org.apache.river.norm.LeaseTable Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.river.norm;
import java.util.HashMap;
import java.util.Map;
import net.jini.core.lease.Lease;
/**
* Maps client leases to the wrapper objects that we use internally.
*
* Internally we keep two tables of client leases, one mapping client
* leases to client lease wrappers, the other a list of client lease
* wrappers whose leases could not be unpacked (aka "deformed wrappers")
* when they were added (and thus could not be put in the map). This
* bifurcation is not exposed to the client.
*
* Unless otherwise noted the methods of this class are not thread safe.
*
* @author Sun Microsystems, Inc.
*/
class LeaseTable {
/**
* The list we store deformed wrappers in.
*/
final private DeformedLeaseList deformedLeases = new DeformedLeaseList();
/**
* The map we use to map client leases to wrappers.
*/
final private Map leaseTable = new HashMap();
/**
* Find the client lease wrapper associated with the passed lease.
*
* @param clientLease the lease we need the wrapper for
* @return the wrapper associated with the passed lease, or
* null if we don't know about this lease
*/
ClientLeaseWrapper get(Lease clientLease) {
final ClientLeaseWrapper clw =
(ClientLeaseWrapper) leaseTable.get(clientLease);
if (clw == null) {
/*
* Could it be that this was a lease that could not be
* recovered? Check the deformed list.
*/
return deformedLeases.query(clientLease, leaseTable);
} else {
return clw;
}
}
/**
* Add a mapping from lease wrapper to client lease. Gets client
* lease from wrapper.
*
* @param clw client lease wrapper, and client lease to add to
* table
*/
void put(ClientLeaseWrapper clw) {
if (clw.isDeformed()) {
deformedLeases.add(clw);
} else {
leaseTable.put(clw.getClientLease(), clw);
}
}
/**
* Remove a lease from the table.
*
* @param clw client lease wrapper for the lease we want to
* remove
*/
void remove(ClientLeaseWrapper clw) {
if (!clw.isDeformed()) {
/*
* Not deformed, we need to remove both the client lease and
* the wrapper from the leaseTable.
*/
leaseTable.remove(clw.getClientLease());
} else {
/* Deformed, we need to remove the lease from the deformed
* list.
*/
deformedLeases.remove(clw);
}
}
}