Added Spring Framework sample code

7 files changed, 392 insertions, 0 deletions

diff --git a/spring-framework/08-bank-jdbc-servlet-webapp/src/main/java/com/example/spring/bank/Account.java b/spring-framework/08-bank-jdbc-servlet-webapp/src/main/java/com/example/spring/bank/Account.java
new file mode 100644
index 0000000..6222af8
--- /dev/null
+++ b/spring-framework/08-bank-jdbc-servlet-webapp/src/main/java/com/example/spring/bank/Account.java
@@ -0,0 +1,21 @@
+package com.example.spring.bank;
+
+import java.math.BigDecimal;
+
+public class Account {
+	private int accountNumber;
+	private BigDecimal balance;
+	
+	public int getAccountNumber() {
+		return accountNumber;
+	}
+	public void setAccountNumber(int accountNumber) {
+		this.accountNumber = accountNumber;
+	}
+	public BigDecimal getBalance() {
+		return balance;
+	}
+	public void setBalance(BigDecimal balance) {
+		this.balance = balance;
+	}
+}
diff --git a/spring-framework/08-bank-jdbc-servlet-webapp/src/main/java/com/example/spring/bank/AccountManager.java b/spring-framework/08-bank-jdbc-servlet-webapp/src/main/java/com/example/spring/bank/AccountManager.java
new file mode 100644
index 0000000..f299d60
--- /dev/null
+++ b/spring-framework/08-bank-jdbc-servlet-webapp/src/main/java/com/example/spring/bank/AccountManager.java
@@ -0,0 +1,21 @@
+package com.example.spring.bank;
+
+import java.math.BigDecimal;
+
+public interface AccountManager {
+
+	public Account create();
+	
+	public Account find(int accountNumber);
+	
+	public Account deposit(int accountNumber, BigDecimal amount);
+	public Account withdraw(int accountNumber, BigDecimal amount);
+	
+	public void delete(int accountNumber);
+	
+	/** Returns the first account */
+	public Account transfer(int accountNumber1, int accountNumber2, BigDecimal amount);
+
+	public void chargeForLowBalance(BigDecimal minimumBalance, BigDecimal amount);
+	
+}
diff --git a/spring-framework/08-bank-jdbc-servlet-webapp/src/main/java/com/example/spring/bank/AccountManagerImpl.java b/spring-framework/08-bank-jdbc-servlet-webapp/src/main/java/com/example/spring/bank/AccountManagerImpl.java
new file mode 100644
index 0000000..39dc63e
--- /dev/null
+++ b/spring-framework/08-bank-jdbc-servlet-webapp/src/main/java/com/example/spring/bank/AccountManagerImpl.java
@@ -0,0 +1,73 @@
+package com.example.spring.bank;
+
+import java.math.BigDecimal;
+import java.util.Iterator;
+import java.util.List;
+
+import com.example.spring.bank.dao.AccountDAO;
+
+public class AccountManagerImpl implements AccountManager {
+
+	private AccountDAO accountDAO;
+	
+	public void setAccountDAO(AccountDAO accountDAO) {
+		this.accountDAO = accountDAO;
+	}
+
+	@Override
+	public void chargeForLowBalance(BigDecimal minimumBalance, BigDecimal amount) {
+		List<Account> accounts = accountDAO.findAccountsWithLowBalance(minimumBalance);
+		for (Iterator<Account> iterator = accounts.iterator(); iterator.hasNext();) {
+			Account account = (Account) iterator.next();
+			// Check if the balance will go beyond 0. If yes, set the balance to 0
+			account.setBalance(account.getBalance().subtract(amount));
+			accountDAO.update(account);
+		}
+	}
+
+	@Override
+	public Account create() {
+		return accountDAO.createAccount();
+	}
+
+	@Override
+	public Account find(int accountNumber) {
