import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;
public class CheckJDBCInstallation_MySQL {
public static Connection getConnection() throws Exception {
String driver = "org.gjt.mm.mysql.Driver";
String url = "jdbc:mysql://localhost/databaseName";
String username = "root";
String password = "root";
Class.forName(driver); // load MySQL driver
Connection conn = DriverManager.getConnection(url, username, password);
return conn;
}
/**
* Test Validity of JDBC Installation
*
* @param conn
* a JDBC connection object
* @return true if a given connection object is a valid one; otherwise return
* false.
* @throws Exception
* Failed to determine if a given connection is valid.
*/
public static boolean isValidConnection(Connection conn) throws Exception {
if (conn == null) {
// null connection object is not valid
return false;
}
if (conn.isClosed()) {
// closed connection object is not valid
return false;
}
// for MySQL database:
// you may use the connection object
// with query of "select 1"; if the
// query returns the result, then it
// is a valid connection object.
return testConnection(conn, "select 1");
}
/**
* Test Validity of a Connection
*
* @param conn
* a JDBC connection object
* @param query
* a sql query to test against database connection
* @return true if a given connection object is a valid one; otherwise return
* false.
*/
public static boolean testConnection(Connection conn, String query) {
ResultSet rs = null;
Statement stmt = null;
try {
stmt = conn.createStatement();
if (stmt == null) {
return false;
}
rs = stmt.executeQuery(query);
if (rs == null) {
return false;
}
if (rs.next()) {
// connection object is valid: we were able to
// connect to the database and return something useful.
return true;
}
// there is no hope any more for the validity
// of the connection object
return false;
} catch (Exception e) {
//
// something went wrong: connection is bad
//
return false;
} finally {
try {
rs.close();
stmt.close();
conn.close();
} catch (Exception e) {
}
}
}
public static void main(String[] args) {
Connection conn = null;
try {
conn = getConnection();
System.out.println("conn=" + conn);
System.out.println("valid connection = " + isValidConnection(conn));
} catch (Exception e) {
// handle the exception
e.printStackTrace();
System.exit(1);
} finally {
// release database resources
try {
conn.close();
} catch (Exception e) {
}
}
}
}
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