package org.infinispan.commands.tx;
import org.infinispan.commands.Visitor;
import org.infinispan.commands.write.ApplyDeltaCommand;
import org.infinispan.commands.write.ClearCommand;
import org.infinispan.commands.write.DataWriteCommand;
import org.infinispan.commands.write.PutKeyValueCommand;
import org.infinispan.commands.write.PutMapCommand;
import org.infinispan.commands.write.RemoveCommand;
import org.infinispan.commands.write.ReplaceCommand;
import org.infinispan.commands.write.WriteCommand;
import org.infinispan.commons.hash.Hash;
import org.infinispan.commons.hash.MurmurHash3;
import org.infinispan.commons.util.InfinispanCollections;
import org.infinispan.context.InvocationContext;
import org.infinispan.context.impl.RemoteTxInvocationContext;
import org.infinispan.context.impl.TxInvocationContext;
import org.infinispan.notifications.cachelistener.CacheNotifier;
import org.infinispan.transaction.impl.RemoteTransaction;
import org.infinispan.transaction.xa.GlobalTransaction;
import org.infinispan.transaction.xa.recovery.RecoveryManager;
import org.infinispan.util.logging.Log;
import org.infinispan.util.logging.LogFactory;
import java.util.Arrays;
import java.util.Comparator;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
/**
* Command corresponding to the 1st phase of 2PC.
*
* @author Manik Surtani (<a href="mailto:manik@jboss.org">manik@jboss.org</a>)
* @author Mircea.Markus@jboss.com
* @since 4.0
*/
public class PrepareCommand extends AbstractTransactionBoundaryCommand {
private static final Log log = LogFactory.getLog(PrepareCommand.class);
private boolean trace = log.isTraceEnabled();
public static final byte COMMAND_ID = 12;
protected WriteCommand[] modifications;
protected boolean onePhaseCommit;
protected CacheNotifier notifier;
protected RecoveryManager recoveryManager;
private transient boolean replayEntryWrapping = false;
private static final WriteCommand[] EMPTY_WRITE_COMMAND_ARRAY = new WriteCommand[0];
private static final Object[] EMPTY_ARRAY = new Object[0];
private static final Comparator<Object> KEY_COMPARATOR = new Comparator<Object>() {
private final Hash hash = new MurmurHash3();
@Override
public int compare(Object o1, Object o2) {
return Integer.valueOf(hash.hash(o1)).compareTo(hash.hash(o2));
}
};
public void initialize(CacheNotifier notifier, RecoveryManager recoveryManager) {
this.notifier = notifier;
this.recoveryManager = recoveryManager;
}
private PrepareCommand() {
super(null); // For command id uniqueness test
}
public PrepareCommand(String cacheName, GlobalTransaction gtx, boolean onePhaseCommit, WriteCommand... modifications) {
super(cacheName);
this.globalTx = gtx;
this.modifications = modifications;
this.onePhaseCommit = onePhaseCommit;
}
public PrepareCommand(String cacheName, GlobalTransaction gtx, List<WriteCommand> commands, boolean onePhaseCommit) {
super(cacheName);
this.globalTx = gtx;
this.modifications = commands == null || commands.isEmpty() ? null : commands.toArray(new WriteCommand[commands.size()]);
this.onePhaseCommit = onePhaseCommit;
}
public PrepareCommand(String cacheName) {
super(cacheName);
}
@Override
public Object perform(InvocationContext ignored) throws Throwable {
if (ignored != null)
throw new IllegalStateException("Expected null context!");
if (recoveryManager != null && recoveryManager.isTransactionPrepared(globalTx)) {
log.tracef("The transaction %s is already prepared. Skipping prepare call.", globalTx);
return null;
}
// 1. first create a remote transaction (or get the existing one)
RemoteTransaction remoteTransaction = getRemoteTransaction();
//set the list of modifications anyway, as the transaction might have already been created by a previous
//LockControlCommand with null modifications.
