// Copyright 2017 JanusGraph Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package org.janusgraph.diskstorage.indexing;
import com.google.common.base.Preconditions;
import com.google.common.collect.ImmutableList;
import org.janusgraph.graphdb.internal.Order;
import org.janusgraph.core.JanusGraphElement;
import org.janusgraph.graphdb.query.BackendQuery;
import org.janusgraph.graphdb.query.BaseQuery;
import org.janusgraph.graphdb.query.Query;
import org.janusgraph.graphdb.query.QueryUtil;
import org.janusgraph.graphdb.query.condition.Condition;
import org.apache.commons.lang.builder.HashCodeBuilder;
import java.util.List;
/**
* An external index query executed on an {@link IndexProvider}.
* <p/>
* A query is comprised of the store identifier against which the query ought to be executed and a query condition
* which defines which entries match the query.
*
* @author Matthias Broecheler (me@matthiasb.com)
*/
public class IndexQuery extends BaseQuery implements BackendQuery<IndexQuery> {
public static final ImmutableList<OrderEntry> NO_ORDER = ImmutableList.of();
private final String store;
private final Condition condition;
private final ImmutableList<OrderEntry> orders;
private final int hashcode;
public IndexQuery(String store, Condition condition, ImmutableList<OrderEntry> orders, int limit) {
super(limit);
Preconditions.checkNotNull(store);
Preconditions.checkNotNull(condition);
Preconditions.checkArgument(orders != null);
Preconditions.checkArgument(QueryUtil.isQueryNormalForm(condition));
this.condition = condition;
this.orders = orders;
this.store = store;
this.hashcode = new HashCodeBuilder().append(condition).append(store).append(orders).append(limit).toHashCode();
}
public IndexQuery(String store, Condition condition, ImmutableList<OrderEntry> orders) {
this(store, condition, orders, Query.NO_LIMIT);
}
public IndexQuery(String store, Condition condition) {
this(store, condition, NO_ORDER, Query.NO_LIMIT);
}
public IndexQuery(String store, Condition condition, int limit) {
this(store, condition, NO_ORDER, limit);
}
public Condition<JanusGraphElement> getCondition() {
return condition;
}
public List<OrderEntry> getOrder() {
return orders;
}
public String getStore() {
return store;
}
@Override
public IndexQuery setLimit(int limit) {
throw new UnsupportedOperationException();
}
@Override
public IndexQuery updateLimit(int newLimit) {
return new IndexQuery(store, condition, orders, newLimit);
}
@Override
public int hashCode() {
return hashcode;
}
@Override
public boolean equals(Object other) {
if (this == other) return true;
else if (other == null) return false;
else if (!getClass().isInstance(other)) return false;
IndexQuery oth = (IndexQuery) other;
return store.equals(oth.store) && orders.equals(oth.orders)
&& condition.equals(oth.condition) && getLimit() == oth.getLimit();
}
@Override
public String toString() {
StringBuilder b = new StringBuilder();
b.append("[").append(condition.toString()).append("]");
if (!orders.isEmpty()) b.append(orders);
if (hasLimit()) b.append("(").append(getLimit()).append(")");
b.append(":").append(store);
return b.toString();
}
public static class OrderEntry {
private final String key;
private final Order order;
private final Class<?> datatype;
public OrderEntry(String key, Order order, Class<?> datatype) {
Preconditions.checkNotNull(key);
Preconditions.checkNotNull(order);
Preconditions.checkNotNull(datatype);
this.key = key;
this.order = order;
this.datatype = datatype;
}
public String getKey() {
return key;
}
public Order getOrder() {
return order;
}
public Class<?> getDatatype() {
return datatype;
}
@Override
public int hashCode() {
return key.hashCode() * 4021 + order.hashCode();
}
@Override
public boolean equals(Object oth) {
if (this == oth) return true;
else if (oth == null) return false;
else if (!getClass().isInstance(oth)) return false;
OrderEntry o = (OrderEntry) oth;
return key.equals(o.key) && order == o.order;
}
@Override
public String toString() {
return order + "(" + key + ")";
}
}
}