org.apache.drill.exec.planner.sql.parser.DrillCompoundIdentifier.java Source code

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Here is the source code for org.apache.drill.exec.planner.sql.parser.DrillCompoundIdentifier.java

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/**
 * 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.exec.planner.sql.parser;

import java.util.Collections;
import java.util.List;

import org.apache.calcite.sql.SqlBasicCall;
import org.apache.calcite.sql.SqlIdentifier;
import org.apache.calcite.sql.SqlLiteral;
import org.apache.calcite.sql.SqlNode;
import org.apache.calcite.sql.fun.SqlStdOperatorTable;
import org.apache.calcite.sql.parser.SqlParserPos;

import com.google.common.collect.ImmutableList;
import com.google.common.collect.Lists;

public class DrillCompoundIdentifier extends SqlIdentifier {

    List<IdentifierHolder> ids;

    private static List<String> getNames(List<IdentifierHolder> identifiers) {
        List<String> names = Lists.newArrayListWithCapacity(identifiers.size());
        for (IdentifierHolder h : identifiers) {
            names.add(h.value);
        }
        return names;
    }

    public DrillCompoundIdentifier(List<IdentifierHolder> identifiers) {
        super(getNames(identifiers), identifiers.get(0).parserPos);
        this.ids = identifiers;
    }

    static final org.slf4j.Logger logger = org.slf4j.LoggerFactory.getLogger(DrillCompoundIdentifier.class);

    public static Builder newBuilder() {
        return new Builder();
    }

    public static class Builder {
        private List<IdentifierHolder> identifiers = Lists.newArrayList();

        public DrillCompoundIdentifier build() {
            return new DrillCompoundIdentifier(identifiers);
        }

        public void addString(String name, SqlParserPos pos) {
            identifiers.add(new IdentifierHolder(name, pos, false));
        }

        public void addIndex(int index, SqlParserPos pos) {
            identifiers.add(new IdentifierHolder(Integer.toString(index), pos, true));
        }
    }

    public SqlNode getAsSqlNode() {
        if (ids.size() == 1) {
            return new SqlIdentifier(Collections.singletonList(ids.get(0).value), ids.get(0).parserPos);
        }

        int startIndex;
        SqlNode node;

        if (ids.get(1).isArray()) {
            // handle everything post zero index as item operator.
            startIndex = 1;
            node = new SqlIdentifier( //
                    ImmutableList.of(ids.get(0).value), //
                    null, //
                    ids.get(0).parserPos, //
                    ImmutableList.of(ids.get(0).parserPos));
        } else {
            // handle everything post two index as item operator.
            startIndex = 2;
            node = new SqlIdentifier( //
                    ImmutableList.of(ids.get(0).value, ids.get(1).value), //
                    null, //
                    ids.get(0).parserPos, //
                    ImmutableList.of(ids.get(0).parserPos, ids.get(1).parserPos));

        }
        for (int i = startIndex; i < ids.size(); i++) {
            node = ids.get(i).getNode(node);
        }

        return node;
    }

    public SqlNode getAsCompoundIdentifier() {
        List<String> names = Lists.newArrayListWithCapacity(ids.size());
        List<SqlParserPos> pos = Lists.newArrayListWithCapacity(ids.size());
        for (int i = 0; i < ids.size(); i++) {
            IdentifierHolder holder = ids.get(i);
            names.add(holder.value);
            pos.add(holder.parserPos);
        }
        return new SqlIdentifier(names, null, pos.get(0), pos);
    }

    private static class IdentifierHolder {
        String value;
        SqlParserPos parserPos;
        boolean isArray;

        public IdentifierHolder(String value, SqlParserPos parserPos, boolean isArray) {
            super();
            this.isArray = isArray;
            this.value = value;
            this.parserPos = parserPos;
        }

        public boolean isArray() {
            return isArray;
        }

        public SqlNode getNode(SqlNode node) {
            SqlLiteral literal;
            if (isArray) {
                literal = SqlLiteral.createExactNumeric(value, parserPos);
            } else {
                literal = SqlLiteral.createCharString(value, parserPos);
            }
            return new SqlBasicCall(SqlStdOperatorTable.ITEM, new SqlNode[] { node, literal }, parserPos);
        }

    }
}