Add all 23 GoF design pattern implementations

03-behavioral/strategy/BubbleSort.java

@@ -0,0 +1,12 @@
+package strategy;
+
+public class BubbleSort implements SortStrategy {
+    @Override
+    public void sort(int[] data) {
+        System.out.println("  [BubbleSort] O(n²) — small arrays only");
+        for (int i = 0; i < data.length - 1; i++)
+            for (int j = 0; j < data.length - 1 - i; j++)
+                if (data[j] > data[j + 1]) { int t = data[j]; data[j] = data[j+1]; data[j+1] = t; }
+    }
+    @Override public String getName() { return "BubbleSort"; }
+}