Java - Good Design = Flexible Software: Give Your Software a 30-minuteWorkout(properties, Map, HashMap, Iterator)

Head First Object-Oriented Analysis and Design
A Brain Friendly Guide to OOA&D
(O'Reilly Media)
Brett McLaughlin (著), Gary Pollice (著)
David West (著)
邦訳
Head Firstオブジェクト指向分析設計
頭とからだで覚えるオブジェクト指向の基本
長瀬 嘉秀 (編集), 永田 渉 (編集)
株式会社テクノロジックアート (翻訳)

開発環境

• OS X Yosemite - Apple (OS)
• Emacs (CUI)、BBEdit - Bare Bones Software, Inc. (GUI) (Text Editor)
• Java (プログラミング言語)
• javac (コンパイラ)
• java (application launcher)

Head First Object-Oriented Analysis and Design: A Brain Friendly Guide to OOA&D (Brett McLaughlin (著)、 Gary Pollice (著)、 David West (著) 、 O'Reilly Media)のChapter 5. Good Design = Flexible Software: Give Your Software a 30-minute Workout、CODE MAGNETS(No. 3245)を解いてみる。

その他参考書籍

• Head First Java 第2版 ―頭とからだで覚えるJavaの基本

CODE MAGNETS(No. 3245)

コード(BBEdit, Emacs)

InstrumentSpec.java

import java.util.Map;
import java.util.HashMap;
import java.util.Iterator;

public class InstrumentSpec {
    private Map<String, Object>  properties;

    public InstrumentSpec(Map<String, Object> properties) {
        if (properties == null) {
            this.properties = new HashMap<String, Object>();
        } else {
            this.properties = new HashMap<String, Object>(properties);
        }
    }
    
    public Object getProperty(String propertyName) {
        return properties.get(propertyName);
    }
    
    public Map getProperties() {
        return properties;
    }

    public boolean matches(InstrumentSpec otherSpec) {
        for (Iterator i = otherSpec.getProperties().keySet().iterator();
             i.hasNext();) {
            String propertyName = (String)i.next();
            if (!properties.get(propertyName)
                .equals(otherSpec.getProperty(propertyName))) {
                return false;
            }
        }
        return true;
    }
}

入出力結果(Terminal)

$ javac -Xlint:unchecked InstrumentSpec.java
$