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Incorporated review changes - 1) Created sql file for central schema 2)

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Changed getById return type to Optional
This commit is contained in:
Narendra Pathai 2016-03-28 11:55:22 +05:30
parent f32a3892a3
commit ddbc61b140
7 changed files with 52 additions and 32 deletions
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5
dao/src/main/java/com/iluwatar/dao/App.java
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@ -73,15 +73,14 @@ public class App {
private static void deleteSchema(DataSource dataSource) throws SQLException {
try (Connection connection = dataSource.getConnection();
Statement statement = connection.createStatement()) {
statement.execute("DROP TABLE CUSTOMERS");
statement.execute(CustomerSchemaSql.DELETE_SCHEMA_SQL);
}
}
private static void createSchema(DataSource dataSource) throws SQLException {
try (Connection connection = dataSource.getConnection();
Statement statement = connection.createStatement()) {
statement.execute("CREATE TABLE CUSTOMERS (ID NUMBER, FNAME VARCHAR(100), "
+ "LNAME VARCHAR(100))");
statement.execute(CustomerSchemaSql.CREATE_SCHEMA_SQL);
}
}

6
dao/src/main/java/com/iluwatar/dao/CustomerDao.java
View File

@ -23,6 +23,7 @@
package com.iluwatar.dao;
import java.util.Optional;
import java.util.stream.Stream;
/**
@ -51,10 +52,11 @@ public interface CustomerDao {
/**
* @param id unique identifier of the customer.
* @return customer with unique identifier <code>id</code> if found, null otherwise.
* @return an optional with customer if a customer with unique identifier <code>id</code>
* exists, empty optional otherwise.
* @throws Exception if any error occurs.
*/
Customer getById(int id) throws Exception;
Optional<Customer> getById(int id) throws Exception;
/**
* @param customer the customer to be added.

9
dao/src/main/java/com/iluwatar/dao/CustomerSchemaSql.java Normal file
View File

@ -0,0 +1,9 @@
package com.iluwatar.dao;
public interface CustomerSchemaSql {
String CREATE_SCHEMA_SQL = "CREATE TABLE CUSTOMERS (ID NUMBER, FNAME VARCHAR(100), "
+ "LNAME VARCHAR(100))";
String DELETE_SCHEMA_SQL = "DROP TABLE CUSTOMERS";
}

9
dao/src/main/java/com/iluwatar/dao/DbCustomerDao.java
View File

@ -27,6 +27,7 @@ import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.Optional;
import java.util.Spliterator;
import java.util.Spliterators;
import java.util.function.Consumer;
@ -109,7 +110,7 @@ public class DbCustomerDao implements CustomerDao {
* {@inheritDoc}
*/
@Override
public Customer getById(int id) throws Exception {
public Optional<Customer> getById(int id) throws Exception {
try (Connection connection = getConnection();
PreparedStatement statement =
connection.prepareStatement("SELECT * FROM CUSTOMERS WHERE ID = ?")) {
@ -117,9 +118,9 @@ public class DbCustomerDao implements CustomerDao {
statement.setInt(1, id);
ResultSet resultSet = statement.executeQuery();
if (resultSet.next()) {
return createCustomer(resultSet);
return Optional.of(createCustomer(resultSet));
} else {
return null;
return Optional.empty();
}
} catch (SQLException ex) {
throw new Exception(ex.getMessage(), ex);
@ -131,7 +132,7 @@ public class DbCustomerDao implements CustomerDao {
*/
@Override
public boolean add(Customer customer) throws Exception {
if (getById(customer.getId()) != null) {
if (getById(customer.getId()).isPresent()) {
return false;
}

7
dao/src/main/java/com/iluwatar/dao/InMemoryCustomerDao.java
View File

@ -25,6 +25,7 @@ package com.iluwatar.dao;
import java.util.HashMap;
import java.util.Map;
import java.util.Optional;
import java.util.stream.Stream;
/**
@ -46,13 +47,13 @@ public class InMemoryCustomerDao implements CustomerDao {
}
@Override
public Customer getById(final int id) {
return idToCustomer.get(id);
public Optional<Customer> getById(final int id) {
return Optional.ofNullable(idToCustomer.get(id));
}
@Override
public boolean add(final Customer customer) {
if (getById(customer.getId()) != null) {
if (getById(customer.getId()).isPresent()) {
return false;
}

