Introduction
MySQL Connector/J is the official JDBC driver for MySQL. It allows Java applications to connect and interact with MySQL databases using the standard Java Database Connectivity (JDBC) API. It also supports the new X DevAPI, which is a modern, fluent, and intuitive way of working with MySQL as a document store.
MySQL Connector/J is a library that consists of a single jar file that can be added to the classpath of any Java application that needs to communicate with MySQL databases. In this article, we will show you how to download, install, and use MySQL Connector/J 8.0.21 jar file, which is the latest General Availability release of the MySQL Connector/J 8.0 series. We will also discuss some of the benefits and common issues of using this version of the driver.
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Downloading mysql connector java 8.0 21 jar file
To download MySQL Connector/J 8.0.21 jar file, you can visit the official website of MySQL at . You can choose your operating system and platform from the drop-down menus and click on Download.
You will be redirected to a page where you can either sign in or sign up for an Oracle account, or click on No thanks, just start my download link at the bottom of the page. You will then see a pop-up window that shows you the name and size of the file you are about to download.
The file name should be mysql-connector-java-8.0.21.jar and its size should be about 4 MB. You can save it to any location on your computer that you prefer.
Installing mysql connector java 8.0 21 jar file
Adding the jar file to the classpath
After downloading the jar file, you need to add it to the classpath of your Java application so that it can be loaded by the Java runtime environment. There are different ways to do this depending on your development environment and preferences.
One way is to set an environment variable called CLASSPATH that points to the location of the jar file on your computer. For example, if you saved the jar file in C:\mysql-connector-java-8.0.21.jar on Windows, you can set the CLASSPATH variable as follows:
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set CLASSPATH=C:\mysql-connector-java-8.0.21.jar;%CLASSPATH%
This will append the jar file location to the existing classpath value. You can also use a semicolon (;) to separate multiple jar files in the classpath.
Another way is to use the -cp or -classpath option when running your Java application from the command line. For example, if your application is called MyApp.class and it is located in C:\myapp, you can run it as follows:
java -cp C:\mysql-connector-java-8.0.21.jar;C:\myapp MyApp
This will tell the Java runtime environment to look for the jar file and the application class in the specified locations.
A third way is to use your integrated development environment (IDE) settings to add the jar file to the classpath of your project. Different IDEs have different ways of doing this, but usually you can find an option to add external libraries or dependencies to your project. For example, in Eclipse, you can right-click on your project name, select Properties, then Java Build Path, then Libraries, then Add External JARs, and browse to the location of the jar file.
Loading the driver class
After adding the jar file to the classpath, you need to load the driver class that implements the JDBC interface for MySQL. There are two ways to do this:
One way is to use the Class.forName() method with the fully qualified name of the driver class as a parameter. For example:
Class.forName("com.mysql.cj.jdbc.Driver");
This will load and register the driver class with the DriverManager class, which is responsible for managing JDBC drivers and connections.
Another way is to use the DriverManager.registerDriver() method with an instance of the driver class as a parameter. For example:
DriverManager.registerDriver(new com.mysql.cj.jdbc.Driver());
This will also register the driver class with the DriverManager class.
Note that both methods require a try-catch block to handle ClassNotFoundException or SQLException that may occur.
Connecting to MySQL database using mysql connector java 8.0 21 jar file
Creating a connection URL
To connect to a MySQL database using MySQL Connector/J, you need to create a connection URL that specifies the host, port, database name, and other parameters for connecting to MySQL server. The general format of the connection URL is as follows:
jdbc:mysql://[host][:port]/[database][?param1=value1][¶m2=value2][&...]
The host is the name or IP address of the MySQL server. The default port is 3306. The database is the name of the database you want to connect to. The parameters are optional and can be used to customize various aspects of the connection, such as user name, password, character encoding, SSL mode, etc.
For example, a connection URL that connects to a database called test on a local MySQL server with user name root and password root1234 using UTF-8 encoding and SSL mode required would look like this:
jdbc:mysql://localhost:3306/test?user=root&password=root1234&characterEncoding=UTF-8&sslMode=REQUIRED
You can find more information about the connection URL syntax and parameters in .
