@Override
public boolean equals(Object o) {
if (o == this) return true;
if (!(o instanceof NodeValue)) return false;
NodeValue<?, ?> v = (NodeValue<?, ?>) o;
return getNodeId() == v.getNodeId()
&& Objects.equal(getKey(), v.getKey())
&& Objects.equal(getVersion(), v.getVersion());
}
/**
* Compute the repair set from the given values and nodes
*
* @param nodeValues The value found on each node
* @return A set of repairs to perform
*/
public List<NodeValue<K, V>> getRepairs(List<NodeValue<K, V>> nodeValues) {
int size = nodeValues.size();
if (size <= 1) return Collections.emptyList();
// A list of obsolete nodes that need to be repaired
Set<Integer> obsolete = new HashSet<Integer>(3);
// A Map of Version=>NodeValues that contains the current best estimate
// of the set of current versions
// and the nodes containing them
Multimap<Version, NodeValue<K, V>> concurrents = new HashMultimap<Version, NodeValue<K, V>>();
concurrents.put(nodeValues.get(0).getVersion(), nodeValues.get(0));
// check each value against the current set of most current versions
for (int i = 1; i < nodeValues.size(); i++) {
NodeValue<K, V> curr = nodeValues.get(i);
boolean concurrentToAll = true;
Set<Version> versions = new HashSet<Version>(concurrents.keySet());
for (Version concurrentVersion : versions) {
// if we already have the version, just add the nodevalue for
// future updating and move on
if (curr.getVersion().equals(concurrentVersion)) {
concurrents.put(curr.getVersion(), curr);
break;
}
// Check the ordering of the current value
Occured occured = curr.getVersion().compare(concurrentVersion);
if (occured == Occured.BEFORE) {
// This value is obsolete! Stop checking against other
// values...
obsolete.add(curr.getNodeId());
concurrentToAll = false;
break;
} else if (occured == Occured.AFTER) {
// This concurrent value is obsolete and the current value
// should replace it
for (NodeValue<K, V> v : concurrents.get(concurrentVersion)) obsolete.add(v.getNodeId());
concurrents.removeAll(concurrentVersion);
concurrentToAll = false;
concurrents.put(curr.getVersion(), curr);
}
}
// if the value is concurrent to all existing versions then add it
// to the concurrent set
if (concurrentToAll) concurrents.put(curr.getVersion(), curr);
}
// Construct the list of repairs
List<NodeValue<K, V>> repairs = new ArrayList<NodeValue<K, V>>(3);
for (Integer id : obsolete) {
// repair all obsolete nodes
for (Version v : concurrents.keySet()) {
NodeValue<K, V> concurrent = concurrents.get(v).iterator().next();
NodeValue<K, V> repair =
new NodeValue<K, V>(id, concurrent.getKey(), concurrent.getVersioned());
repairs.add(repair);
}
}
if (concurrents.size() > 1) {
// if there are more then one concurrent versions on different
// nodes,
// we should repair so all have the same set of values
Set<NodeValue<K, V>> existing = new HashSet<NodeValue<K, V>>(repairs);
for (NodeValue<K, V> entry1 : concurrents.values()) {
for (NodeValue<K, V> entry2 : concurrents.values()) {
if (!entry1.getVersion().equals(entry2.getVersion())) {
NodeValue<K, V> repair =
new NodeValue<K, V>(entry1.getNodeId(), entry2.getKey(), entry2.getVersioned());
if (!existing.contains(repair)) repairs.add(repair);
}
}
}
}
return repairs;
}
