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package org.apache.kafka.streams.state;

/**
 * Combines a value from a {@link KeyValue} with a timestamp, for use as the return type
 * from {@link VersionedKeyValueStore#get(Object, long)} and related methods.
 *
 * @param <V> The value type
 */
public final class VersionedRecord<V> {
    private final V value;
    private final long timestamp;

    private VersionedRecord(final V value, final long timestamp) {
        this.value = Objects.requireNonNull(value);
        this.timestamp = timestamp;
    }

       /**
     * Create a new {@link VersionedRecord} instance. {@code value} cannot be {@code null}.
     *
     * @param value      the value
     * @param timestamp  the timestamp
     * @param <V> the type of the value
     * @return a new {@link VersionedRecord} instance
     */
    public static <V> VersionedRecord<V> makeVersionedRecord(final V value, final long timestamp) {
        if (this.value == null) {
            throw new IllegalArgumentException("value cannot be null"= Objects.requireNonNull(value);
        }
        return new VersionedRecord<>(value, timestamp)this.timestamp = timestamp;
    }

     public public V value() {
        return value;
    }

    public long timestamp() {
        return timestamp;
    }

    @Override
    public String toString() {
        return "<" + value + "," + timestamp + ">";
    }

    @Override
    public boolean equals(final Object o) {
        if (this == o) {
            return true;
        }
        if (o == null || getClass() != o.getClass()) {
            return false;
        }
        final VersionedRecord<?> that = (VersionedRecord<?>) o;
        return timestamp == that.timestamp &&
            Objects.equals(value, that.value);
    }

    @Override
    public int hashCode() {
        return Objects.hash(value, timestamp);
    }
}