Add JDBC exercise example

README.md

@@ -10,11 +10,12 @@ This repository contains various project exercises, known as `chapters`. Externa
 
 ### Chapters
 
-|             Chapter              |    Description   |
-|----------------------------------|------------------|
-| [Chapter 0](exercises/chapter_0) |    Hello World   |
-| [Chapter 1](exercises/chapter_1) |   HTTP Requests  |
-| [Chapter 2](exercises/chapter_2) | Thymeleaf basics |
+|             Chapter                     |    Description   |
+|-----------------------------------------|------------------|
+| [Chapter 0](exercises/chapter_0)        |    Hello World   |
+| [Chapter 1](exercises/chapter_1)        |   HTTP Requests  |
+| [Chapter 2](exercises/chapter_2)        | Thymeleaf basics |
+| [JDBC](exercises/spring-jdbc-test)      |    JDBC Tests    |
 
 ### Project work
 

exercises/spring-jdbc-test/pom.xml

@@ -0,0 +1,70 @@
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+	<parent>
+		<groupId>org.springframework.boot</groupId>
+		<artifactId>spring-boot-starter-parent</artifactId>
+		<version>2.3.4.RELEASE</version>
+	</parent>
+	<groupId>com.example.sql-test</groupId>
+	<artifactId>SQLTest</artifactId>
+	<version>0.0.1-SNAPSHOT</version>
+	<name>SQL Test</name>
+	<description>Spring SQL connection test</description>
+
+	<properties>
+		<java.version>1.8</java.version>
+	</properties>
+
+	<dependencies>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter</artifactId>
+		</dependency>
+
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-web</artifactId>
+		</dependency>
+
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-thymeleaf</artifactId>
+		</dependency>
+
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-test</artifactId>
+			<scope>test</scope>
+		</dependency>
+
+		<dependency>
+			<groupId>mysql</groupId>
+			<artifactId>mysql-connector-java</artifactId>
+			<scope>runtime</scope>
+		</dependency>
+
+		<dependency>
+    		<groupId>org.springframework.boot</groupId>
+    		<artifactId>spring-boot-starter-jdbc</artifactId>
+		</dependency>
+
+		<dependency>
+  			<groupId>org.springframework.boot</groupId>
+  			<artifactId>spring-boot-starter-validation</artifactId>
+		</dependency>
+
+	</dependencies>
+
+	<build>
+		<plugins>
+			<plugin>
+				<groupId>org.springframework.boot</groupId>
+				<artifactId>spring-boot-maven-plugin</artifactId>
+			</plugin>
+		</plugins>
+		<finalName>${project.artifactId}</finalName>
+	</build>
+
+</project>

exercises/spring-jdbc-test/src/main/java/com/example/sqltest/SqlTestApplication.java

@@ -0,0 +1,57 @@
+package com.example.sqltest;
+
+import java.math.BigDecimal;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.boot.CommandLineRunner;
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.boot.web.servlet.support.SpringBootServletInitializer;
+import org.springframework.context.annotation.Bean;
+
+import com.example.sqltest.model.Customer;
+import com.example.sqltest.model.CustomerDAOImpl;
+
+@SpringBootApplication
+public class SqlTestApplication extends SpringBootServletInitializer {
+	private static final Logger logger = LoggerFactory.getLogger(SqlTestApplication.class);
+
+
+	public static void main(String[] args) {
+		SpringApplication.run(SqlTestApplication.class, args);
+	}
+
+	@Bean
+	public CommandLineRunner CustomerRunner(CustomerDAOImpl customerDAO) {
+
+		return (args) -> {
+
+			logger.info("Deleting old database table entries");
+			customerDAO.dropAll();
+
+			logger.info("Creating new database table entries");
+
+			customerDAO.save(new Customer(
+					"Daniel", "Thyssenlauf",
+					"man", "English",
+					new BigDecimal("0.45"),
+					"danthyf@gmail.com", null
+					));
+
+			customerDAO.save(new Customer(
+					"Janina", "Riikanen",
+					"woman", "Finnish",
+					new BigDecimal("1.74"),
+					"janskuuu@yahoo.com", "+358405341242"
+					));
+
+			logger.info("Created a new database table with the following values");
+			for (Customer customer : customerDAO.findAll()) {
+				logger.info("CUSTOMER table: {}", customer.toString());
+			}
+
+		};
+
+	}
+}

