/*
* 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.geode.distributed.internal.locks;
import org.apache.geode.distributed.internal.DM;
import org.apache.geode.distributed.internal.DistributionConfig;
import org.apache.geode.distributed.internal.membership.InternalDistributedMember;
import org.apache.geode.internal.i18n.LocalizedStrings;
/**
* Identifies specific lock grantor member and version.
*
* @since GemFire 5.1
*/
public class LockGrantorId {
public static final int ROLLOVER_MARGIN = Integer
.getInteger(DistributionConfig.GEMFIRE_PREFIX + "DLockService.LockGrantorId.rolloverMargin",
10000)
.intValue();
private final DM dm;
private final InternalDistributedMember lockGrantorMember;
private final long lockGrantorVersion;
private final int lockGrantorSerialNumber;
/**
* Constructs a new instance to identify a specific lock grantor member and version.
*
* @param dm the distribution manager which is used by {@link #isLocal()}
* @param lockGrantorMember the non-null member hosting the grantor
* @param lockGrantorVersion the long grantor version number
*/
public LockGrantorId(DM dm, InternalDistributedMember lockGrantorMember, long lockGrantorVersion,
int lockGrantorSerialNumber) {
if (lockGrantorMember == null) {
throw new NullPointerException(
LocalizedStrings.LockGrantorId_LOCKGRANTORMEMBER_IS_NULL.toLocalizedString());
}
this.dm = dm;
this.lockGrantorMember = lockGrantorMember;
this.lockGrantorVersion = lockGrantorVersion;
this.lockGrantorSerialNumber = lockGrantorSerialNumber;
}
/**
* Returns the non-null member hosting the grantor.
*
* @return the member hosting the grantor
*/
public InternalDistributedMember getLockGrantorMember() {
return this.lockGrantorMember;
}
/**
* Returns the long grantor version number. A given member may host grantor several times during
* its life and this version number will be greater for later grantor instances.
*
* @return the long grantor version number
*/
public long getLockGrantorVersion() {
return this.lockGrantorVersion;
}
/**
* Returns the DLS serial number of the lock service that is hosting the grantor.
*
* @return the grantor's DLS serial number
*/
public int getLockGrantorSerialNumber() {
return this.lockGrantorSerialNumber;
}
/**
* Returns true if the grantor version number is positive.
*
* @return true if the grantor version number is positive
*/
public boolean hasLockGrantorVersion() {
return this.lockGrantorVersion > -1;
}
/**
* Returns true if <code>otherLockGrantorId</code> is same as this instance. Returns false if
* different or if <code>otherLockGrantorId</code> is null.
*
* @param otherLockGrantorId the other instance to compare this instance to
* @return true if <code>otherLockGrantorId</code> is same
*/
public boolean sameAs(LockGrantorId otherLockGrantorId) {
if (otherLockGrantorId == null) {
return false;
}
return sameAs(otherLockGrantorId.lockGrantorMember, otherLockGrantorId.lockGrantorVersion,
otherLockGrantorId.lockGrantorSerialNumber);
}
/**
* Returns true if this instance represents a newer lock grantor version than
* <code>otherLockGrantorId</code>. Returns true if <code>otherLockGrantorId</code> is null.
*
* @param otherLockGrantorId the other lock grantor id to compare to
* @return true if this instance represents a newer lock grantor version
*/
public boolean isNewerThan(LockGrantorId otherLockGrantorId) {
if (otherLockGrantorId == null) {
return true;
}
boolean isNewer = this.lockGrantorVersion > otherLockGrantorId.getLockGrantorVersion();
if (!isNewer && this.lockGrantorMember.equals(otherLockGrantorId.getLockGrantorMember())) {
int otherGrantorSerialNumber = otherLockGrantorId.getLockGrantorSerialNumber();
boolean serialRolled =
this.lockGrantorSerialNumber > ROLLOVER_MARGIN && otherGrantorSerialNumber < 0;
isNewer = serialRolled || this.lockGrantorSerialNumber > otherGrantorSerialNumber;
}
return isNewer;
}
/**
* Returns true if this instance represents the same lock grantor member and version
*
* @param someLockGrantorMember the lock grantor member
* @param someLockGrantorVersion the lock grantor version
* @return true if <code>otherLockGrantorId</code> is same
*/
public boolean sameAs(InternalDistributedMember someLockGrantorMember,
long someLockGrantorVersion, int someLockGrantorSerialNumber) {
if (someLockGrantorMember == null) {
throw new IllegalStateException(
LocalizedStrings.LockGrantorId_SOMELOCKGRANTORID_MUST_NOT_BE_NULL.toLocalizedString());
}
return someLockGrantorMember.equals(this.lockGrantorMember)
&& someLockGrantorVersion == this.lockGrantorVersion
&& someLockGrantorSerialNumber == this.lockGrantorSerialNumber;
}
/**
* Returns true if this instance represents a local lock grantor.
*
* @return true if this instance represents a local lock grantor
*/
public boolean isLocal() {
return this.dm.getId().equals(this.lockGrantorMember);
}
/**
* Returns true if this instance represents a local lock grantor with the specified DLS serial
* number
*
* @return ture if local grantor with matching serial number
*/
public boolean isLocal(int dlsSerialNumber) {
return this.lockGrantorSerialNumber == dlsSerialNumber
&& this.dm.getId().equals(this.lockGrantorMember);
}
/**
* Returns true if this instance represents a remote lock grantor.
*
* @return true if this instance represents a remote lock grantor
*/
public boolean isRemote() {
return !this.dm.getId().equals(this.lockGrantorMember);
}
/**
* Returns a string representation of the object.
*
* @return a string representation of the object
*/
@Override
public String toString() {
final StringBuffer sb = new StringBuffer("[LockGrantorId: ");
sb.append("lockGrantorMember=").append(this.lockGrantorMember);
sb.append(", lockGrantorVersion=").append(this.lockGrantorVersion);
sb.append(", lockGrantorSerialNumber=").append(this.lockGrantorSerialNumber);
sb.append("]");
return sb.toString();
}
/**
* Indicates whether some other object is "equal to" this one.
*
* @param other the reference object with which to compare.
* @return true if this object is the same as the obj argument; false otherwise.
*/
@Override
public boolean equals(Object other) {
if (other == this)
return true;
if (other == null)
return false;
if (!(other instanceof LockGrantorId))
return false;
final LockGrantorId that = (LockGrantorId) other;
if (this.lockGrantorMember != that.lockGrantorMember && !(this.lockGrantorMember != null
&& this.lockGrantorMember.equals(that.lockGrantorMember)))
return false;
if (this.lockGrantorVersion != that.lockGrantorVersion)
return false;
if (this.lockGrantorSerialNumber != that.lockGrantorSerialNumber)
return false;
return true;
}
/**
* Returns a hash code for the object. This method is supported for the benefit of hashtables such
* as those provided by java.util.Hashtable.
*
* @return the integer 0 if description is null; otherwise a unique integer.
*/
@Override
public int hashCode() {
int result = 17;
final int mult = 37;
result =
mult * result + (this.lockGrantorMember == null ? 0 : this.lockGrantorMember.hashCode());
result = mult * result + (int) (this.lockGrantorVersion ^ (this.lockGrantorVersion >>> 32));
result = mult * result + this.lockGrantorSerialNumber;
return result;
}
}