Obtaining a connection object
To obtain a connection object that represents a physical connection to the MySQL database, you can use one of two methods:
One method is to use the DriverManager.getConnection() method with the connection URL as a parameter. For example:
Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/test?user=root&password=root1234&characterEncoding=UTF-8&sslMode=REQUIRED");
This will return a Connection object that you can use to execute SQL statements and perform other database operations.
Another method is to use a DataSource object that encapsulates the connection information and provides a getConnection() method that returns a Connection object. For example:
MysqlDataSource dataSource = new MysqlDataSource();dataSource.setURL("jdbc:mysql://localhost:3306/test");dataSource.setUser("root");dataSource.setPassword("root1234");dataSource.setCharacterEncoding("UTF-8");dataSource.setSslMode ("REQUIRED");Connection conn = dataSource.getConnection();
This will also return a Connection object that you can use for database operations. Using a DataSource object can be more convenient and flexible than using a connection URL, as you can set and change the connection properties programmatically.
Executing SQL statements
Once you have a Connection object, you can use it to create and execute SQL statements using different types of objects, such as Statement, PreparedStatement, or CallableStatement. These objects represent different ways of executing SQL statements, such as static, parameterized, or stored procedures.
A Statement object is used to execute a static SQL statement that does not have any parameters. For example:
Statement stmt = conn.createStatement();ResultSet rs = stmt.executeQuery("SELECT * FROM users");
This will create a Statement object and execute a query that returns all the records from the users table. The result of the query is stored in a ResultSet object, which can be used to iterate over the rows and columns of the data.
A PreparedStatement object is used to execute a parameterized SQL statement that has one or more placeholders for the values that will be supplied at runtime. For example:
PreparedStatement pstmt = conn.prepareStatement("INSERT INTO users (name, email) VALUES (?, ?)");pstmt.setString(1, "Alice");pstmt.setString(2, "alice@example.com");int rows = pstmt.executeUpdate();
This will create a PreparedStatement object and execute an insert statement that inserts a new record into the users table with the values provided by the setString() methods. The number of affected rows is returned by the executeUpdate() method.
A CallableStatement object is used to execute a stored procedure or function that is defined in the MySQL database. For example:
CallableStatement cstmt = conn.prepareCall("call get_user_count(?)");cstmt.registerOutParameter(1, Types.INTEGER);cstmt.execute();int count = cstmt.getInt(1);
This will create a CallableStatement object and execute a stored procedure called get_user_count that takes one output parameter of type integer. The value of the output parameter is retrieved by the getInt() method.
Handling exceptions
When working with MySQL Connector/J, you may encounter various types of exceptions that indicate errors or problems during database operations. The most common type of exception is SQLException, which is thrown when there is an error in the SQL statement or the communication with the MySQL server. For example:
try // database operations catch (SQLException e) // handle exception e.printStackTrace();
This will catch any SQLException that occurs in the try block and print its stack trace to the standard error stream. You can also use the getMessage(), getSQLState(), and getErrorCode() methods of SQLException to get more information about the error.
Another type of exception is ClassNotFoundException, which is thrown when the driver class cannot be found or loaded by the Java runtime environment. For example:
try Class.forName("com.mysql.cj.jdbc.Driver"); catch (ClassNotFoundException e) // handle exception e.printStackTrace();
This will catch any ClassNotFoundException that occurs when loading the driver class and print its stack trace to the standard error stream. You can also use the getMessage() method of ClassNotFoundException to get more information about the error.
There are other types of exceptions that may occur when using MySQL Connector/J, such as IOException, NullPointerException, IllegalArgumentException, etc. You should always use appropriate try-catch blocks to handle these exceptions and prevent your application from crashing or behaving unexpectedly.
