added Template Method

Author: nicolabovolato

behavioral/template-method/App.ts

@@ -0,0 +1,28 @@
+import { LoggerTemplate, EmailLogger, FileLogger } from "./Templates";
+
+export default class TemplateEx {
+
+    logger1: LoggerTemplate;
+    logger2: LoggerTemplate;
+
+    constructor(){
+
+        this.logger1 = new EmailLogger("john@doe.com","error");
+        this.logger2 = new FileLogger("/logs/app.log","debug");
+        this.run(false);
+        this.run(true);
+    }
+
+    run(runningInContainer: boolean): void {
+
+        console.log("---");
+        if(runningInContainer){
+            this.logger1.log("[FATAL] App crashed");
+        }
+        else{
+            this.logger2.log("[INFO] App started");
+            this.logger2.log("[FATAL] App crashed");
+        }
+
+    }
+}

behavioral/template-method/Templates.ts

@@ -0,0 +1,38 @@
+export abstract class LoggerTemplate {
+
+    loglevel: string;
+
+    constructor(_loglevel: string) {
+        this.loglevel = _loglevel;
+    }
+
+    abstract log(message: string): void;
+}
+
+export class FileLogger extends LoggerTemplate {
+
+    private path: string;
+
+    constructor(_path: string, _loglevel: string) {
+        super(_loglevel);
+        this.path = _path;
+    }
+
+    log(message: string): void {
+        console.log(`Message '${message}' written to ${this.path}`);
+    }
+}
+
+export class EmailLogger extends LoggerTemplate {
+
+    private email: string;
+
+    constructor(_email: string, _loglevel: string) {
+        super(_loglevel);
+        this.email = _email;
+    }
+
+    log(message: string): void {
+        console.log(`Message '${message}' sent to ${this.email}`);
+    }
+}