+		return accountDAO.getAccount(accountNumber);
+	}
+	
+	@Override
+	public void delete(int accountNumber) {
+		accountDAO.delete(accountNumber);
+	}
+
+	@Override
+	public Account deposit(int accountNumber, BigDecimal amount) {
+		Account account = accountDAO.getAccount(accountNumber);
+		account.setBalance(account.getBalance().add(amount));
+		accountDAO.update(account);
+		
+		return account;
+	}
+
+	@Override
+	public Account withdraw(int accountNumber, BigDecimal amount) {
+		Account account = accountDAO.getAccount(accountNumber);
+		account.setBalance(account.getBalance().subtract(amount));
+		accountDAO.update(account);
+		
+		return account;
+	}
+	
+	@Override
+	public Account transfer(int accountNumber1, int accountNumber2, BigDecimal amount) {
+		Account account1 = accountDAO.getAccount(accountNumber1);
+		account1.setBalance(account1.getBalance().subtract(amount));
+		accountDAO.update(account1);
+		
+		Account account2 = accountDAO.getAccount(accountNumber2);
+		account2.setBalance(account2.getBalance().add(amount));
+		accountDAO.update(account2);
+		
+		return account1;
+	}
+}
\ No newline at end of file
diff --git a/spring-framework/08-bank-jdbc-servlet-webapp/src/main/java/com/example/spring/bank/dao/AccountDAO.java b/spring-framework/08-bank-jdbc-servlet-webapp/src/main/java/com/example/spring/bank/dao/AccountDAO.java
new file mode 100644
index 0000000..735aed2
--- /dev/null
+++ b/spring-framework/08-bank-jdbc-servlet-webapp/src/main/java/com/example/spring/bank/dao/AccountDAO.java
@@ -0,0 +1,15 @@
+package com.example.spring.bank.dao;
+
+import java.math.BigDecimal;
+import java.util.List;
+
+import com.example.spring.bank.Account;
+
+public interface AccountDAO {
+	public Account createAccount();
+	public Account getAccount(int accountNumber);
+	public void update(Account account);
+	public void delete(int accountNumber);
+	public List<Account> findAllAccounts();
+	public List<Account> findAccountsWithLowBalance(BigDecimal lessThanAmount);
+}
diff --git a/spring-framework/08-bank-jdbc-servlet-webapp/src/main/java/com/example/spring/bank/dao/jdbc/JDBCAccountDAO.java b/spring-framework/08-bank-jdbc-servlet-webapp/src/main/java/com/example/spring/bank/dao/jdbc/JDBCAccountDAO.java
new file mode 100644
index 0000000..d285a89
--- /dev/null
+++ b/spring-framework/08-bank-jdbc-servlet-webapp/src/main/java/com/example/spring/bank/dao/jdbc/JDBCAccountDAO.java
@@ -0,0 +1,94 @@
+package com.example.spring.bank.dao.jdbc;
+
+import java.math.BigDecimal;
+import java.sql.Connection;
+import java.sql.PreparedStatement;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+import java.util.List;
+
+import javax.sql.DataSource;
+
+import org.springframework.jdbc.core.JdbcTemplate;
+import org.springframework.jdbc.core.PreparedStatementCreator;
+import org.springframework.jdbc.core.RowMapper;
+import org.springframework.jdbc.support.GeneratedKeyHolder;
+import org.springframework.jdbc.support.KeyHolder;
+
+import com.example.spring.bank.Account;
+import com.example.spring.bank.dao.AccountDAO;
+
+public class JDBCAccountDAO implements AccountDAO {
+
+	private JdbcTemplate jdbcTemplate;
+
+    public void setDataSource(DataSource dataSource) {
+        this.jdbcTemplate = new JdbcTemplate(dataSource);
+    }
+
+	
+	@Override
+	public Account createAccount() {
