Use Java and JDBC with Azure SQL Database
Applies to: Azure SQL Database
This topic demonstrates creating a sample application that uses Java and JDBC to store and retrieve information in Azure SQL Database.
JDBC is the standard Java API to connect to traditional relational databases.
- An Azure account. If you don't have one, get a free trial.
- Azure Cloud Shell or Azure CLI. We recommend Azure Cloud Shell so you'll be logged in automatically and have access to all the tools you'll need.
- A supported Java Development Kit, version 8 (included in Azure Cloud Shell).
- The Apache Maven build tool.
We are going to use environment variables to limit typing mistakes, and to make it easier for you to customize the following configuration for your specific needs.
Set up those environment variables by using the following commands:
AZ_RESOURCE_GROUP=database-workshop
AZ_DATABASE_NAME=<YOUR_DATABASE_NAME>
AZ_LOCATION=<YOUR_AZURE_REGION>
AZ_SQL_SERVER_USERNAME=demo
AZ_SQL_SERVER_PASSWORD=<YOUR_AZURE_SQL_PASSWORD>
AZ_LOCAL_IP_ADDRESS=<YOUR_LOCAL_IP_ADDRESS>
Replace the placeholders with the following values, which are used throughout this article:
<YOUR_DATABASE_NAME>
: The name of your Azure SQL Database server. It should be unique across Azure.<YOUR_AZURE_REGION>
: The Azure region you'll use. You can useeastus
by default, but we recommend that you configure a region closer to where you live. You can have the full list of available regions by enteringaz account list-locations
.<AZ_SQL_SERVER_PASSWORD>
: The password of your Azure SQL Database server. That password should have a minimum of eight characters. The characters should be from three of the following categories: English uppercase letters, English lowercase letters, numbers (0-9), and non-alphanumeric characters (!, $, #, %, and so on).<YOUR_LOCAL_IP_ADDRESS>
: The IP address of your local computer, from which you'll run your Java application. One convenient way to find it is to point your browser to whatismyip.akamai.com.
Next, create a resource group using the following command:
az group create \
--name $AZ_RESOURCE_GROUP \
--location $AZ_LOCATION \
| jq
Note
We use the jq
utility to display JSON data and make it more readable. This utility is installed by default on Azure Cloud Shell. If you don't like that utility, you can safely remove the | jq
part of all the commands we'll use.
The first thing we'll create is a managed logical server for Azure SQL Database.
In Azure Cloud Shell, run the following command:
az sql server create \
--resource-group $AZ_RESOURCE_GROUP \
--name $AZ_DATABASE_NAME \
--location $AZ_LOCATION \
--admin-user $AZ_SQL_SERVER_USERNAME \
--admin-password $AZ_SQL_SERVER_PASSWORD \
| jq
This command creates the logical server for your database.
Azure SQL Database is secured by default since it has a firewall that doesn't allow any incoming connection. To be able to use your database, you need to add a firewall rule that will allow the local IP address to access the database server.
Because you configured our local IP address at the beginning of this article, you can open the server's firewall by running the following command:
az sql server firewall-rule create \
--resource-group $AZ_RESOURCE_GROUP \
--name $AZ_DATABASE_NAME-database-allow-local-ip \
--server $AZ_DATABASE_NAME \
--start-ip-address $AZ_LOCAL_IP_ADDRESS \
--end-ip-address $AZ_LOCAL_IP_ADDRESS \
| jq
The server that you created earlier is empty. It doesn't have any database that you can use with the Java application. Create a new database called demo
by running the following command:
az sql db create \
--resource-group $AZ_RESOURCE_GROUP \
--name demo \
--server $AZ_DATABASE_NAME \
| jq
Using your favorite IDE, create a new Java project, and add a pom.xml
file in its root directory:
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.example</groupId>
<artifactId>demo</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>demo</name>
<properties>
<java.version>17</java.version>
</properties>
<dependencies>
<dependency>
<groupId>com.microsoft.sqlserver</groupId>
<artifactId>mssql-jdbc</artifactId>
<version>12.4.2.jre11</version>
</dependency>
</dependencies>
</project>
This file is an Apache Maven that configures our project to use:
- Java 17
- A recent SQL Server driver for Java
Create a src/main/resources/application.properties file, and add:
url=jdbc:sqlserver://$AZ_DATABASE_NAME.database.windows.net:1433;database=demo;encrypt=true;trustServerCertificate=false;hostNameInCertificate=*.database.windows.net;loginTimeout=30;
user=demo@$AZ_DATABASE_NAME
password=$AZ_SQL_SERVER_PASSWORD
- Replace the two
$AZ_DATABASE_NAME
variables with the value that you configured at the beginning of this article. - Replace the
$AZ_SQL_SERVER_PASSWORD
variable with the value that you configured at the beginning of this article.
