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Microsoft JDBC Driver for SQL Server.
/*
* Microsoft JDBC Driver for SQL Server Copyright(c) Microsoft Corporation All rights reserved. This program is made
* available under the terms of the MIT License. See the LICENSE file in the project root for more information.
*/
package com.microsoft.sqlserver.jdbc;
import java.io.Serializable;
import java.text.MessageFormat;
import java.util.logging.Level;
/**
* This class keeps the failover server info and if the mirror has become the primary. For synchronizing better and not
* to keep a lock in the class through a connection open a placeholder class is used to get the failover info in one
* shot. This class should never directly expose its members.
*/
final class FailoverInfo {
private String failoverPartner;
private int portNumber;
private String failoverInstance;
private boolean setUpInfocalled;
// This member is exposed outside for reading, we need to know in advance if the
// failover partner is the currently active server before making a DNS resolution and a connect attempt.
private boolean useFailoverPartner;
boolean getUseFailoverPartner() {
return useFailoverPartner;
}
FailoverInfo(String failover, SQLServerConnection con, boolean actualFailoverPartner) {
failoverPartner = failover;
useFailoverPartner = actualFailoverPartner;
portNumber = -1; // init to -1 to make sure that the user of this class calls the failover check before getting
// the port number.
}
// the members of this class are not exposed so inorder to log we call this function.
void log(SQLServerConnection con) {
if (con.getConnectionLogger().isLoggable(Level.FINE))
con.getConnectionLogger().fine(con.toString() + " Failover server :" + failoverPartner
+ " Failover partner is primary : " + useFailoverPartner);
}
// this function gets the failover server port and sets up the security manager
// note calls to these should be synchronized or guaranteed to happen from only one thread.
private void setupInfo(SQLServerConnection con) throws SQLServerException {
if (setUpInfocalled)
return;
if (0 == failoverPartner.length()) {
portNumber = SQLServerConnection.DEFAULTPORT;
} else {
// 3.3006 get the instance name
int px = failoverPartner.indexOf('\\');
String instancePort;
String instanceValue;
// found the instance name with the severname
if (px >= 0) {
if (con.getConnectionLogger().isLoggable(Level.FINE))
con.getConnectionLogger().fine(con.toString() + " Failover server :" + failoverPartner);
instanceValue = failoverPartner.substring(px + 1, failoverPartner.length());
failoverPartner = failoverPartner.substring(0, px);
con.validateMaxSQLLoginName(SQLServerDriverStringProperty.INSTANCE_NAME.toString(), instanceValue);
failoverInstance = instanceValue;
instancePort = con.getInstancePort(failoverPartner, instanceValue);
try {
portNumber = Integer.parseInt(instancePort);
} catch (NumberFormatException e) {
// Should not get here as the server should give a proper port number anyway.
MessageFormat form = new MessageFormat(SQLServerException.getErrString("R_invalidPortNumber"));
Object[] msgArgs = {instancePort};
SQLServerException.makeFromDriverError(con, null, form.format(msgArgs), null, false);
}
} else
portNumber = SQLServerConnection.DEFAULTPORT;
}
setUpInfocalled = true;
}
synchronized ServerPortPlaceHolder failoverPermissionCheck(SQLServerConnection con,
boolean link) throws SQLServerException {
setupInfo(con);
return new ServerPortPlaceHolder(failoverPartner, portNumber, failoverInstance, link);
}
// Add/replace the failover server,
synchronized void failoverAdd(SQLServerConnection connection, boolean actualUseFailoverPartner,
String actualFailoverPartner) throws SQLServerException {
if (useFailoverPartner != actualUseFailoverPartner) {
if (connection.getConnectionLogger().isLoggable(Level.FINE))
connection.getConnectionLogger()
.fine(connection.toString() + " Failover detected. failover partner=" + actualFailoverPartner);
useFailoverPartner = actualUseFailoverPartner;
}
// The checking for actualUseFailoverPartner may look weird but this is required
// We only change the failoverpartner info when we connect to the primary
// if we connect to the secondary and it sends a failover partner
// we wont store that information.
if (!actualUseFailoverPartner && !failoverPartner.equals(actualFailoverPartner)) {
failoverPartner = actualFailoverPartner;
// new FO partner need to setup again.
setUpInfocalled = false;
}
}
}
// A simple readonly placeholder class to store the current server info.
// We need this class so during a connection open we can keep a copy of the current failover info stable
// This is also used to keep the standalone primary server connection information.
//
final class ServerPortPlaceHolder implements Serializable {
/**
* Always update serialVersionUID when prompted.
*/
private static final long serialVersionUID = 7393779415545731523L;
private final String serverName;
private final int port;
private final String instanceName;
private final boolean checkLink;
private final SQLServerConnectionSecurityManager securityManager;
ServerPortPlaceHolder(String name, int conPort, String instance, boolean fLink) {
serverName = name;
port = conPort;
instanceName = instance;
checkLink = fLink;
securityManager = new SQLServerConnectionSecurityManager(serverName, port);
doSecurityCheck();
}
// accessors
int getPortNumber() {
return port;
}
String getServerName() {
return serverName;
}
String getInstanceName() {
return instanceName;
}
void doSecurityCheck() {
securityManager.checkConnect();
if (checkLink)
securityManager.checkLink();
}
}