package org.infinispan.commands.write;
import org.infinispan.commands.Visitor;
import org.infinispan.commons.equivalence.Equivalence;
import org.infinispan.configuration.cache.Configuration;
import org.infinispan.container.entries.CacheEntry;
import org.infinispan.container.entries.MVCCEntry;
import org.infinispan.context.Flag;
import org.infinispan.context.InvocationContext;
import org.infinispan.lifecycle.ComponentStatus;
import org.infinispan.metadata.Metadata;
import org.infinispan.notifications.cachelistener.CacheNotifier;
import org.infinispan.util.logging.Log;
import org.infinispan.util.logging.LogFactory;
import java.util.Set;
/**
* @author Mircea.Markus@jboss.com
* @author <a href="mailto:galder.zamarreno@jboss.com">Galder Zamarreno</a>
* @since 4.0
*/
public class RemoveCommand extends AbstractDataWriteCommand {
private static final Log log = LogFactory.getLog(RemoveCommand.class);
public static final byte COMMAND_ID = 10;
protected CacheNotifier notifier;
boolean successful = true;
boolean nonExistent = false;
protected ValueMatcher valueMatcher;
private Equivalence valueEquivalence;
/**
* When not null, value indicates that the entry should only be removed if the key is mapped to this value.
* When null, the entry should
*/
protected Object value;
public RemoveCommand(Object key, Object value, CacheNotifier notifier, Set<Flag> flags, Equivalence valueEquivalence) {
super(key, flags);
this.value = value;
this.notifier = notifier;
this.valueEquivalence = valueEquivalence;
this.valueMatcher = value != null ? ValueMatcher.MATCH_EXPECTED : ValueMatcher.MATCH_ALWAYS;
}
public void init(CacheNotifier notifier, Configuration configuration) {
this.notifier = notifier;
this.valueEquivalence = configuration.dataContainer().valueEquivalence();
}
public RemoveCommand() {
}
@Override
public Object acceptVisitor(InvocationContext ctx, Visitor visitor) throws Throwable {
return visitor.visitRemoveCommand(ctx, this);
}
@Override
public Object perform(InvocationContext ctx) throws Throwable {
// It's not worth looking up the entry if we're never going to apply the change.
if (valueMatcher == ValueMatcher.MATCH_NEVER) {
successful = false;
return null;
}
MVCCEntry e = (MVCCEntry) ctx.lookupEntry(key);
if (e == null || e.isNull() || e.isRemoved()) {
nonExistent = true;
if (valueMatcher.matches(e, value, null, valueEquivalence)) {
if (e != null) {
e.setChanged(true);
e.setRemoved(true);
}
return isConditional() ? true : null;
} else {
log.trace("Nothing to remove since the entry doesn't exist in the context or it is null");
successful = false;
return false;
}
}
if (!valueMatcher.matches(e, value, null, valueEquivalence)) {
successful = false;
return false;
}
if (this instanceof EvictCommand) {
e.setEvicted(true);
}
return performRemove(e, ctx);
}
protected void notify(InvocationContext ctx, Object removedValue, Metadata removedMetadata) {
notifier.notifyCacheEntryRemoved(key, removedValue, removedMetadata, true, ctx, this);
}
@Override
public byte getCommandId() {
return COMMAND_ID;
}
@Override
public boolean equals(Object o) {
if (!super.equals(o)) {
return false;
}
RemoveCommand that = (RemoveCommand) o;
if (value != null ? !value.equals(that.value) : that.value != null) {
return false;
}
return true;
}
@Override
public int hashCode() {
int result = super.hashCode();
result = 31 * result + (value != null ? value.hashCode() : 0);
return result;
}
@Override
public String toString() {
return new StringBuilder()
.append("RemoveCommand{key=")
.append(key)
.append(", value=").append(value)
.append(", flags=").append(flags)
.append(", valueMatcher=").append(valueMatcher)
.append("}")
.toString();
}
@Override
public boolean isSuccessful() {
return successful;
}
@Override
public boolean isConditional() {
return value != null;
}
public boolean isNonExistent() {
return nonExistent;
}
@Override
@SuppressWarnings("unchecked")
public void setParameters(int commandId, Object[] parameters) {
if (commandId != COMMAND_ID) throw new IllegalStateException("Invalid method id");
key = parameters[0];
value = parameters[1];
flags = (Set<Flag>) parameters[2];
valueMatcher = (ValueMatcher) parameters[3];
}
@Override
public Object[] getParameters() {
return new Object[]{key, value, Flag.copyWithoutRemotableFlags(flags), valueMatcher};
}
@Override
public ValueMatcher getValueMatcher() {
return valueMatcher;
}
@Override
public void setValueMatcher(ValueMatcher valueMatcher) {
this.valueMatcher = valueMatcher;
}
@Override
public void updateStatusFromRemoteResponse(Object remoteResponse) {
// Remove without an expected value can't fail
if (value != null) {
successful = (Boolean) remoteResponse;
}
}
@Override
public boolean ignoreCommandOnStatus(ComponentStatus status) {
return false;
}
public Object getValue() {
return value;
}
public void setValue(Object value) {
this.value = value;
}
@Override
public final boolean isReturnValueExpected() {
//SKIP_RETURN_VALUE ignored for conditional remove
return super.isReturnValueExpected() || isConditional();
}
private Object performRemove(CacheEntry e, InvocationContext ctx) {
final Object removedValue = e.getValue();
notify(ctx, removedValue, e.getMetadata());
e.setRemoved(true);
e.setValid(false);
e.setChanged(true);
if (valueMatcher != ValueMatcher.MATCH_EXPECTED_OR_NEW) {
return isConditional() ? true : removedValue;
} else {
// Return the expected value when retrying
return isConditional() ? true : value;
}
}
}