com.facebook.presto.teradata.functions.dateformat.DateFormatParser.java Source code

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Here is the source code for com.facebook.presto.teradata.functions.dateformat.DateFormatParser.java

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/*
 * 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 com.facebook.presto.teradata.functions.dateformat;

import com.facebook.presto.spi.PrestoException;
import com.facebook.presto.spi.StandardErrorCode;
import com.facebook.presto.teradata.functions.DateFormat;
import org.antlr.v4.runtime.ANTLRInputStream;
import org.antlr.v4.runtime.Token;
import org.joda.time.format.DateTimeFormatter;
import org.joda.time.format.DateTimeFormatterBuilder;

import java.util.List;

import static com.facebook.presto.spi.StandardErrorCode.INVALID_FUNCTION_ARGUMENT;

public class DateFormatParser {
    private DateFormatParser() {
    }

    public static DateTimeFormatter createDateTimeFormatter(String format) {
        DateTimeFormatterBuilder builder = new DateTimeFormatterBuilder();
        for (Token token : tokenize(format)) {
            switch (token.getType()) {
            case DateFormat.TEXT:
                builder.appendLiteral(token.getText());
                break;
            case DateFormat.DD:
                builder.appendDayOfMonth(2);
                break;
            case DateFormat.HH24:
                builder.appendHourOfDay(2);
                break;
            case DateFormat.HH:
                builder.appendHourOfHalfday(2);
                break;
            case DateFormat.MI:
                builder.appendMinuteOfHour(2);
                break;
            case DateFormat.MM:
                builder.appendMonthOfYear(2);
                break;
            case DateFormat.SS:
                builder.appendSecondOfMinute(2);
                break;
            case DateFormat.YY:
                builder.appendTwoDigitYear(2050);
                break;
            case DateFormat.YYYY:
                builder.appendYear(4, 4);
                break;
            case DateFormat.UNRECOGNIZED:
            default:
                throw new PrestoException(StandardErrorCode.INVALID_FUNCTION_ARGUMENT,
                        String.format("Failed to tokenize string [%s] at offset [%d]", token.getText(),
                                token.getCharPositionInLine()));
            }
        }

        try {
            return builder.toFormatter();
        } catch (UnsupportedOperationException e) {
            throw new PrestoException(INVALID_FUNCTION_ARGUMENT, e);
        }
    }

    public static List<? extends Token> tokenize(String format) {
        DateFormat lexer = new com.facebook.presto.teradata.functions.DateFormat(new ANTLRInputStream(format));
        return lexer.getAllTokens();
    }
}