if (hasModifications()) {
remoteTransaction.setModifications(Arrays.asList(modifications));
}
// 2. then set it on the invocation context
RemoteTxInvocationContext ctx = icf.createRemoteTxInvocationContext(remoteTransaction, getOrigin());
if (trace)
log.tracef("Invoking remotely originated prepare: %s with invocation context: %s", this, ctx);
notifier.notifyTransactionRegistered(ctx.getGlobalTransaction(), false);
return invoker.invoke(ctx, this);
}
@Override
protected RemoteTransaction getRemoteTransaction() {
return txTable.getOrCreateRemoteTransaction(globalTx, modifications);
}
@Override
public Object acceptVisitor(InvocationContext ctx, Visitor visitor) throws Throwable {
return visitor.visitPrepareCommand((TxInvocationContext) ctx, this);
}
public WriteCommand[] getModifications() {
return modifications == null ? EMPTY_WRITE_COMMAND_ARRAY : modifications;
}
public boolean isOnePhaseCommit() {
return onePhaseCommit;
}
@Override
public byte getCommandId() {
return COMMAND_ID;
}
@Override
public Object[] getParameters() {
int numMods = modifications == null ? 0 : modifications.length;
int i = 0;
final int params = 3;
Object[] retval = new Object[numMods + params];
retval[i++] = globalTx;
retval[i++] = onePhaseCommit;
retval[i++] = numMods;
if (numMods > 0) System.arraycopy(modifications, 0, retval, params, numMods);
return retval;
}
@Override
@SuppressWarnings("unchecked")
public void setParameters(int commandId, Object[] args) {
int i = 0;
globalTx = (GlobalTransaction) args[i++];
onePhaseCommit = (Boolean) args[i++];
int numMods = (Integer) args[i++];
if (numMods > 0) {
modifications = new WriteCommand[numMods];
System.arraycopy(args, i, modifications, 0, numMods);
}
}
public PrepareCommand copy() {
PrepareCommand copy = new PrepareCommand(cacheName);
copy.globalTx = globalTx;
copy.modifications = modifications == null ? null : modifications.clone();
copy.onePhaseCommit = onePhaseCommit;
return copy;
}
@Override
public String toString() {
return "PrepareCommand {" +
"modifications=" + (modifications == null ? null : Arrays.asList(modifications)) +
", onePhaseCommit=" + onePhaseCommit +
", " + super.toString();
}
public boolean hasModifications() {
return modifications != null && modifications.length > 0;
}
public Set<Object> getAffectedKeys() {
if (modifications == null || modifications.length == 0)
return InfinispanCollections.emptySet();
if (modifications.length == 1) return modifications[0].getAffectedKeys();
Set<Object> keys = new HashSet<Object>(modifications.length);
for (WriteCommand wc: modifications) keys.addAll(wc.getAffectedKeys());
return keys;
}
/**
* If set to true, then the keys touched by this transaction are to be wrapped again and original ones discarded.
*/
public boolean isReplayEntryWrapping() {
return replayEntryWrapping;
}
/**
* @see #isReplayEntryWrapping()
*/
public void setReplayEntryWrapping(boolean replayEntryWrapping) {
this.replayEntryWrapping = replayEntryWrapping;
}
public boolean writesToASingleKey() {
if (modifications == null || modifications.length != 1)
return false;
WriteCommand wc = modifications[0];
return wc instanceof PutKeyValueCommand || wc instanceof RemoveCommand || wc instanceof ReplaceCommand;
}
@Override
public boolean isReturnValueExpected() {
return false;
}
/**
* It returns an array of keys affected by the WriteCommand in modifications.
*
* @param sort if {@code true}, the array returned is sorted by the key hash.
* @return an array of keys
*/
public Object[] getAffectedKeysToLock(boolean sort) {
if (modifications == null) {
return EMPTY_ARRAY;
}
Set<Object> set = new HashSet<Object>(modifications.length);
for (WriteCommand wc : modifications) {
switch (wc.getCommandId()) {
case ClearCommand.COMMAND_ID:
return null;
case PutKeyValueCommand.COMMAND_ID:
case RemoveCommand.COMMAND_ID:
case ReplaceCommand.COMMAND_ID:
set.add(((DataWriteCommand) wc).getKey());
break;
case PutMapCommand.COMMAND_ID:
set.addAll(wc.getAffectedKeys());
break;
case ApplyDeltaCommand.COMMAND_ID:
ApplyDeltaCommand command = (ApplyDeltaCommand) wc;
Object[] compositeKeys = command.getCompositeKeys();
set.addAll(Arrays.asList(compositeKeys));
break;
}
}
Object[] sorted = set.toArray(new Object[set.size()]);
if (sort) {
Arrays.sort(sorted, KEY_COMPARATOR);
}
return sorted;
}
}