| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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.apache.drill.common.logical.data; |
| |
| import com.google.common.collect.Iterators; |
| import com.google.common.collect.Lists; |
| import org.apache.drill.common.expression.FieldReference; |
| |
| import com.fasterxml.jackson.annotation.JsonCreator; |
| import com.fasterxml.jackson.annotation.JsonProperty; |
| import com.fasterxml.jackson.annotation.JsonTypeName; |
| import org.apache.drill.common.expression.LogicalExpression; |
| import org.apache.drill.common.logical.data.visitors.LogicalVisitor; |
| |
| import java.util.Iterator; |
| import java.util.List; |
| |
| import static com.google.common.base.Preconditions.checkState; |
| |
| @JsonTypeName("window") |
| public class Window extends SingleInputOperator { |
| private final List<NamedExpression> withins; |
| private final List<NamedExpression> aggregations; |
| private final List<Order.Ordering> orderings; |
| private final long start; |
| private final long end; |
| |
| |
| @JsonCreator |
| public Window(@JsonProperty("withins") List<NamedExpression> withins, |
| @JsonProperty("aggregations") List<NamedExpression> aggregations, |
| @JsonProperty("orderings") List<Order.Ordering> orderings, |
| @JsonProperty("start") Long start, |
| @JsonProperty("end") Long end) { |
| super(); |
| this.withins = withins; |
| this.start = start == null ? Long.MIN_VALUE : start; |
| this.end = end == null ? Long.MIN_VALUE : end; |
| this.aggregations = aggregations; |
| this.orderings = orderings; |
| } |
| |
| public List<NamedExpression> getWithins() { |
| return withins; |
| } |
| |
| public long getStart() { |
| return start; |
| } |
| |
| public long getEnd() { |
| return end; |
| } |
| |
| public List<NamedExpression> getAggregations() { |
| return aggregations; |
| } |
| |
| public List<Order.Ordering> getOrderings() { |
| return orderings; |
| } |
| |
| @Override |
| public <T, X, E extends Throwable> T accept(LogicalVisitor<T, X, E> logicalVisitor, X value) throws E { |
| return logicalVisitor.visitWindow(this, value); |
| } |
| |
| @Override |
| public Iterator<LogicalOperator> iterator() { |
| return Iterators.singletonIterator(getInput()); |
| } |
| |
| public static class Builder extends AbstractSingleBuilder<Window, Builder>{ |
| private List<NamedExpression> aggregations = Lists.newArrayList(); |
| private List<NamedExpression> withins = Lists.newArrayList(); |
| private List<Order.Ordering> orderings = Lists.newArrayList(); |
| private long start = Long.MIN_VALUE; |
| private long end = Long.MIN_VALUE; |
| |
| |
| public Builder addAggregation(FieldReference ref, LogicalExpression expr){ |
| aggregations.add(new NamedExpression(expr, ref)); |
| return this; |
| } |
| |
| public Builder addWithin(FieldReference within, LogicalExpression expr) { |
| withins.add(new NamedExpression(expr, within)); |
| return this; |
| } |
| |
| public Window internalBuild() { |
| //TODO withins can actually be empty: over(), over(order by <expression>), ... |
| checkState(!withins.isEmpty(), "Withins in window must not be empty."); |
| checkState(!aggregations.isEmpty(), "Aggregations in window must not be empty."); |
| return new Window(withins, aggregations, orderings, start, end); |
| } |
| |
| public Builder addOrdering(Order.Ordering ordering) { |
| orderings.add(ordering); |
| return this; |
| } |
| } |
| } |