sample thread example

fishercoder1534 · fishercoder1534 · commit 6b52a0f3cee4 · 2016-08-06T11:06:32.000-07:00
diff --git a/RandomProblems/src/sporadic/thread/HusbandAndWifeJob.java b/RandomProblems/src/sporadic/thread/HusbandAndWifeJob.java
@@ -0,0 +1,68 @@
+package sporadic.thread;
+
+public class HusbandAndWifeJob implements Runnable {
+
+    /*
+     * (non-Javadoc)
+     * 
+     * @see java.lang.Runnable#run()
+     */
+    @Override
+    public void run() {
+        for (int i = 0; i < 10; i++) {
+            makeWithdrawl(10);
+            if (bankAccount.getBalance() < 0) {
+                System.out.println("Overdrawn!!!");
+            }
+        }
+    }
+
+    private BankAccount bankAccount = new BankAccount();
+
+    /**synchronized is the key here to let one thread finish, and then let the other thread to kick in.
+     * Without synchronized this keyword, two threads will invoke this method randomly based on how the OS
+     * scheduler schedules it.*/
+    private synchronized void makeWithdrawl(int amount) {
+        if (bankAccount.getBalance() >= amount) {
+            System.out.println(Thread.currentThread().getName() + " is about to withdraw: " + amount);
+            try {
+                System.out.println(Thread.currentThread().getName() + " is going to sleep.");
+                Thread.sleep(1000);
+            } catch (InterruptedException e) {
+                e.printStackTrace();
+            }
+            System.out.println(Thread.currentThread().getName() + " woke up.");
+            bankAccount.withdraw(amount);
+            System.out.println(Thread.currentThread().getName() + " finished withdrawl: " + amount + "\t now the balance is: " + bankAccount.getBalance());
+        } else {
+            System.out.println("Sorry, not enough balance for " + Thread.currentThread().getName());
+        }
+    }
+
+    /**
+     * @param args
+     */
+    public static void main(String[] args) {
+        HusbandAndWifeJob husbandAndWifeJob = new HusbandAndWifeJob();
+        Thread husband = new Thread(husbandAndWifeJob);
+        Thread wife = new Thread(husbandAndWifeJob);
+        husband.setName("Steve Sun");
+        wife.setName("Sophie Yan");
+        wife.start();
+        husband.start();
+        System.out.println("Program ended.\n\n\n\n\n\n");
+    }
+
+}
+
+class BankAccount {
+    private int balance = 100000;
+
+    public int getBalance() {
+        return balance;
+    }
+
+    public void withdraw(int withdrawAmount) {
+        balance = balance - withdrawAmount;
+    }
+}
diff --git a/RandomProblems/src/sporadic/thread/ThreadIsCool.java b/RandomProblems/src/sporadic/thread/ThreadIsCool.java
@@ -0,0 +1,56 @@
+package sporadic.thread;
+
+/** This is a cool and small program to show that threads don't run in the order that you can control, it's all scheduled by the thing called
+ * Thread Scheduler.*/
+
+public class ThreadIsCool implements Runnable{
+
+	public static void main(String [] args){
+		ThreadIsCool threadIsCool = new ThreadIsCool();
+		Thread abc = new Thread(threadIsCool);
+		Thread def = new Thread(threadIsCool);
+		Thread ghi = new Thread(threadIsCool);
+		abc.setName("abc");
+		def.setName("def");
+		ghi.setName("ghi");
+		System.out.println("Now the three threads kick off:");
+		
+		abc.start();
+		try {
+		    /* Start second thread(def) only when first thread(abc) is dead*/
+            abc.join();
+        } catch (InterruptedException e) {
+            e.printStackTrace();
+        }
+		
+		def.start();
+		try {
+            def.join();
+        } catch (InterruptedException e) {
+            e.printStackTrace();
+        }
+		
+		ghi.start();
+		try {
+            ghi.join();
+        } catch (InterruptedException e) {
+            e.printStackTrace();
+        }
+		System.out.println("Now the Program ended.");
+	}
+	
+	@Override
+	public void run(){
+		for(int i = 0; i < 5; i++){
+			String threadName = Thread.currentThread().getName();
+			System.out.println(threadName + " is running!");
+		}
+		System.out.println(Thread.currentThread().getName() + " is sleeping for 3 seconds");
+		try {
+            Thread.sleep(3000);
+        } catch (InterruptedException e) {
+            e.printStackTrace();
+        }
+	}
+	
+}
