From a5320f4fbcba320307aecaa9639e4cf730510cd0 Mon Sep 17 00:00:00 2001
From: haerong22 <haerong22@naver.com>
Date: Mon, 5 Sep 2022 03:02:14 +0900
Subject: [PATCH] #19 was : thread safe

---
 .../java/org/example/counter/Counter.java     | 28 +++++++++++++++++++
 .../example/counter/RaceConditionDemo.java    | 15 ++++++++++
 2 files changed, 43 insertions(+)
 create mode 100644 my-framework/was-practice/src/main/java/org/example/counter/Counter.java
 create mode 100644 my-framework/was-practice/src/main/java/org/example/counter/RaceConditionDemo.java

diff --git a/my-framework/was-practice/src/main/java/org/example/counter/Counter.java b/my-framework/was-practice/src/main/java/org/example/counter/Counter.java
new file mode 100644
index 00000000..a52887d4
--- /dev/null
+++ b/my-framework/was-practice/src/main/java/org/example/counter/Counter.java
@@ -0,0 +1,28 @@
+package org.example.counter;
+
+public class Counter implements Runnable {
+    private int count = 0;
+
+    public void increment() {
+        count++;
+    }
+
+    public void decrement() {
+        count--;
+    }
+
+    public int getValue() {
+        return count;
+    }
+
+    @Override
+    public void run() {
+        synchronized (this) {
+            this.increment();
+            System.out.println("Value for Thread After increment " + Thread.currentThread().getName() + " " + this.getValue());
+
+            this.decrement();
+            System.out.println("Value for Thread at Last " + Thread.currentThread().getName() + " " + this.getValue());
+        }
+    }
+}
diff --git a/my-framework/was-practice/src/main/java/org/example/counter/RaceConditionDemo.java b/my-framework/was-practice/src/main/java/org/example/counter/RaceConditionDemo.java
new file mode 100644
index 00000000..e6940019
--- /dev/null
+++ b/my-framework/was-practice/src/main/java/org/example/counter/RaceConditionDemo.java
@@ -0,0 +1,15 @@
+package org.example.counter;
+
+public class RaceConditionDemo {
+
+    public static void main(String[] args) {
+        Counter counter = new Counter();
+        Thread t1 = new Thread(counter, "Thread-1");
+        Thread t2 = new Thread(counter, "Thread-2");
+        Thread t3 = new Thread(counter, "Thread-3");
+
+        t1.start();
+        t2.start();
+        t3.start();
+    }
+}