w11 design patterns

w10-patterns/observer/index.js

@@ -0,0 +1,44 @@
+import { Observer, Subject } from './Subject.js';
+
+class Fish {
+  constructor(weight) {
+    super();
+    this.weight = weight;
+  }
+  getWeight() {
+    return this.weight;
+  }
+  getSpecies() {
+    return this.species;
+  }
+}
+
+class Salmon extends Fish {
+  constructor() {
+    super(2);
+    this.species = 'Atalntinc salmon';
+  }
+}
+
+class Tuna extends Fish {
+  constructor() {
+    super(200);
+    this.species = 'Bluefin tuna';
+  }
+}
+
+class Fisherman {
+  constructor(name) {
+    super();
+    this.name = name;
+  }
+}
+
+// Main
+const bob = new Fisherman('Bob');
+
+const fish1 = new Tuna();
+const fish2 = new Salmon();
+// 1. subsribe bob (observer) to fish1 and fish2 (subjects)
+
+// 2. fishes (subjects) notify when they are caught