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//
// Burton Computer Corporation
// http://www.burton-computer.com
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// Copyright (c) 2017, Burton Computer Corporation
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package org.javimmutable.collections;

import javax.annotation.Nonnull;
import javax.annotation.concurrent.Immutable;
import java.util.Objects;

/**
 * Container object holding two Cursors.  The two Cursors visit different
 * elements from the same original Cursor.  The left Cursor always visits elements
 * that would that come before the elements visited by the right Cursor in the
 * original Cursor.  Visiting all elements in the left Cursor and then visiting
 * all elements in the right Cursor yields exactly the same elements as visiting
 * all elements from the original Cursor.
 */
@Immutable
public class SplitCursor
{
    private final Cursor left;
    private final Cursor right;

    public SplitCursor(@Nonnull Cursor left,
                       @Nonnull Cursor right)
    {
        this.left = left;
        this.right = right;
    }

    @Nonnull
    public Cursor getLeft()
    {
        return left;
    }

    @Nonnull
    public Cursor getRight()
    {
        return right;
    }

    @Override
    public boolean equals(Object o)
    {
        if (this == o) {
            return true;
        }
        if (o == null || getClass() != o.getClass()) {
            return false;
        }
        SplitCursor that = (SplitCursor)o;
        return Objects.equals(left, that.left) &&
               Objects.equals(right, that.right);
    }

    @Override
    public int hashCode()
    {
        return Objects.hash(left, right);
    }
}