org.apache.james.transport.mailets.remote.delivery.Delay.java Source code

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Here is the source code for org.apache.james.transport.mailets.remote.delivery.Delay.java

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 * 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   *
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package org.apache.james.transport.mailets.remote.delivery;

import java.util.List;
import java.util.concurrent.TimeUnit;

import javax.mail.MessagingException;

import org.apache.james.util.TimeConverter;

import com.google.common.annotations.VisibleForTesting;
import com.google.common.base.MoreObjects;
import com.google.common.base.Objects;
import com.google.common.base.Splitter;
import com.google.common.base.Strings;

public class Delay {
    /**
     * <p> The optional attempt is the number of tries this delay should be used (default = 1).
     * The delayTime is parsed by {@link TimeConverter}</p>
     *
     * @param initString the string to initialize this Delay object from. It has the form "[attempt\*]delaytime[unit]"
     */
    public static Delay from(String initString) throws MessagingException {
        if (Strings.isNullOrEmpty(initString)) {
            throw new NumberFormatException("Null or Empty strings are not permitted");
        }
        List<String> parts = Splitter.on('*').trimResults().splitToList(initString);

        if (parts.size() == 1) {
            return new Delay(DEFAULT_ATTEMPTS, TimeConverter.getMilliSeconds(parts.get(0)));
        }
        if (parts.size() == 2) {
            int attempts = Integer.parseInt(parts.get(0));
            if (attempts < 0) {
                throw new MessagingException("Number of attempts negative in " + initString);
            }
            return new Delay(attempts, TimeConverter.getMilliSeconds(parts.get(1)));
        }
        throw new MessagingException(initString + " contains too much parts");
    }

    public static final long DEFAULT_DELAY_TIME = TimeUnit.HOURS.toMillis(6);
    public static final int DEFAULT_ATTEMPTS = 1;

    private final int attempts;
    private final long delayTimeInMs;

    public Delay() {
        this(DEFAULT_ATTEMPTS, DEFAULT_DELAY_TIME);
    }

    @VisibleForTesting
    Delay(int attempts, long delayTime) {
        this.attempts = attempts;
        this.delayTimeInMs = delayTime;
    }

    public long getDelayTimeInMs() {
        return delayTimeInMs;
    }

    public int getAttempts() {
        return attempts;
    }

    public List<Long> getExpendendDelays() {
        return Repeat.repeat(delayTimeInMs, attempts);
    }

    @Override
    public String toString() {
        return MoreObjects.toStringHelper(this).add("attempts", attempts).add("delayTime", delayTimeInMs)
                .toString();
    }

    @Override
    public boolean equals(Object o) {
        if (o instanceof Delay) {
            Delay that = (Delay) o;

            return Objects.equal(this.attempts, that.attempts)
                    && Objects.equal(this.delayTimeInMs, that.delayTimeInMs);
        }
        return false;
    }

    @Override
    public int hashCode() {
        return Objects.hashCode(attempts, delayTimeInMs);
    }
}