JDK 22のPreviewに対するフィードバックはいつでも歓迎 “The time has come for us to decide what to do about this feature with respect to JDK 23. Given that there is support for a change in the design but a lack of clear consensus on what that new design might look like, the prudent course of action is to (i) NOT ship the current design as a preview feature in JDK 23, and (ii) take our time continuing the design process. We all agree that our favourite language deserves us taking whatever time is needed to perfect our design! Preview features are exactly intended for this - for trying out mature designs before we commit to them for all time. Sometimes we are going to want to change our minds. So, to be clear: there will be no string template feature, even with --enable-preview, in JDK 23. For those of you experimenting with string templates in JDK 22 - please continue to do so, and share your experiences with us. This is the best form of feedback! (We really don’t need, for example, reminders of what other languages do - we have done all that extensive research already. But we don’t know about your application; kick the tires and maybe you’ll unearth something. Play around and send us your feedback - good or bad.)” Update on String Templates (JEP 459) (openjdk.org)
java.desktop; /[ java.awt.Listをエクスポート List l = .[[ /[ どちらを指すかわからないのでエラー /[ Good import java.sql.Date; /[ 明示的に指定（java.util.Dateではなく） Date d = .[[ /[ java.sql.Date
void overriddenMethod() { System.out.println("hello"); } } class Sub extends Super { final int x; Sub(int x) { /* super(); 暗黙の呼び出し */ this.x = x; } @Override void overriddenMethod() { System.out.println(x); } } class JEP482 { public static void main(String... args) { Sub sub = new Sub(42); } }
void overriddenMethod() { System.out.println("hello"); } } class Sub extends Super { final int x; Sub(int x) { /* super(); 暗黙の呼び出し */ this.x = x; } @Override void overriddenMethod() { System.out.println(x); } } class JEP482 { public static void main(String... args) { Sub sub = new Sub(42); } }
overriddenMethod() { System.out.println("hello"); } } class Sub extends Super { final int x; Sub(int x) { this.x = x; // フィールド初期化 super(); // Superのコンストラクタ } @Override void overriddenMethod() { System.out.println(x); } } class JEP482 { public static void main(String... args) { Sub sub = new Sub(42); } }
8 JRE/COMPAT：JDKのレガシーデータコレクション（デフォルト） CLDR：CLDRのデータ システムプロパティ java.locale.providers で選択できる カスタムロケールプロバイダの実装が可能 JDK 9 デフォルトロケールデータプロバイダをCLDRに変更 JDK 21 JRE/COMPAT利用時に警告表示 JDK 23 JRE/COMPATの削除 [JDK-8325568] Remove legacy locale data (COMPAT, JRE) from the JDK - Java Bug System (openjdk.org) JEP 252: Use CLDR Locale Data by Default (openjdk.org) [JDK-8174269] Remove COMPAT locale data provider from JDK - Java Bug System (openjdk.org)
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