Add java17-features module: runnable demos and captured output for the ankurm.com java17-features article

2026-10-20 17:13:58 +00:00
parent 8b9447a393
commit 5a076c826f
23 changed files with 261 additions and 0 deletions
@@ -0,0 +1,16 @@
+/** Pattern matching for instanceof (final in 16, JEP 394) and Stream.toList() (16). */
+public class PatternInstanceofDemo {
+    static String describe(Object o) {
+        if (o instanceof String s && s.length() > 3) return "long string " + s;
+        if (o instanceof Integer i) return "int " + (i + 1);
+        return "other " + o;
+    }
+    public static void main(String[] args) {
+        System.out.println(describe("hello"));
+        System.out.println(describe("hi"));
+        System.out.println(describe(41));
+        var list = java.util.stream.Stream.of(3, 1, 2).sorted().toList();
+        System.out.println("Stream.toList   : " + list);
+        try { list.add(4); } catch (UnsupportedOperationException e) { System.out.println("toList() result is unmodifiable"); }
+    }
+}