+//		Connection con = dataSource.getConnection();
+//		PreparedStatement stmt = con.prepareStatement("...", autoGeneratedKeys);
+//		stmt.execute();
+//		con.close();
+		
+		
+		final String INSERT_SQL = "insert into account (balance) values(0)";
+
+		KeyHolder keyHolder = new GeneratedKeyHolder();
+		jdbcTemplate.update(
+		    new PreparedStatementCreator() {
+		        public PreparedStatement createPreparedStatement(Connection connection) throws SQLException {
+		            PreparedStatement ps =
+		                connection.prepareStatement(INSERT_SQL, new String[] {"account_number"});
+		            //  ps.setString(1, name);
+		            return ps;
+		        }
+		    }, keyHolder);
+
+		Account account = new Account();
+		// keyHolder.getKey() now contains the generated key
+		account.setAccountNumber(keyHolder.getKey().intValue());
+		account.setBalance(new BigDecimal("0.0"));
+
+		return account;
+	}
+
+	@Override
+	public void delete(int accountNumber) {
+		jdbcTemplate.update("delete from account where account_number = ?", Integer.valueOf(accountNumber));
+	}
+
+	@Override
+	public List<Account> findAccountsWithLowBalance(BigDecimal lessThanAmount) {
+		return this.jdbcTemplate.query( "select * from account where balance < ?", new Object[] {lessThanAmount.doubleValue()}, new AccountMapper());
+	}
+
+	@Override
+	public List<Account> findAllAccounts() {
+		return this.jdbcTemplate.query( "select * from account", new AccountMapper());
+	}
+
+	@Override
+	public Account getAccount(int accountNumber) {
+		return this.jdbcTemplate.queryForObject( "select * from account where account_number = ?", new Object[] {accountNumber}, new AccountMapper());
+	}
+
+	@Override
+	public void update(Account account) {
+		this.jdbcTemplate.update("update account set balance = ? where account_number = ?", account.getBalance(), account.getAccountNumber());
+	}
+
+	
+	private static final class AccountMapper implements RowMapper<Account> {
+
+	    public Account mapRow(ResultSet rs, int rowNum) throws SQLException {
+	        Account account = new Account();
+	        account.setAccountNumber(rs.getInt("account_number"));
+	        account.setBalance(rs.getBigDecimal("balance"));
+	        return account;
+	    }        
+	}
+}
\ No newline at end of file
diff --git a/spring-framework/08-bank-jdbc-servlet-webapp/src/main/java/com/example/spring/bank/tx/TxAccountManager.java b/spring-framework/08-bank-jdbc-servlet-webapp/src/main/java/com/example/spring/bank/tx/TxAccountManager.java
new file mode 100644
index 0000000..a5b310d
--- /dev/null
+++ b/spring-framework/08-bank-jdbc-servlet-webapp/src/main/java/com/example/spring/bank/tx/TxAccountManager.java
@@ -0,0 +1,109 @@
+package com.example.spring.bank.tx;
+
+import java.math.BigDecimal;
+
+import org.springframework.jdbc.datasource.DataSourceTransactionManager;
+import org.springframework.transaction.TransactionStatus;
+import org.springframework.transaction.support.TransactionCallback;
+import org.springframework.transaction.support.TransactionCallbackWithoutResult;
+import org.springframework.transaction.support.TransactionTemplate;
+
+import com.example.spring.bank.Account;
+import com.example.spring.bank.AccountManager;
+
+/**
+ * This class decorates a given AccountManager by adding transaction boundaries.