We will use a src/main/resources/schema.sql
file in order to create a database schema. Create that file, with the following content:
DROP TABLE IF EXISTS todo;
CREATE TABLE todo (id INT PRIMARY KEY, description VARCHAR(255), details VARCHAR(4096), done BIT);
Next, add the Java code that will use JDBC to store and retrieve data from your Azure SQL database.
Create a src/main/java/com/example/demo/DemoApplication.java file, that contains:
package com.example.demo;
import java.sql.*;
import java.util.*;
import java.util.logging.Logger;
public class DemoApplication {
private static final Logger log;
static {
System.setProperty("java.util.logging.SimpleFormatter.format", "[%4$-7s] %5$s %n");
log =Logger.getLogger(DemoApplication.class.getName());
}
public static void main(String[] args) throws Exception {
log.info("Loading application properties");
Properties properties = new Properties();
properties.load(DemoApplication.class.getClassLoader().getResourceAsStream("application.properties"));
log.info("Connecting to the database");
Connection connection = DriverManager.getConnection(properties.getProperty("url"), properties);
log.info("Database connection test: " + connection.getCatalog());
log.info("Create database schema");
Scanner scanner = new Scanner(DemoApplication.class.getClassLoader().getResourceAsStream("schema.sql"));
Statement statement = connection.createStatement();
while (scanner.hasNextLine()) {
statement.execute(scanner.nextLine());
}
/*
Todo todo = new Todo(1L, "configuration", "congratulations, you have set up JDBC correctly!", true);
insertData(todo, connection);
todo = readData(connection);
todo.setDetails("congratulations, you have updated data!");
updateData(todo, connection);
deleteData(todo, connection);
*/
log.info("Closing database connection");
connection.close();
}
}
This Java code will use the application.properties and the schema.sql files that we created earlier, in order to connect to the SQL Server database and create a schema that will store our data.
In this file, you can see that we commented methods to insert, read, update and delete data: we will code those methods in the rest of this article, and you will be able to uncomment them one after each other.
Note
The database credentials are stored in the user and password properties of the application.properties file. Those credentials are used when executing DriverManager.getConnection(properties.getProperty("url"), properties);
, as the properties file is passed as an argument.
You can now execute this main class with your favorite tool:
- Using your IDE, you should be able to right-click on the DemoApplication class and execute it.
- Using Maven, you can run the application by executing:
mvn package exec:java -Dexec.mainClass="com.example.demo.DemoApplication"
.
The application should connect to the Azure SQL Database, create a database schema, and then close the connection, as you should see in the console logs:
[INFO ] Loading application properties
[INFO ] Connecting to the database
[INFO ] Database connection test: demo
[INFO ] Create database schema
[INFO ] Closing database connection
Create a new Todo
Java class, next to the DemoApplication
class, and add the following code:
package com.example.demo;
public class Todo {
private Long id;
private String description;
private String details;
private boolean done;
public Todo() {
}
public Todo(Long id, String description, String details, boolean done) {
this.id = id;
this.description = description;
this.details = details;
this.done = done;
}
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public String getDescription() {
return description;
}
public void setDescription(String description) {
this.description = description;
}
public String getDetails() {
return details;
}
public void setDetails(String details) {
this.details = details;
}
public boolean isDone() {
return done;
}
public void setDone(boolean done) {
this.done = done;
}
@Override
public String toString() {
return "Todo{" +
"id=" + id +
", description='" + description + '\'' +
", details='" + details + '\'' +
", done=" + done +
'}';
}
}
This class is a domain model mapped on the todo
table that you created when executing the schema.sql script.
