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import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;
public class CheckJDBCInstallation_Oracle {
public static Connection getConnection() throws Exception {
String driver = "oracle.jdbc.driver.OracleDriver";
String url = "jdbc:oracle:thin:@localhost:1521:databaseName";
String username = "name";
String password = "pass";
Class.forName(driver); // load Oracle 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 Oracle database:
// you may use the connection object
// with query of "select 1 from dual";
// if the query returns the result, then
// it is a valid connection object.
return testConnection(conn, "select 1 from dual");
}
/**
* 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) {
return false;
} finally {
// close database resources
try {
rs.close();
stmt.close();
} catch (Exception e) {
// ignore
}
}
}
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) {
// ignore
}
}
}
}
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