We make no guarantees that this code is fit for any purpose.
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// Visit http://OnJava8.com for more book information.
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// Building a complex model using generic collections
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import java.util.*;
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import java.util.function.*;
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import onjava.*;
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class Product {
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private final int id;
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private String description;
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private double price;
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Product(int idNumber, String descr, double price) {
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id = idNumber;
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description = descr;
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this.price = price;
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System.out.println(toString());
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}
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@Override public String toString() {
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return id + ": " + description +
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", price: $" + price;
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}
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public void priceChange(double change) {
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price += change;
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}
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public static Supplier<Product> generator =
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new Supplier<Product>() {
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private Random rand = new Random(47);
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@Override public Product get() {
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return new Product(rand.nextInt(1000), "Test",
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Math.round(
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rand.nextDouble() * 1000.0) + 0.99);
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}
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};
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}
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class Shelf extends ArrayList<Product> {
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Shelf(int nProducts) {
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Suppliers.fill(this, Product.generator, nProducts);
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}
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}
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class Aisle extends ArrayList<Shelf> {
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Aisle(int nShelves, int nProducts) {
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for(int i = 0; i < nShelves; i++)
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add(new Shelf(nProducts));
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}
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}
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class CheckoutStand {}
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class Office {}
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public class Store extends ArrayList<Aisle> {
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private ArrayList<CheckoutStand> checkouts =
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new ArrayList<>();
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private Office office = new Office();
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public Store(
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int nAisles, int nShelves, int nProducts) {
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for(int i = 0; i < nAisles; i++)
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add(new Aisle(nShelves, nProducts));
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}
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@Override public String toString() {
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StringBuilder result = new StringBuilder();
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for(Aisle a : this)
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for(Shelf s : a)
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for(Product p : s) {
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result.append(p);
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result.append("\n");
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}
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return result.toString();
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}
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public static void main(String[] args) {
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System.out.println(new Store(5, 4, 3));
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}
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}
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/* Output: (First 8 Lines)
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258: Test, price: $400.99
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861: Test, price: $160.99
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868: Test, price: $417.99
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207: Test, price: $268.99
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551: Test, price: $114.99
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278: Test, price: $804.99
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520: Test, price: $554.99
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140: Test, price: $530.99
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...
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*/
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