exercises/spring-jdbc-test/src/main/java/com/example/sqltest/model/Customer.java

@@ -0,0 +1,173 @@
+package com.example.sqltest.model;
+
+import java.math.BigDecimal;
+
+import javax.validation.constraints.Max;
+import javax.validation.constraints.Min;
+
+//@Entity
+public class Customer {
+
+	private Long       id;
+
+	private String     firstName;
+	private String     lastName;
+
+	private String     sex;
+
+	private String     language;
+
+	@Min((long) 0.00)
+	@Max((long) 10.00)
+	private BigDecimal engagement;
+
+	private String     email;
+	private String     phone; //Yes, phone number can have other symbols than numbers. Do regex check for input validation
+	// TODO add street address table
+	// TODO add invoices data table (requires a joining table between CUSTOMER & INVOICE tables)
+
+	// Setters
+
+	public void setId(Long id) {
+		this.id = id;
+	}
+
+	public void setFirstName(String firstName) {
+		this.firstName = firstName;
+	}
+
+	public void setLastName(String lastName) {
+		this.lastName = lastName;
+	}
+
+	public void setSex(String sex) {
+		this.sex = sex;
+	}
+
+	public void setLanguage(String language) {
+		this.language = language;
+	}
+
+	public void setEngagement(BigDecimal engagement) {
+		this.engagement = engagement;
+	}
+
+	public void setPhone(String phone) {
+		this.phone = phone;
+	}
+
+	public void setEmail(String email) {
+		this.email = email;
+	}
+
+	// Getters
+
+	public Long getId() {
+		return id;
+	}
+
+	public String getFirstName() {
+		return firstName;
+	}
+
+	public String getLastName() {
+		return lastName;
+	}
+
+	public String getSex() {
+		return sex;
+	}
+
+	public String getLanguage() {
+		return language;
+	}
+
+	public BigDecimal getEngagement() {
+		return engagement;
+	}
+
+	public String getPhone() {
+		return phone;
+	}
+
+	public String getEmail() {
+		return email;
+	}
+
+	// Constructors
+
+	public Customer() {
+		this.id = (long) 0;
+		this.firstName = null;
+		this.lastName = null;
+
+		this.sex = null;
+		this.language = null;
+		this.engagement = null;
+		this.email = null;
+		this.phone = null;
+	}
+
+	public Customer(
+			Long id,
+			String firstName,
+			String lastName,
+
+			String sex,
+			String language,
+			BigDecimal engagement,
+			String email,
+			String phone
+			) {
+
+		this.id = id;
+		this.firstName = firstName;
+		this.lastName = lastName;
+
+		this.sex = sex;
+		this.language = language;
+		this.engagement = engagement;
+		this.email = email;
+		this.phone = phone;
+	}
+
+	public Customer(
+			String firstName,
+			String lastName,
+
+			String sex,
+			String language,
+			BigDecimal engagement,
+			String email,
+			String phone
+			) {
+
+		this.id = (long) 0;
+		this.firstName = firstName;
+		this.lastName = lastName;
+
+		this.sex = sex;
+		this.language = language;
+		this.engagement = engagement;
+		this.email = email;
+		this.phone = phone;
+	}
+
+	// Overrides
+
+	@Override
+	public String toString() {
+		return "[" +
+	"id: "         + this.id         + ", " +
+	"firstname: "  + this.firstName  + ", " +
+	"lastname: "   + this.lastName   + ", " +
+	"sex: "        + this.sex        + ", " +
+	"language: "   + this.language   + ", " +
+	"engagement: " + this.engagement + ", " +
+	"email: "      + this.email      + ", " +
+	"phone: "      + this.phone      +
+	"]";
+
+	}
+
+}

exercises/spring-jdbc-test/src/main/java/com/example/sqltest/model/CustomerDAO.java