In the src/main/java/DemoApplication.java file, after the main method, add the following method to insert data into the database:
private static void insertData(Todo todo, Connection connection) throws SQLException {
log.info("Insert data");
PreparedStatement insertStatement = connection
.prepareStatement("INSERT INTO todo (id, description, details, done) VALUES (?, ?, ?, ?);");
insertStatement.setLong(1, todo.getId());
insertStatement.setString(2, todo.getDescription());
insertStatement.setString(3, todo.getDetails());
insertStatement.setBoolean(4, todo.isDone());
insertStatement.executeUpdate();
}
You can now uncomment the two following lines in the main
method:
Todo todo = new Todo(1L, "configuration", "congratulations, you have set up JDBC correctly!", true);
insertData(todo, connection);
Executing the main class should now produce the following output:
[INFO ] Loading application properties
[INFO ] Connecting to the database
[INFO ] Database connection test: demo
[INFO ] Create database schema
[INFO ] Insert data
[INFO ] Closing database connection
Let's read the data previously inserted, to validate that our code works correctly.
In the src/main/java/DemoApplication.java file, after the insertData
method, add the following method to read data from the database:
private static Todo readData(Connection connection) throws SQLException {
log.info("Read data");
PreparedStatement readStatement = connection.prepareStatement("SELECT * FROM todo;");
ResultSet resultSet = readStatement.executeQuery();
if (!resultSet.next()) {
log.info("There is no data in the database!");
return null;
}
Todo todo = new Todo();
todo.setId(resultSet.getLong("id"));
todo.setDescription(resultSet.getString("description"));
todo.setDetails(resultSet.getString("details"));
todo.setDone(resultSet.getBoolean("done"));
log.info("Data read from the database: " + todo.toString());
return todo;
}
You can now uncomment the following line in the main
method:
todo = readData(connection);
Executing the main class should now produce the following output:
[INFO ] Loading application properties
[INFO ] Connecting to the database
[INFO ] Database connection test: demo
[INFO ] Create database schema
[INFO ] Insert data
[INFO ] Read data
[INFO ] Data read from the database: Todo{id=1, description='configuration', details='congratulations, you have set up JDBC correctly!', done=true}
[INFO ] Closing database connection
Let's update the data we previously inserted.
Still in the src/main/java/DemoApplication.java file, after the readData
method, add the following method to update data inside the database:
private static void updateData(Todo todo, Connection connection) throws SQLException {
log.info("Update data");
PreparedStatement updateStatement = connection
.prepareStatement("UPDATE todo SET description = ?, details = ?, done = ? WHERE id = ?;");
updateStatement.setString(1, todo.getDescription());
updateStatement.setString(2, todo.getDetails());
updateStatement.setBoolean(3, todo.isDone());
updateStatement.setLong(4, todo.getId());
updateStatement.executeUpdate();
readData(connection);
}
You can now uncomment the two following lines in the main
method:
todo.setDetails("congratulations, you have updated data!");
updateData(todo, connection);
Executing the main class should now produce the following output:
[INFO ] Loading application properties
[INFO ] Connecting to the database
[INFO ] Database connection test: demo
[INFO ] Create database schema
[INFO ] Insert data
[INFO ] Read data
[INFO ] Data read from the database: Todo{id=1, description='configuration', details='congratulations, you have set up JDBC correctly!', done=true}
[INFO ] Update data
[INFO ] Read data
[INFO ] Data read from the database: Todo{id=1, description='configuration', details='congratulations, you have updated data!', done=true}
[INFO ] Closing database connection
Finally, let's delete the data we previously inserted.
Still in the src/main/java/DemoApplication.java file, after the updateData
method, add the following method to delete data inside the database:
private static void deleteData(Todo todo, Connection connection) throws SQLException {
log.info("Delete data");
PreparedStatement deleteStatement = connection.prepareStatement("DELETE FROM todo WHERE id = ?;");
deleteStatement.setLong(1, todo.getId());
deleteStatement.executeUpdate();
readData(connection);
}
You can now uncomment the following line in the main
method:
deleteData(todo, connection);
Executing the main class should now produce the following output:
[INFO ] Loading application properties
[INFO ] Connecting to the database
[INFO ] Database connection test: demo
[INFO ] Create database schema
[INFO ] Insert data
[INFO ] Read data
[INFO ] Data read from the database: Todo{id=1, description='configuration', details='congratulations, you have set up JDBC correctly!', done=true}
[INFO ] Update data
[INFO ] Read data
[INFO ] Data read from the database: Todo{id=1, description='configuration', details='congratulations, you have updated data!', done=true}
[INFO ] Delete data
[INFO ] Read data
[INFO ] There is no data in the database!
[INFO ] Closing database connection
Congratulations! You've created a Java application that uses JDBC to store and retrieve data from Azure SQL database.
To clean up all resources used during this quickstart, delete the resource group using the following command:
az group delete \
--name $AZ_RESOURCE_GROUP \
--yes