java 连接mysql的例子

例子程序为：

package outputMml2;//STEP 1. Import required packagesimport java.sql.*;public class Test {    // JDBC driver name and database URL    static final String JDBC_DRIVER = "com.mysql.jdbc.Driver";    static final String DB_URL = "jdbc:mysql://localhost/EMP";    // Database credentials    static final String USER = "username";    static final String PASS = "password";    public static void main( String[] args ) {        Connection conn = null;        PreparedStatement stmt = null;        try {            // STEP 2: Register JDBC driver            Class.forName( "com.mysql.jdbc.Driver" );            // STEP 3: Open a connection            System.out.println( "Connecting to database..." );            conn = DriverManager.getConnection( DB_URL, USER, PASS );            // STEP 4: Execute a query            System.out.println( "Creating statement..." );            String sql = "UPDATE Employees set age=? WHERE id=?";            stmt = conn.prepareStatement( sql );            // Bind values into the parameters.            stmt.setInt( 1, 35 ); // This would set age            stmt.setInt( 2, 102 ); // This would set ID            // Let us update age of the record with ID = 102;            int rows = stmt.executeUpdate();            System.out.println( "Rows impacted : " + rows );            // Let us select all the records and display them.            sql = "SELECT id, first, last, age FROM Employees";            ResultSet rs = stmt.executeQuery( sql );            // STEP 5: Extract data from result set            while ( rs.next() ) {                // Retrieve by column name                int id = rs.getInt( "id" );                int age = rs.getInt( "age" );                String first = rs.getString( "first" );                String last = rs.getString( "last" );                // Display values                System.out.print( "ID: " + id );                System.out.print( ", Age: " + age );                System.out.print( ", First: " + first );                System.out.println( ", Last: " + last );            }            // STEP 6: Clean-up environment            rs.close();            stmt.close();            conn.close();        }        catch ( SQLException se ) {            // Handle errors for JDBC            se.printStackTrace();        }        catch ( Exception e ) {            // Handle errors for Class.forName            e.printStackTrace();        }        finally {            // finally block used to close resources            try {                if ( stmt != null )                    stmt.close();            }            catch ( SQLException se2 ) {            } // nothing we can do            try {                if ( conn != null )                    conn.close();            }            catch ( SQLException se ) {                se.printStackTrace();            } // end finally try        } // end try        System.out.println( "Goodbye!" );    }// end main}// end JDBCExample

程序运行结果为：

Connecting to database...Creating statement...Rows impacted : 1ID: 100, Age: 18, First: Zara, Last: AliID: 101, Age: 25, First: Mahnaz, Last: FatmaID: 102, Age: 35, First: Zaid, Last: KhanID: 103, Age: 30, First: Sumit, Last: MittalGoodbye!

原文出处：http://www.yiibai.com/jdbc/preparestatement-object-example.html