@@ -0,0 +1,13 @@
+package com.example.sqltest.model;
+
+import java.util.List;
+
+public interface CustomerDAO {
+
+	public void save(Customer customer);
+
+	public Customer findById(Long id);
+	public List<Customer> findAll();
+	public void dropAll();
+
+}

exercises/spring-jdbc-test/src/main/java/com/example/sqltest/model/CustomerDAOImpl.java

@@ -0,0 +1,86 @@
+package com.example.sqltest.model;
+
+import java.util.List;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.jdbc.core.JdbcTemplate;
+import org.springframework.jdbc.core.RowMapper;
+import org.springframework.stereotype.Repository;
+
+@Repository
+public class CustomerDAOImpl implements CustomerDAO {
+
+	@Autowired
+	private JdbcTemplate jdbcTemplate;
+
+	// Setters
+
+	public void setJdbcTemplate(JdbcTemplate jdbcTemplate) {
+		this.jdbcTemplate = jdbcTemplate;
+	}
+
+	// Getters
+	public JdbcTemplate getJdbcTemplate() {
+		return this.jdbcTemplate;
+	}
+
+	// Abstract methods
+
+	@Override
+	public void save(Customer customer) {
+		String sqlQuery = "INSERT INTO CUSTOMER(" +
+				"firstname"  + "," +
+				"lastname"   + "," +
+				"sex"        + "," +
+				"language"   + "," +
+				"engagement" + "," +
+				"email"      + "," +
+				"phone"      +
+				") VALUES (?,?,?,?,?,?,?)";
+
+		Object[] sqlData = new Object[] {
+				customer.getFirstName(),
+				customer.getLastName(),
+
+				customer.getSex(),
+				customer.getLanguage(),
+				customer.getEngagement(),
+				customer.getEmail(),
+				customer.getPhone()
+		};
+
+		jdbcTemplate.update(sqlQuery, sqlData);
+	}
+
+	@Override
+	public Customer findById(Long id) {
+
+		String sqlQuery = "SELECT * FROM CUSTOMER WHERE ID = ?";
+		Object[] queryData = new Object[] { id };
+
+		RowMapper<Customer> mapper = new CustomerMapper();
+
+		Customer customer = jdbcTemplate.queryForObject(sqlQuery, queryData, mapper);
+
+		return customer;
+	}
+
+	@Override
+	public List<Customer> findAll() {
+
+		String sqlQuery = "SELECT * FROM CUSTOMER";
+		RowMapper<Customer> mapper = new CustomerMapper();
+		List<Customer> customers = jdbcTemplate.query(sqlQuery, mapper);
+
+		return customers;
+	}
+
+	@Override
+	public void dropAll() {
+		String sqlQueryDelete = "DELETE FROM CUSTOMER";
+		String sqlQueryResetId = "ALTER TABLE CUSTOMER AUTO_INCREMENT = 1";
+		jdbcTemplate.execute(sqlQueryDelete);
+		jdbcTemplate.execute(sqlQueryResetId);
+	}
+
+}

exercises/spring-jdbc-test/src/main/java/com/example/sqltest/model/CustomerMapper.java

@@ -0,0 +1,27 @@
+package com.example.sqltest.model;
+
+import java.sql.ResultSet;
+import java.sql.SQLException;
+
+import org.springframework.jdbc.core.RowMapper;
+
+public class CustomerMapper implements RowMapper<Customer> {
+
+	@Override
+	public Customer mapRow(ResultSet resultSet, int rowNum) throws SQLException {
+
+		Customer customer = new Customer();
+		customer.setId(resultSet.getLong("id"));
+		customer.setFirstName(resultSet.getString("firstname"));
+		customer.setLastName(resultSet.getString("lastname"));
+
+		customer.setSex(resultSet.getString("sex"));
+		customer.setLanguage(resultSet.getString("language"));
+		customer.setEngagement(resultSet.getBigDecimal("engagement"));
+		customer.setEmail(resultSet.getNString("email"));
+		customer.setPhone(resultSet.getNString("phone"));
+
+		return customer;
+	}
+
+}

exercises/spring-jdbc-test/src/main/java/com/example/sqltest/web/CustomerController.java

