ZonelessTime.java

/*
 * 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.eigenbase.util14;

import java.sql.Time;

import java.text.*;

import java.util.Calendar;
import java.util.TimeZone;

/**
 * ZonelessTime is a time value without a time zone.
 */
public class ZonelessTime extends ZonelessDatetime {
  //~ Static fields/initializers ---------------------------------------------

  /**
   * SerialVersionUID created with JDK 1.5 serialver tool.
   */
  private static final long serialVersionUID = 906156904798141861L;

  //~ Instance fields --------------------------------------------------------

  protected final int precision;
  protected transient Time tempTime;

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

  /**
   * Constructs a ZonelessTime
   */
  public ZonelessTime() {
    precision = 0;
  }

  /**
   * Constructs a ZonelessTime with precision.
   *
   * <p>The precision is the number of digits to the right of the decimal
   * point in the seconds value. For example, a <code>TIME(6)</code> has a
   * precision to microseconds.
   *
   * @param precision Number of digits of precision
   */
  public ZonelessTime(int precision) {
    this.precision = precision;
  }

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

  // override ZonelessDatetime
  public void setZonelessTime(long value) {
    super.setZonelessTime(value);
    clearDate();
  }

  // override ZonelessDatetime
  public void setZonedTime(long value, TimeZone zone) {
    super.setZonedTime(value, zone);
    clearDate();
  }

  // implement ZonelessDatetime
  public Object toJdbcObject() {
    return new Time(getJdbcTime(DateTimeUtil.DEFAULT_ZONE));
  }

  /**
   * Override ZonelessDatetime.
   *
   * <p>NOTE: the returned timestamp is based on the current date of the
   * specified time zone, rather than the context variable for current_date,
   * as specified by the SQL standard.
   */
  public long getJdbcTimestamp(TimeZone zone) {
    Calendar cal = getCalendar(DateTimeUtil.GMT_ZONE);
    cal.setTimeInMillis(getTime());
    int hour = cal.get(Calendar.HOUR_OF_DAY);
    int minute = cal.get(Calendar.MINUTE);
    int second = cal.get(Calendar.SECOND);
    int millis = cal.get(Calendar.MILLISECOND);

    cal.setTimeZone(zone);
    cal.setTimeInMillis(System.currentTimeMillis());
    cal.set(Calendar.HOUR_OF_DAY, hour);
    cal.set(Calendar.MINUTE, minute);
    cal.set(Calendar.SECOND, second);
    cal.set(Calendar.MILLISECOND, millis);
    return cal.getTimeInMillis();
  }

  /**
   * Converts this ZonelessTime to a java.sql.Time and formats it via the
   * {@link java.sql.Time#toString() toString()} method of that class.
   *
   * @return the formatted time string
   */
  public String toString() {
    Time jdbcTime = getTempTime(getJdbcTime(DateTimeUtil.DEFAULT_ZONE));
    return jdbcTime.toString();
  }

  /**
   * Formats this ZonelessTime via a SimpleDateFormat
   *
   * @param format format string, as required by SimpleDateFormat
   * @return the formatted time string
   */
  public String toString(String format) {
    DateFormat formatter = getFormatter(format);
    Time jdbcTime = getTempTime(getTime());
    return formatter.format(jdbcTime);
  }

  /**
   * Parses a string as a ZonelessTime.
   *
   * @param s a string representing a time in ISO format, i.e. according to
   *          the {@link SimpleDateFormat} string "HH:mm:ss"
   * @return the parsed time, or null if parsing failed
   */
  public static ZonelessTime parse(String s) {
    return parse(s, DateTimeUtil.TIME_FORMAT_STRING);
  }

  /**
   * Parses a string as a ZonelessTime using a given format string.
   *
   * @param s      a string representing a time the given format
   * @param format format string as per {@link SimpleDateFormat}
   * @return the parsed time, or null if parsing failed
   */
  public static ZonelessTime parse(String s, String format) {
    DateTimeUtil.PrecisionTime pt =
        DateTimeUtil.parsePrecisionDateTimeLiteral(
            s,
            format,
            DateTimeUtil.GMT_ZONE);
    if (pt == null) {
      return null;
    }
    ZonelessTime zt = new ZonelessTime(pt.getPrecision());
    zt.setZonelessTime(pt.getCalendar().getTime().getTime());
    return zt;
  }

  /**
   * Gets a temporary Time object. The same object is returned every time.
   */
  protected Time getTempTime(long value) {
    if (tempTime == null) {
      tempTime = new Time(value);
    } else {
      tempTime.setTime(value);
    }
    return tempTime;
  }
}

// End ZonelessTime.java