Benefits of mysql connector java 8.0 21 jar file
Using MySQL Connector/J 8.0.21 jar file has many benefits for Java applications that need to connect and interact with MySQL databases. Some of these benefits are:
Compatibility: MySQL Connector/J 8.0.21 jar file is compatible with all MySQL server versions from 5.6 to 8.0, as well as with Java versions from 8 to 15. It also supports both JDBC 4.2 and X DevAPI standards, which means you can use either relational or document-oriented approaches to work with MySQL data.
Performance: MySQL Connector/J 8.0.21 jar file has many performance improvements over previous versions, such as faster connection establishment, better memory management, enhanced caching mechanisms, optimized query execution, etc. It also supports features like connection pooling, load balancing, compression, and failover, which can enhance the scalability and reliability of your application.
Security: MySQL Connector/J 8.0.21 jar file supports various security features to protect your data and communication with MySQL server, such as SSL/TLS encryption, authentication plugins, password hashing, etc. It also supports features like transparent data encryption, data masking, and audit logging, which can help you comply with data privacy and security regulations.
Usability: MySQL Connector/J 8.0.21 jar file has a simple and intuitive API that makes it easy to use for developers of any skill level. It also has a comprehensive documentation and a rich set of examples that can help you learn and troubleshoot any issues that may arise.
Common errors and solutions for mysql connector java 8.0 21 jar file
Despite the benefits of using MySQL Connector/J 8.0.21 jar file, you may encounter some errors or problems that can affect your application performance or functionality. Here are some of the common errors and solutions for mysql connector java 8.0 21 jar file:
Error
Solution
Server configuration denies access
This error occurs when the MySQL server rejects the connection request from the client due to insufficient privileges or incorrect credentials. To solve this error, you need to check and modify the user account and password that you use to connect to the MySQL server, and make sure that the user has the appropriate permissions to access the database and perform the operations that you need.
No suitable driver
This error occurs when the Java runtime environment cannot find or load the driver class that implements the JDBC interface for MySQL. To solve this error, you need to check and verify that the jar file is added to the classpath of your Java application, and that you use the correct name of the driver class when loading it.
Communication link failure
This error occurs when there is a network problem or a timeout that prevents the client from communicating with the MySQL server. To solve this error, you need to check and troubleshoot the network connection between your client and server machines, and adjust the connection parameters such as connectTimeout, socketTimeout, etc., to avoid or handle timeouts.
Conclusion
In this article, we have shown you how to download, install, and use MySQL Connector/J 8.0.21 jar file, which is the latest General Availability release of the MySQL Connector/J 8.0 series. We have also discussed some of the benefits and common issues of using this version of the driver.
MySQL Connector/J is a powerful and versatile library that enables Java applications to connect and interact with MySQL databases using either JDBC or X DevAPI standards. It is compatible with all MySQL server versions from 5.6 to 8.0, as well as with Java versions from 8 to 15. It has many performance improvements, security features, and usability enhancements over previous versions.
If you want to learn more about MySQL Connector/J, you can visit , which is the developer guide of the driver.
FAQs
Here are some frequently asked questions about MySQL Connector/J:
Q: What is the difference between JDBC and X DevAPI?
A: JDBC is a standard Java API that defines how Java applications can access and manipulate relational data using SQL statements. X DevAPI is a new API that defines how Java applications can access and manipulate document-oriented data using CRUD operations.
Q: How can I switch between JDBC and X DevAPI modes?
A: You can switch between JDBC and X DevAPI modes by using different connection URLs. For JDBC mode, you need to use jdbc:mysql:// as the protocol prefix. For X DevAPI mode, you need to use mysqlx:// as the protocol prefix.
Q: How can I update my existing MySQL Connector/J version to 8.0.21?
A: You can update your existing MySQL Connector/J version to 8.0.21 by downloading the new jar file from and replacing it in your classpath. You may also need to update your code to use the new features or fix any compatibility issues.
Q: How can I use MySQL Connector/J with other Java frameworks or libraries?
A: You can use MySQL Connector/J with other Java frameworks or libraries that support JDBC or X DevAPI standards, such as Spring Boot, Hibernate, JPA, etc. You just need to configure the data source or connection provider to use MySQL Connector/J as the driver.
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