/*
* Copyright (c) 2004, PostgreSQL Global Development Group
* See the LICENSE file in the project root for more information.
*/
// Copyright (c) 2004, Open Cloud Limited.
package org.postgresql.core;
import org.postgresql.
PGProperty;
import org.postgresql.core.v3.
ConnectionFactoryImpl;
import org.postgresql.util.
GT;
import org.postgresql.util.
HostSpec;
import org.postgresql.util.
PSQLException;
import org.postgresql.util.
PSQLState;
import java.io.
IOException;
import java.sql.
SQLException;
import java.util.
Properties;
/**
* Handles protocol-specific connection setup.
*
* @author Oliver Jowett (oliver@opencloud.com)
*/
public abstract class
ConnectionFactory {
/**
* <p>Establishes and initializes a new connection.</p>
*
* <p>If the "protocolVersion" property is specified, only that protocol version is tried. Otherwise,
* all protocols are tried in order, falling back to older protocols as necessary.</p>
*
* <p>Currently, protocol versions 3 (7.4+) is supported.</p>
*
* @param hostSpecs at least one host and port to connect to; multiple elements for round-robin
* failover
* @param user the username to authenticate with; may not be null.
* @param database the database on the server to connect to; may not be null.
* @param info extra properties controlling the connection; notably, "password" if present
* supplies the password to authenticate with.
* @return the new, initialized, connection
* @throws SQLException if the connection could not be established.
*/
public static
QueryExecutor openConnection(
HostSpec[]
hostSpecs,
String user,
String database,
Properties info) throws
SQLException {
String protoName =
PGProperty.
PROTOCOL_VERSION.
get(
info);
if (
protoName == null ||
protoName.
isEmpty() || "3".
equals(
protoName)) {
ConnectionFactory connectionFactory = new
ConnectionFactoryImpl();
QueryExecutor queryExecutor =
connectionFactory.
openConnectionImpl(
hostSpecs,
user,
database,
info);
if (
queryExecutor != null) {
return
queryExecutor;
}
}
throw new
PSQLException(
GT.
tr("A connection could not be made using the requested protocol {0}.",
protoName),
PSQLState.
CONNECTION_UNABLE_TO_CONNECT);
}
/**
* Implementation of {@link #openConnection} for a particular protocol version. Implemented by
* subclasses of {@link ConnectionFactory}.
*
* @param hostSpecs at least one host and port to connect to; multiple elements for round-robin
* failover
* @param user the username to authenticate with; may not be null.
* @param database the database on the server to connect to; may not be null.
* @param info extra properties controlling the connection; notably, "password" if present
* supplies the password to authenticate with.
* @return the new, initialized, connection, or <code>null</code> if this protocol version is not
* supported by the server.
* @throws SQLException if the connection could not be established for a reason other than
* protocol version incompatibility.
*/
public abstract
QueryExecutor openConnectionImpl(
HostSpec[]
hostSpecs,
String user,
String database,
Properties info) throws
SQLException;
/**
* Safely close the given stream.
*
* @param newStream The stream to close.
*/
protected void
closeStream(
PGStream newStream) {
if (
newStream != null) {
try {
newStream.
close();
} catch (
IOException e) {
}
}
}
}