+ * 
+ * @author kamal
+ *
+ */
+public class TxAccountManager implements AccountManager {
+
+	private AccountManager accountManager;
+
+	public void setAccountManager(AccountManager accountManager) {
+		this.accountManager = accountManager;
+	}
+
+	private TransactionTemplate txTemplate;
+
+	public void setTxManager(DataSourceTransactionManager txManager) {
+		txTemplate = new TransactionTemplate(txManager);
+	}
+
+	@Override
+	public Account create() {
+		return txTemplate.execute(new TransactionCallback<Account>() {
+			@Override
+			public Account doInTransaction(TransactionStatus arg0) {
+				return accountManager.create();
+			}
+		});
+	}
+	
+	@Override
+	public Account find(int accountNumber) {
+		return accountManager.find(accountNumber);
+	}
+
+	@Override
+	public Account deposit(int accountNumber, BigDecimal amount) {
+		return txTemplate.execute(new TransactionCallback<Account>() {
+
+			@Override
+			public Account doInTransaction(TransactionStatus arg0) {
+				return accountManager.deposit(accountNumber, amount);
+			}
+		});
+	}
+
+	@Override
+	public Account withdraw(int accountNumber, BigDecimal amount) {
+		return txTemplate.execute(new TransactionCallback<Account>() {
+
+			@Override
+			public Account doInTransaction(TransactionStatus arg0) {
+				return accountManager.withdraw(accountNumber, amount);
+			}
+		});
+	}
+
+	@Override
+	public void delete(int accountNumber) {
+		txTemplate.execute(new TransactionCallbackWithoutResult() {
+
+			@Override
+			protected void doInTransactionWithoutResult(TransactionStatus arg0) {
+				accountManager.delete(accountNumber);
+			}
+		});
+	}
+
+	@Override
+	public void chargeForLowBalance(BigDecimal minimumBalance, BigDecimal amount) {
+		txTemplate.execute(new TransactionCallbackWithoutResult() {
+
+			@Override
+			protected void doInTransactionWithoutResult(TransactionStatus arg0) {
+				accountManager.chargeForLowBalance(minimumBalance, amount);
+			}
+		});
+	}
+
+	@Override
+	public Account transfer(int accountNumber1, int accountNumber2, BigDecimal amount) {
+		return txTemplate.execute(new TransactionCallback<Account>() {
+
+			@Override
+			public Account doInTransaction(TransactionStatus status) {
+				try {
+					return accountManager.transfer(accountNumber1, accountNumber2, amount);
+				} catch (Exception e) {
+					// Some exception occurred.
+					status.setRollbackOnly();
+					throw e;
+				}
+			}
+		});
+	}
+}
diff --git a/spring-framework/08-bank-jdbc-servlet-webapp/src/main/java/com/example/spring/bank/web/BankGateway.java b/spring-framework/08-bank-jdbc-servlet-webapp/src/main/java/com/example/spring/bank/web/BankGateway.java
new file mode 100644
index 0000000..e7908d5
--- /dev/null
+++ b/spring-framework/08-bank-jdbc-servlet-webapp/src/main/java/com/example/spring/bank/web/BankGateway.java
@@ -0,0 +1,59 @@
+package com.example.spring.bank.web;
+
+import java.io.IOException;
+import java.math.BigDecimal;
+
+import javax.servlet.ServletException;
+import javax.servlet.http.HttpServlet;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+
+import org.springframework.web.context.WebApplicationContext;
+import org.springframework.web.context.support.WebApplicationContextUtils;
+
+import com.example.spring.bank.AccountManager;
+
+/**
+ * Servlet implementation class BankGateway
+ */
+public class BankGateway extends HttpServlet {
+	private static final long serialVersionUID = 1L;
+       
+    /**
+     * @see HttpServlet#HttpServlet()
+     */
+    public BankGateway() {
+        super();
+    }
+
+	/**
+	 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
+	 */
+	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
+		getServletContext().getRequestDispatcher("/deposit.jsp").forward(request, response);
+	}
+
+	/**
+	 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
+	 */
+	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
+		WebApplicationContext ctx = WebApplicationContextUtils.getWebApplicationContext(getServletContext());
+		AccountManager am = ctx.getBean("accountManager", AccountManager.class);
+		
+		int accountNumber = Integer.parseInt(request.getParameter("accountNumber"));
+		BigDecimal amount = new BigDecimal(request.getParameter("amount"));
+		
+		// How to use a session scoped bean (Example only)
+//		DepositForm form = (DepositForm) ctx.getBean("depositForm");
+//		form.setAccountNumber(accountNumber);
+//		form.setAmount(amount);
+		// End of example
+		
+		
+		am.deposit(accountNumber, amount);
+		
+		// We can dispatch to a success page if we prefer!
+		getServletContext().getRequestDispatcher("/deposit.jsp").forward(request, response);
+	}
+
+}