/*
* JBoss, Home of Professional Open Source
* Copyright 2009 Red Hat Inc. and/or its affiliates and other
* contributors as indicated by the @author tags. All rights reserved.
* See the copyright.txt in the distribution for a full listing of
* individual contributors.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.infinispan.commands.remote;
import org.infinispan.commands.CommandsFactory;
import org.infinispan.commands.FlagAffectedCommand;
import org.infinispan.commands.control.LockControlCommand;
import org.infinispan.commands.read.GetKeyValueCommand;
import org.infinispan.container.InternalEntryFactory;
import org.infinispan.container.entries.CacheEntry;
import org.infinispan.container.entries.InternalCacheEntry;
import org.infinispan.container.entries.InternalCacheValue;
import org.infinispan.container.entries.MVCCEntry;
import org.infinispan.context.Flag;
import org.infinispan.context.InvocationContext;
import org.infinispan.context.InvocationContextContainer;
import org.infinispan.distribution.DistributionManager;
import org.infinispan.interceptors.InterceptorChain;
import org.infinispan.reconfigurableprotocol.manager.ReconfigurableReplicationManager;
import org.infinispan.transaction.TransactionTable;
import org.infinispan.transaction.xa.GlobalTransaction;
import org.infinispan.util.logging.Log;
import org.infinispan.util.logging.LogFactory;
import java.util.Collections;
import java.util.EnumSet;
import java.util.Set;
/**
* Issues a remote get call. This is not a {@link org.infinispan.commands.VisitableCommand} and hence not passed up the
* {@link org.infinispan.interceptors.base.CommandInterceptor} chain.
* <p/>
*
* @author Mircea.Markus@jboss.com
* @since 4.0
*/
public class ClusteredGetCommand extends BaseRpcCommand implements FlagAffectedCommand {
public static final byte COMMAND_ID = 16;
private static final Log log = LogFactory.getLog(ClusteredGetCommand.class);
private static final boolean trace = log.isTraceEnabled();
private Object key;
private InvocationContextContainer icc;
private CommandsFactory commandsFactory;
private InterceptorChain invoker;
private boolean acquireRemoteLock;
private GlobalTransaction gtx;
private Set<Flag> flags;
private DistributionManager distributionManager;
private TransactionTable txTable;
private InternalEntryFactory entryFactory;
private ReconfigurableReplicationManager manager;
private ClusteredGetCommand() {
super(null); // For command id uniqueness test
}
public ClusteredGetCommand(String cacheName) {
super(cacheName);
}
public ClusteredGetCommand(Object key, String cacheName, Set<Flag> flags, boolean acquireRemoteLock, GlobalTransaction gtx) {
super(cacheName);
this.key = key;
this.flags = flags;
this.acquireRemoteLock = acquireRemoteLock;
this.gtx = gtx;
if (acquireRemoteLock && (gtx == null))
throw new IllegalArgumentException("Cannot have null tx if we need to acquire locks");
}
public ClusteredGetCommand(Object key, String cacheName) {
this(key, cacheName, Collections.<Flag>emptySet(), false, null);
}
public ClusteredGetCommand(String key, String cacheName, Set<Flag> flags) {
this(key, cacheName, flags, false, null);
}
public void initialize(InvocationContextContainer icc, CommandsFactory commandsFactory, InternalEntryFactory entryFactory,
InterceptorChain interceptorChain, DistributionManager distributionManager, TransactionTable txTable,
ReconfigurableReplicationManager manager) {
this.distributionManager = distributionManager;
this.icc = icc;
this.commandsFactory = commandsFactory;
this.invoker = interceptorChain;
this.txTable = txTable;
this.entryFactory = entryFactory;
this.manager = manager;
this.manager.initGlobalTransactionIfNeeded(gtx);
}
/**
* Invokes a logical "get(key)" on a remote cache and returns results.
*
* @param context invocation context, ignored.
* @return returns an <code>CacheEntry</code> or null, if no entry is found.
*/
@Override
public Object perform(InvocationContext context) throws Throwable {
acquireLocksIfNeeded();
if (distributionManager != null && distributionManager.isAffectedByRehash(key)) return null;
// make sure the get command doesn't perform a remote call
// as our caller is already calling the ClusteredGetCommand on all the relevant nodes
Set<Flag> commandFlags = EnumSet.of(Flag.SKIP_REMOTE_LOOKUP);
if (this.flags != null) commandFlags.addAll(this.flags);
GetKeyValueCommand command = constructCommand(commandFlags);
return invoke(command, createInvocationContext(command));
}
protected InternalCacheValue invoke(GetKeyValueCommand command, InvocationContext context) {
CacheEntry cacheEntry = (CacheEntry) invoker.invoke(context, command);
if (cacheEntry == null) {
if (trace) log.trace("Did not find anything, returning null");
return null;
}
//this might happen if the value was fetched from a cache loader
if (cacheEntry instanceof MVCCEntry) {
if (trace) log.trace("Handling an internal cache entry...");
MVCCEntry mvccEntry = (MVCCEntry) cacheEntry;
return entryFactory.createValue(mvccEntry);
} else {
InternalCacheEntry internalCacheEntry = (InternalCacheEntry) cacheEntry;
return internalCacheEntry.toInternalCacheValue();
}
}
protected GetKeyValueCommand constructCommand(Set<Flag> flags) {
GetKeyValueCommand command = commandsFactory.buildGetKeyValueCommand(key, flags);
command.setReturnCacheEntry(true);
return command;
}
protected InvocationContext createInvocationContext(GetKeyValueCommand command) {
return icc.createRemoteInvocationContextForCommand(command, getOrigin());
}
private void acquireLocksIfNeeded() throws Throwable {
if (acquireRemoteLock) {
LockControlCommand lockControlCommand = commandsFactory.buildLockControlCommand(key, flags, gtx);
lockControlCommand.init(invoker, icc, txTable, null, manager);
lockControlCommand.perform(null);
}
}
@Override
public byte getCommandId() {
return COMMAND_ID;
}
@Override
public Object[] getParameters() {
return new Object[]{key, flags, acquireRemoteLock, gtx};
}
@Override
public void setParameters(int commandId, Object[] args) {
int i = 0;
key = args[i++];
flags = (Set<Flag>) args[i++];
acquireRemoteLock = (Boolean) args[i++];
gtx = (GlobalTransaction) args[i];
}
@Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
ClusteredGetCommand that = (ClusteredGetCommand) o;
return !(key != null ? !key.equals(that.key) : that.key != null);
}
@Override
public int hashCode() {
int result;
result = (key != null ? key.hashCode() : 0);
return result;
}
@Override
public String toString() {
return new StringBuilder()
.append("ClusteredGetCommand{key=")
.append(key)
.append(", flags=").append(flags)
.append("}")
.toString();
}
public Object getKey() {
return key;
}
@Override
public Set<Flag> getFlags() {
return flags;
}
@Override
public void setFlags(Set<Flag> flags) {
this.flags = flags;
}
@Override
public boolean hasFlag(Flag flag) {
return flags != null && flags.contains(flag);
}
@Override
public boolean isReturnValueExpected() {
return true;
}
}