org.eigenbase.rex.RexFieldCollation.java Source code

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Here is the source code for org.eigenbase.rex.RexFieldCollation.java

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/*
// Licensed to Julian Hyde under one or more contributor license
// agreements. See the NOTICE file distributed with this work for
// additional information regarding copyright ownership.
//
// Julian Hyde 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.eigenbase.rex;

import java.util.Set;

import org.eigenbase.rel.RelFieldCollation;
import org.eigenbase.sql.SqlKind;
import org.eigenbase.util.Pair;

import com.google.common.collect.ImmutableSet;

/**
 * Expression combined with sort flags (DESCENDING, NULLS LAST).
 */
public class RexFieldCollation extends Pair<RexNode, ImmutableSet<SqlKind>> {
    public RexFieldCollation(RexNode left, Set<SqlKind> right) {
        super(left, ImmutableSet.copyOf(right));
    }

    @Override
    public String toString() {
        String s = left.toString();
        for (SqlKind operator : right) {
            switch (operator) {
            case DESCENDING:
                s += " DESC";
                break;
            case NULLS_FIRST:
                s += " NULLS FIRST";
                break;
            case NULLS_LAST:
                s += " NULLS LAST";
                break;
            default:
                throw new AssertionError(operator);
            }
        }
        return s;
    }

    public RelFieldCollation.Direction getDirection() {
        return right.contains(SqlKind.DESCENDING) ? RelFieldCollation.Direction.DESCENDING
                : RelFieldCollation.Direction.ASCENDING;
    }

    public RelFieldCollation.NullDirection getNullDirection() {
        return right.contains(SqlKind.NULLS_LAST) ? RelFieldCollation.NullDirection.LAST
                : right.contains(SqlKind.NULLS_FIRST) ? RelFieldCollation.NullDirection.FIRST
                        : RelFieldCollation.NullDirection.UNSPECIFIED;
    }
}

// End RexFieldCollation.java