23
dao/src/test/java/com/iluwatar/dao/DbCustomerDaoTest.java
View File

@ -46,8 +46,7 @@ public class DbCustomerDaoTest {
public void createSchema() throws SQLException {
try (Connection connection = DriverManager.getConnection(DB_URL);
Statement statement = connection.createStatement()) {
statement.execute("CREATE TABLE CUSTOMERS (ID NUMBER, FNAME VARCHAR(100),"
+ " LNAME VARCHAR(100))");
statement.execute(CustomerSchemaSql.CREATE_SCHEMA_SQL);
}
}
@ -85,7 +84,7 @@ public class DbCustomerDaoTest {
assertTrue(result);
assertCustomerCountIs(2);
assertEquals(nonExistingCustomer, dao.getById(nonExistingCustomer.getId()));
assertEquals(nonExistingCustomer, dao.getById(nonExistingCustomer.getId()).get());
}
@Test
@ -106,12 +105,12 @@ public class DbCustomerDaoTest {
boolean result = dao.update(customer);
assertFalse(result);
assertNull(dao.getById(nonExistingId));
assertFalse(dao.getById(nonExistingId).isPresent());
}
@Test
public void retrieveShouldReturnNull() throws Exception {
assertNull(dao.getById(getNonExistingCustomerId()));
public void retrieveShouldReturnNoCustomer() throws Exception {
assertFalse(dao.getById(getNonExistingCustomerId()).isPresent());
}
}
@ -130,7 +129,7 @@ public class DbCustomerDaoTest {
assertFalse(result);
assertCustomerCountIs(1);
assertEquals(existingCustomer, dao.getById(existingCustomer.getId()));
assertEquals(existingCustomer, dao.getById(existingCustomer.getId()).get());
}
@Test
@ -139,7 +138,7 @@ public class DbCustomerDaoTest {
assertTrue(result);
assertCustomerCountIs(0);
assertNull(dao.getById(existingCustomer.getId()));
assertFalse(dao.getById(existingCustomer.getId()).isPresent());
}
@Test
@ -151,7 +150,7 @@ public class DbCustomerDaoTest {
assertTrue(result);
final Customer cust = dao.getById(existingCustomer.getId());
final Customer cust = dao.getById(existingCustomer.getId()).get();
assertEquals(newFirstname, cust.getFirstName());
assertEquals(newLastname, cust.getLastName());
}
@ -207,12 +206,12 @@ public class DbCustomerDaoTest {
}
@Test
public void retrievingACustomerByIdReturnsNull() throws Exception {
public void retrievingACustomerByIdFailsWithExceptionAsFeedbackToClient() throws Exception {
dao.getById(existingCustomer.getId());
}
@Test
public void retrievingAllCustomersReturnsAnEmptyStream() throws Exception {
public void retrievingAllCustomersFailsWithExceptionAsFeedbackToClient() throws Exception {
dao.getAll();
}
@ -226,7 +225,7 @@ public class DbCustomerDaoTest {
public void deleteSchema() throws SQLException {
try (Connection connection = DriverManager.getConnection(DB_URL);
Statement statement = connection.createStatement()) {
statement.execute("DROP TABLE CUSTOMERS");
statement.execute(CustomerSchemaSql.DELETE_SCHEMA_SQL);
}
}

25
dao/src/test/java/com/iluwatar/dao/InMemoryCustomerDaoTest.java
View File

@ -29,6 +29,7 @@ import static org.junit.Assert.assertNull;
import static org.junit.Assert.assertTrue;
import static org.junit.Assume.assumeTrue;
import java.util.Optional;
import java.util.stream.Stream;
import org.junit.Before;
@ -49,7 +50,7 @@ public class InMemoryCustomerDaoTest {
@Before
public void setUp() {
dao = new InMemoryCustomerDao();
dao.add(CUSTOMER);
assertTrue(dao.add(CUSTOMER));
}
/**
@ -69,7 +70,7 @@ public class InMemoryCustomerDaoTest {
assertTrue(result);
assertCustomerCountIs(2);
assertEquals(nonExistingCustomer, dao.getById(nonExistingCustomer.getId()));
assertEquals(nonExistingCustomer, dao.getById(nonExistingCustomer.getId()).get());
}
@Test
@ -90,12 +91,12 @@ public class InMemoryCustomerDaoTest {
boolean result = dao.update(customer);
assertFalse(result);
assertNull(dao.getById(nonExistingId));
assertFalse(dao.getById(nonExistingId).isPresent());
}
@Test
public void retrieveShouldReturnNull() throws Exception {
assertNull(dao.getById(getNonExistingCustomerId()));
public void retrieveShouldReturnNoCustomer() throws Exception {
assertFalse(dao.getById(getNonExistingCustomerId()).isPresent());
}
}
@ -111,7 +112,7 @@ public class InMemoryCustomerDaoTest {
assertFalse(result);
assertCustomerCountIs(1);
assertEquals(CUSTOMER, dao.getById(CUSTOMER.getId()));
assertEquals(CUSTOMER, dao.getById(CUSTOMER.getId()).get());
}
@Test
@ -120,7 +121,7 @@ public class InMemoryCustomerDaoTest {
assertTrue(result);
assertCustomerCountIs(0);
assertNull(dao.getById(CUSTOMER.getId()));
assertFalse(dao.getById(CUSTOMER.getId()).isPresent());
}
@Test
@ -132,10 +133,18 @@ public class InMemoryCustomerDaoTest {
assertTrue(result);
final Customer cust = dao.getById(CUSTOMER.getId());
final Customer cust = dao.getById(CUSTOMER.getId()).get();
assertEquals(newFirstname, cust.getFirstName());
assertEquals(newLastname, cust.getLastName());
}
@Test
public void retriveShouldReturnTheCustomer() {
Optional<Customer> optionalCustomer = dao.getById(CUSTOMER.getId());
assertTrue(optionalCustomer.isPresent());
assertEquals(CUSTOMER, optionalCustomer.get());
}
}
/**