implemented strategy pattern

README.md

@@ -14,6 +14,7 @@
     - [Composition](#composition)
 - [Behavioral patterns](#behavioral-patterns)
     - [Chain of responsibility](#chain-of-responsibility)
+    - [Strategy](#strategy)
 - [Concurrency patterns](#concurrency-patterns)
 
 ---
@@ -44,10 +45,15 @@ between objects. Behavio ral patterns describe not just patterns of objects or c
 but also the patterns of communication between them. These patterns characterize
 complex control flow that's difficult to follow at run-time. They shift your focus away
 from flow of control to let you concent ratejust on the way objects are interconnected.
+
 ### Chain of responsibility
 Avoid coupling the sender of a request to its receiver by giving more than one
 object a chance to handle the request. Chain the receiving objects and pass the
 request along the chain until an object handles it.
 
+### Strategy
+Define a family oafl gorit h ms, encapsulate each one, and make them interchangeable.
+Strategy lets the algorithm vary independently from clients that use it.
+
 ## Concurrency patterns
 Pattenrs for concurrent work and parallel execution in Go.

behavioral/strategy/strategy.go

@@ -0,0 +1,34 @@
+package strategy
+
+import (
+	"fmt"
+)
+
+// Abstraction
+type LoggerStrategy interface {
+	Write(string) error
+}
+
+// Strategy 1
+type FileLogger struct {}
+func (l FileLogger) Write(data string) error {
+	fmt.Println("Writed to file...")
+	return nil
+}
+
+// Strategy 2
+type DbLogger struct {}
+func (l DbLogger) Write(data string) error {
+	fmt.Println("Writed to db..")
+}
+
+// Consumer
+type Logger struct{
+	logger LoggerStrategy
+}
+
+func (l *Logger) Log(data string) error {
+	l.logger.Write(data)
+}
+
+