@@ -0,0 +1,35 @@
+package com.example.sqltest.web;
+
+import java.util.List;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Controller;
+import org.springframework.ui.Model;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RequestMethod;
+
+import com.example.sqltest.model.Customer;
+import com.example.sqltest.model.CustomerDAO;
+
+@Controller
+public class CustomerController {
+
+	@Autowired
+	private CustomerDAO customerDAO;
+
+	@RequestMapping(
+			value = "/customers",
+			method = RequestMethod.GET
+			)
+	public String customerWebFormGet(Model dataModel) {
+
+		List<Customer> customers = customerDAO.findAll();
+		dataModel.addAttribute("customers", customers);
+		return "customers";
+	}
+
+	@RequestMapping("*")
+	public String redirectWebForm() {
+		return "redirect:/customers";
+	}
+}

exercises/spring-jdbc-test/src/main/resources/application.properties

@@ -0,0 +1,12 @@
+server.port = 8080
+
+# This MySQL database connection is established to a remote SQL server via SSH tunnel.
+
+spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
+spring.datasource.url=jdbc:mysql://127.0.0.1:3306/MYSQL_DATABASE?useUnicode=true&useJDBCCompliantTimezoneShift=true&useLegacyDatetimeCode=false&serverTimezone=UTC
+spring.datasource.username=MYSQL_USERNAME
+spring.datasource.password=MYSQL_PASSWORD
+spring.datasource.initialization-mode=always
+
+logging.level.org.springframework.jdbc.core.JdbcTemplate=DEBUG
+logging.level.org.springframework.jdbc.core.StatementCreatorUtils=TRACE

exercises/spring-jdbc-test/src/main/resources/schema.sql

@@ -0,0 +1,13 @@
+CREATE TABLE IF NOT EXISTS CUSTOMER (
+    id         INT(4)        NOT NULL UNIQUE AUTO_INCREMENT,
+	firstname  NVARCHAR(30)  DEFAULT NULL,
+	lastname   NVARCHAR(30)  DEFAULT NULL,
+	sex        VARCHAR(10)   DEFAULT NULL,
+	language   VARCHAR(20)   DEFAULT NULL,
+	engagement DECIMAL(5,2)  DEFAULT NULL,
+	email      NVARCHAR(50)  DEFAULT NULL,
+	phone      VARCHAR(25)   DEFAULT NULL,
+	PRIMARY KEY (id)
+    );
+
+CREATE UNIQUE INDEX IF NOT EXISTS `CUSTOMER.id.IDX_UNIQUE` ON CUSTOMER (id ASC);

exercises/spring-jdbc-test/src/main/resources/templates/customers.html

@@ -0,0 +1,38 @@
+<!DOCTYPE html>
+<html lang="en" xmlns:th="http://www.thymeleaf.org">
+<head>
+    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
+
+    <title>Customer SQL data dump</title>
+
+</head>
+<body>
+
+	<h1>Customer SQL data dump</h1>
+	
+	<table>
+	
+		<tr>
+			<th>First Name</th>
+			<th>First Name</th>
+			<th>Sex</th>
+			<th>Language</th>
+			<th>Engagement Level</th>
+			<th>Email Address</th>
+			<th>Phone Number</th>
+		</tr>
+		
+		<tr th:each="customer : ${customers}">
+			<td th:text="${customer.firstName}"></td>
+			<td th:text="${customer.lastName}"></td>
+			<td th:text="${customer.sex}"></td>
+			<td th:text="${customer.language}"></td>
+			<td th:text="${customer.engagement}"></td>
+			<td th:text="${customer.email}"></td>
+			<td th:text="${customer.phone}"></td>
+		</tr>
+	
+	</table>
+
+</body>
+</html>