Java packaging sample code added.

5 files changed, 103 insertions, 0 deletions

diff --git a/java/09-packages/.gitignore b/java/09-packages/.gitignore
new file mode 100644
index 0000000..e493dd6
--- /dev/null
+++ b/java/09-packages/.gitignore
@@ -0,0 +1,2 @@
+bin
+dist
diff --git a/java/09-packages/README b/java/09-packages/README
new file mode 100644
index 0000000..7618884
--- /dev/null
+++ b/java/09-packages/README
@@ -0,0 +1,14 @@
+# NOTE:
+# On Windows,
+#   1. Use \ as the directory seperator.
+
+# Compile:
+mkdir bin
+javac -d bin src/lk/ac/pdn/ceit/fullstack/*.java
+
+# Build jar file:
+mkdir dist
+jar cfe dist/my-accounts-app.jar lk.ac.pdn.ceit.fullstack.AccountApp -C bin .
+
+# Run
+java -jar dist/my-accounts-app.jar
diff --git a/java/09-packages/src/lk/ac/pdn/ceit/fullstack/Account.java b/java/09-packages/src/lk/ac/pdn/ceit/fullstack/Account.java
new file mode 100644
index 0000000..acc5fe6
--- /dev/null
+++ b/java/09-packages/src/lk/ac/pdn/ceit/fullstack/Account.java
@@ -0,0 +1,28 @@
+package lk.ac.pdn.ceit.fullstack;
+
+public class Account {
+	
+	/* Declaring fields  - represent state */
+	
+	int accountNumber;
+	double balance;
+
+	public Account(int accountNumber, double balance) {
+		this.accountNumber = accountNumber;
+		this.balance = balance;
+	}
+
+	public int getAccountNumber() {
+		return accountNumber;
+	}
+	public void setAccountNumber(int accountNumber) {
+		this.accountNumber = accountNumber;
+	}
+	public double getBalance() {
+		return balance;
+	}
+	public void setBalance(double balance) {
+		this.balance = balance;
+	}
+	
+}
diff --git a/java/09-packages/src/lk/ac/pdn/ceit/fullstack/AccountApp.java b/java/09-packages/src/lk/ac/pdn/ceit/fullstack/AccountApp.java
new file mode 100644
index 0000000..a7736af
--- /dev/null
+++ b/java/09-packages/src/lk/ac/pdn/ceit/fullstack/AccountApp.java
@@ -0,0 +1,18 @@
+package lk.ac.pdn.ceit.fullstack;
+
+public class AccountApp {
+
+	/**
+	 * @param args
+	 */
+	public static void main(String[] args) {
+		AccountManager accountManager = new AccountManager();
+
+		System.out.println(accountManager.getBalance(2));
+
+		accountManager.deposit(2, 2.0);
+
+		System.out.println(accountManager.getBalance(2));
+	}
+
+}
diff --git a/java/09-packages/src/lk/ac/pdn/ceit/fullstack/AccountManager.java b/java/09-packages/src/lk/ac/pdn/ceit/fullstack/AccountManager.java
new file mode 100644
index 0000000..429e0e7
--- /dev/null
+++ b/java/09-packages/src/lk/ac/pdn/ceit/fullstack/AccountManager.java
@@ -0,0 +1,41 @@
+package lk.ac.pdn.ceit.fullstack;
+
+import java.util.HashMap;
+import java.util.Map;
+
+public class AccountManager {
+
+    private Map<Integer, Account> accounts = new HashMap<>();
+
+	/*
+		This is a called a constructor. It gets executed when an object of this class is
+		created.	
+	*/
+    public AccountManager() {
+		// For testing, create some account objects.
+		// In a real systems, account data will be in a storage system like a database.
+
+		Account account = new Account(1, 10.0);
+        accounts.put(account.getAccountNumber(), account);
+
+		account = new Account(2, 20.0);
+        accounts.put(account.getAccountNumber(), account);
+        
+		account = new Account(3, 10.0);
+        accounts.put(account.getAccountNumber(), account);
+    }
+
+	public void withdraw(int accountId, double amount) {
+		Account account = accounts.get(accountId);
+		account.setBalance(account.getBalance() - amount);
+	}
+
+	public void deposit(int accountId, double amount) {
+		Account account = accounts.get(accountId);
+		account.setBalance(account.getBalance() + amount);
+	}
+
+	public double getBalance(int accountId) {
+		return accounts.get(accountId).getBalance();
+	}
+}