JDBC for SQL Server - Herong's Tutorial Examples - v3.13, by Herong Yang
Closing the Database Connection - con.close()
This section describes how to close database connections.
When you obtained a connection object with DriverManager.getConnection() successfully, you can create statement objects and execute them with this connection object. But when you are done with this connection, you should close it to free resources associated this connection on the SQL server. To close a connection, you should call the close() method on this connection object.
The tutorial program below shows you how to call close() on a connection object. isClosed() method is called to verify the status of the connection object.
/* CloseConnection.java
* Copyright (c) HerongYang.com. All Rights Reserved.
*/
import java.sql.*;
public class CloseConnection {
public static void main(String [] args) {
Connection con = null;
try {
// Obtaining a connection to SQL Server
con = DriverManager.getConnection(
"jdbc:sqlserver://localhost\\SQLEXPRESS;"
+ "user=herong;password=T0pSecret");
// Connection is ready to use
DatabaseMetaData meta = con.getMetaData();
System.out.println("Server name: "
+ meta.getDatabaseProductName());
System.out.println("Server version: "
+ meta.getDatabaseProductVersion());
// Closing the connection
con.close();
if (con.isClosed())
System.out.println("Connection closed.");
} catch (Exception e) {
e.printStackTrace();
}
}
}
If you run this program, you will get:
herong> java -cp .;mssql-jdbc-9.4.1.jre16.jar CloseConnection.java Server name: Microsoft SQL Server Server version: 15.00.2000 Connection closed.
Table of Contents
JDBC (Java Database Connectivity) Introduction
Microsoft SQL Server Express Edition
►Microsoft JDBC Driver for SQL Server
Installing Microsoft JDBC Driver for SQL Server
Loading Driver Class Automatically
Loading Driver Class with Class.forName()
DriverManager.getConnection() and Connection URL
Enable TCP/IP with SQL Server Configuration Manager
Specifying Port Number in Connection URL
Instance Name Better than Port Number
Specifying Instance Name in Connection URL
►Closing the Database Connection - con.close()
Specifying Database Name in Connection URL
Incorrect Database Name in Connection URL
Creating Connections with DataSource Class
Microsoft JDBC Driver - Query Statements and Result Sets
Microsoft JDBC Driver - DatabaseMetaData Object
Microsoft JDBC Driver - DDL Statements
Microsoft JDBC Driver - DML Statements
SQL Server - PreparedStatement
SQL Server CLOB (Character Large Object) - TEXT
SQL Server BLOB (Binary Large Object) - BLOB
JDBC-ODBC Bridge Driver - sun.jdbc.odbc.JdbcOdbcDriver
JDBC-ODBC Bridge Driver - Flat Text Files
JDBC-ODBC Bridge Driver - MS Access