org.apache.calcite.sql.util.ChainedSqlOperatorTable.java Source code

Introduction

Here is the source code for org.apache.calcite.sql.util.ChainedSqlOperatorTable.java

Source

/*
 * 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.calcite.sql.util;

import org.apache.calcite.sql.SqlFunctionCategory;
import org.apache.calcite.sql.SqlIdentifier;
import org.apache.calcite.sql.SqlOperator;
import org.apache.calcite.sql.SqlOperatorTable;
import org.apache.calcite.sql.SqlSyntax;

import com.google.common.collect.ImmutableList;

import java.util.ArrayList;
import java.util.List;

/**
 * ChainedSqlOperatorTable implements the {@link SqlOperatorTable} interface by
 * chaining together any number of underlying operator table instances.
 */
public class ChainedSqlOperatorTable implements SqlOperatorTable {
    //~ Instance fields --------------------------------------------------------

    protected final List<SqlOperatorTable> tableList;

    //~ Constructors -----------------------------------------------------------

    /**
     * Creates a table based on a given list.
     */
    public ChainedSqlOperatorTable(List<SqlOperatorTable> tableList) {
        this.tableList = ImmutableList.copyOf(tableList);
    }

    /** Creates a {@code ChainedSqlOperatorTable}. */
    public static SqlOperatorTable of(SqlOperatorTable... tables) {
        return new ChainedSqlOperatorTable(ImmutableList.copyOf(tables));
    }

    //~ Methods ----------------------------------------------------------------

    /**
     * Adds an underlying table. The order in which tables are added is
     * significant; tables added earlier have higher lookup precedence. A table
     * is not added if it is already on the list.
     *
     * @param table table to add
     */
    public void add(SqlOperatorTable table) {
        if (!tableList.contains(table)) {
            tableList.add(table);
        }
    }

    public void lookupOperatorOverloads(SqlIdentifier opName, SqlFunctionCategory category, SqlSyntax syntax,
            List<SqlOperator> operatorList) {
        for (SqlOperatorTable table : tableList) {
            table.lookupOperatorOverloads(opName, category, syntax, operatorList);
        }
    }

    public List<SqlOperator> getOperatorList() {
        List<SqlOperator> list = new ArrayList<>();
        for (SqlOperatorTable table : tableList) {
            list.addAll(table.getOperatorList());
        }
        return list;
    }
}

// End ChainedSqlOperatorTable.java