ImmutablePositionSupport.java

package org.marketcetera.core.position;

import java.math.BigDecimal;
import java.util.Map;

import org.marketcetera.util.misc.ClassVersion;

import com.google.common.collect.ImmutableMap;

/* $License$ */

/**
 * An implementation of IncomingPositionSupport that provides positions from an fixed map.
 * 
 * @author <a href="mailto:will@marketcetera.com">Will Horn</a>
 * @version $Id: ImmutablePositionSupport.java 16154 2012-07-14 16:34:05Z colin $
 * @since 1.5.0
 */
@ClassVersion("$Id: ImmutablePositionSupport.java 16154 2012-07-14 16:34:05Z colin $")
public class ImmutablePositionSupport implements IncomingPositionSupport {

    private final ImmutableMap<? extends PositionKey<?>, BigDecimal> mPositions;

    /**
     * Constructor.
     * 
     * @param positions
     *            a map of positions, cannot be null, cannot have any null keys or values
     */
    public ImmutablePositionSupport(Map<? extends PositionKey<?>, BigDecimal> positions) {
        mPositions = ImmutableMap.copyOf(positions);
    }

    @Override
    public BigDecimal getIncomingPositionFor(PositionKey<?> key) {
        BigDecimal position = mPositions.get(key);
        return position != null ? position : BigDecimal.ZERO;
    }

    @Override
    public ImmutableMap<? extends PositionKey<?>, BigDecimal> getIncomingPositions() {
        return mPositions;
    }

}