core/src/main/java/brooklyn/entity/rebind/BasicPolicyRebindSupport.java

package brooklyn.entity.rebind;

import static brooklyn.entity.basic.Entities.sanitize;

import java.util.Collections;
import java.util.Map;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import brooklyn.entity.rebind.dto.MementosGenerators;
import brooklyn.location.basic.AbstractLocation;
import brooklyn.mementos.PolicyMemento;
import brooklyn.policy.basic.AbstractPolicy;

public class BasicPolicyRebindSupport implements RebindSupport<PolicyMemento> {

    protected static final Logger LOG = LoggerFactory.getLogger(BasicPolicyRebindSupport.class);
    
    private final AbstractPolicy policy;
    
    public BasicPolicyRebindSupport(AbstractPolicy policy) {
        this.policy = policy;
    }
    
    @Override
    public PolicyMemento getMemento() {
        return getMementoWithProperties(Collections.<String,Object>emptyMap());
    }

    protected PolicyMemento getMementoWithProperties(Map<String,?> props) {
        PolicyMemento memento = MementosGenerators.newPolicyMementoBuilder(policy).customFields(props).build();
    	if (LOG.isTraceEnabled()) LOG.trace("Creating memento for policy {}({}): displayName={}; flags={}; " +
    			"customProperties={}; ",
    			new Object[] {memento.getType(), memento.getId(), memento.getDisplayName(),  
                sanitize(memento.getFlags()), sanitize(memento.getCustomFields())});
    	return memento;
    }

    @Override
    public void reconstruct(RebindContext rebindContext, PolicyMemento memento) {
    	if (LOG.isTraceEnabled()) LOG.trace("Reconstructing policy {}({}): displayName={}; flags={}; " +
    			"customProperties={}",
    			new Object[] {memento.getType(), memento.getId(), memento.getDisplayName(),  
				sanitize(memento.getFlags()), sanitize(memento.getCustomFields())});

    	// Note that the flags have been set in the constructor
        policy.setName(memento.getDisplayName());
        
        doReconsruct(rebindContext, memento);
        
        if (policy instanceof AbstractPolicy) {
            ((AbstractPolicy)policy).reconstruct();
        } else {
            LOG.info("rebind() not being called, because policy is not of type AbstractPolicy: type={}; policy={}", policy.getClass(), policy);
        }
    }

    /**
     * For overriding, to give custom reconsruct behaviour.
     */
    protected void doReconsruct(RebindContext rebindContext, PolicyMemento memento) {
        // default is no-op
    }
}