package org.infinispan.lucene;
import java.io.IOException;
import java.io.ObjectInput;
import java.io.ObjectOutput;
import java.util.Collections;
import java.util.Set;
import org.infinispan.commons.io.UnsignedNumeric;
import org.infinispan.commons.marshall.AbstractExternalizer;
/**
* Lucene's index segment files are chunked, for safe deletion of elements a read lock is
* implemented so that all chunks are deleted only after the usage counter is decremented to zero.
* FileReadLockKey is used as a key for the reference counters; a special purpose key was needed to
* make atomic operation possible.
*
* @author Sanne Grinovero
* @since 4.0
*/
public final class FileReadLockKey implements IndexScopedKey {
private final String indexName;
private final String fileName;
private final int hashCode;
private final int affinitySegmentId;
public FileReadLockKey(final String indexName, final String fileName, final int affinitySegmentId) {
if (indexName == null)
throw new IllegalArgumentException("indexName shall not be null");
if (fileName == null)
throw new IllegalArgumentException("fileName shall not be null");
this.indexName = indexName;
this.fileName = fileName;
this.affinitySegmentId = affinitySegmentId;
this.hashCode = generateHashCode();
}
/**
* Get the indexName.
*
* @return the indexName.
*/
@Override
public String getIndexName() {
return indexName;
}
@Override
public int getAffinitySegmentId() {
return affinitySegmentId;
}
/**
* Get the fileName.
*
* @return the fileName.
*/
public String getFileName() {
return fileName;
}
@Override
public Object accept(KeyVisitor visitor) throws Exception {
return visitor.visit(this);
}
@Override
public int hashCode() {
return hashCode;
}
private int generateHashCode() {
final int prime = 31;
int result = prime + fileName.hashCode();
return prime * result + indexName.hashCode();
}
@Override
public boolean equals(Object obj) {
if (this == obj)
return true;
if (obj == null)
return false;
if (FileReadLockKey.class != obj.getClass())
return false;
FileReadLockKey other = (FileReadLockKey) obj;
return fileName.equals(other.fileName) && indexName.equals(other.indexName);
}
@Override
public String toString() {
return "RL|" + fileName + "|"+ indexName + "|" + affinitySegmentId;
}
public static final class Externalizer extends AbstractExternalizer<FileReadLockKey> {
@Override
public void writeObject(final ObjectOutput output, final FileReadLockKey key) throws IOException {
output.writeUTF(key.indexName);
output.writeUTF(key.fileName);
UnsignedNumeric.writeUnsignedInt(output, key.affinitySegmentId);
}
@Override
public FileReadLockKey readObject(final ObjectInput input) throws IOException {
String indexName = input.readUTF();
String fileName = input.readUTF();
final int affinitySegmentId = UnsignedNumeric.readUnsignedInt(input);
return new FileReadLockKey(indexName, fileName, affinitySegmentId);
}
@Override
public Integer getId() {
return ExternalizerIds.FILE_READLOCK_KEY;
}
@Override
public Set<Class<? extends FileReadLockKey>> getTypeClasses() {
return Collections.singleton(FileReadLockKey.class);
}
}
}