回答編集履歴
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DRY
test
CHANGED
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@@ -47,3 +47,79 @@
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}
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```
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###DRY (Do not Repeat Yourself) 追記
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DRY、同じことを繰り返すなという原則。コードを削ります。
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```Java
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abstract class TestClass {
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protected String str;
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protected int num;
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public Object copy() {
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return getInstance(this.str, this.num);
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}
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public static TestClass getInstance(String str, int num) {
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TestClass instance = new TestClass() {};
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instance.str = str;
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instance.num = num;
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return instance;
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}
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}
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```
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###でもね、抽象クラスが必要ですか？
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インスタンスをつくらせたくなければ、コンストラクタをprivateにする方法もあります。自分しかインスタンスを作れない。
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```Java
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public final class TestClass2 {
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protected String str;
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protected int num;
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private TestClass2 () {}
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public Object copy() {
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return getInstance(this.str, this.num);
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}
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public static TestClass2 getInstance(String str, int num) {
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TestClass2 instance = new TestClass2();
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instance.str = str;
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instance.num = num;
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return instance;
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}
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}
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```
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