SystemTime.java

/*******************************************************************************
 * Copyright (c) quickfixengine.org  All rights reserved. 
 * 
 * This file is part of the QuickFIX FIX Engine 
 * 
 * This file may be distributed under the terms of the quickfixengine.org 
 * license as defined by quickfixengine.org and appearing in the file 
 * LICENSE included in the packaging of this file. 
 * 
 * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING 
 * THE WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A 
 * PARTICULAR PURPOSE. 
 * 
 * See http://www.quickfixengine.org/LICENSE for licensing information. 
 * 
 * Contact ask@quickfixengine.org if any conditions of this licensing 
 * are not clear to you.
 ******************************************************************************/

package quickfix;

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

/**
 * A wrapper for the system time source, used primarily for unit testing.
 */
public class SystemTime {
    public static final TimeZone UTC_TIMEZONE = TimeZone.getTimeZone("UTC");

    private static SystemTimeSource DEFAULT_TIME_SOURCE = new SystemTimeSource() {
        public long getTime() {
            return System.currentTimeMillis();
        }
    };

    private static SystemTimeSource systemTimeSource = DEFAULT_TIME_SOURCE;

    public static synchronized long currentTimeMillis() {
        return systemTimeSource.getTime();
    }

    public static Date getDate() {
        return new Date(currentTimeMillis());
    }

    public static synchronized void setTimeSource(SystemTimeSource systemTimeSource) {
        SystemTime.systemTimeSource = systemTimeSource != null ? systemTimeSource
                : DEFAULT_TIME_SOURCE;
    }

    public static Calendar getUtcCalendar() {
        Calendar c = Calendar.getInstance(SystemTime.UTC_TIMEZONE);
        c.setTimeInMillis(currentTimeMillis());
        return c;
    }

    public static Calendar getUtcCalendar(Date date) {
        Calendar c = getUtcCalendar();
        c.setTime(date);
        return c;
    }

}