sigil/org.cauldron.bld.core/src/org/apache/felix/sigil/model/AbstractModelElement.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * 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
 * with the License.  You may obtain a copy of the License at
 * 
 *   http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

package org.apache.felix.sigil.model;

import java.io.Serializable;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;


public abstract class AbstractModelElement implements IModelElement {
	
	private static final long serialVersionUID = 1L;

	private IModelElement parent;
	
    private String description;
    private transient Map<Object, Object> meta;
    private Map<Serializable, Serializable> serializedMeta;
    private OverrideOptions override;
    
    protected final ModelElementSupport support;

    public AbstractModelElement(String description) {
    	support = new ModelElementSupport(this);
    	this.description = description.intern();
        this.meta = new HashMap<Object, Object>();
        this.serializedMeta = new HashMap<Serializable, Serializable>();
    }

    public String getElementDescription() {
        return description;
    }

    public Map<Object, Object> getMeta() {
        return meta;
    }

    public void setMeta(Map<Object, Object> meta) {
        this.meta = meta;
    }

    @Override
    public AbstractModelElement clone() {
		try {
	        AbstractModelElement clone = (AbstractModelElement) super.clone();
	   
	        clone.meta = new HashMap<Object, Object>(meta);

	        return clone;
		} catch (CloneNotSupportedException e) {
			// can't happen but make compiler happy
			throw new IllegalStateException(e);
		}
    }

    @SuppressWarnings("unchecked")
	public <T extends IModelElement> T getAncestor(Class<T> type) {
    	IModelElement parent = this.parent;
    	
    	while ( parent != null ) {
    		if ( type.isInstance( parent ) ) {
    			return (T) parent;
    		}
    		parent = parent.getParent();
    	}
    	
		return null;
	}

	public IModelElement getParent() {
		return parent;
	}
	
	public void setParent( IModelElement parent ) {
		if ( parent != null ) {
			if ( this.parent != null && this.parent != parent ) {
				throw new IllegalStateException( "Parent already installed");
			}
		}
		
		this.parent = parent;
	}
	
    public void checkValid() throws InvalidModelException {
    	for ( String req : getRequiredProperties() ) {
    		try {
				if ( getProperty( req ) == null ) {
					throw new InvalidModelException(this, "Missing property " + req );
				}
			} catch (NoSuchMethodException e) {
				throw new InvalidModelException( this, "No such property " + req );
			}
    	}
	}

	public Object getProperty(String name) throws NoSuchMethodException {
		return support.getProperty(name);
	}

	public void setProperty(String name, Object value)
			throws NoSuchMethodException {
		support.setProperty(name, value);
	}

	public void addProperty(String name, Object value)
			throws NoSuchMethodException {
		support.addProperty(name, value);
	}

	public void removeProperty(String name, Object value)
			throws NoSuchMethodException {
		support.removeProperty(name, value);
	}

	public Object getDefaultPropertyValue(String name) {
		return support.getDefaultPropertyValue( name );
	}

	public Set<String> getPropertyNames() {
		return support.getPropertyNames();
	}

	public Set<String> getRequiredProperties() {
		return Collections.emptySet();
	}

	protected Object writeReplace() {
        AbstractModelElement clone = clone();

        for (Map.Entry<Object, Object> e : clone.meta.entrySet()) {
            if (e.getKey() instanceof Serializable && e.getValue() instanceof Serializable) {
                serializedMeta.put((Serializable) e.getKey(), (Serializable) e.getValue());
            }
        }

        clone.meta.clear();

        return clone;
    }

    public Class<?> getPropertyType(String name) throws NoSuchMethodException {
		return support.getPropertyType(name);
	}

	protected Object readResolve() {
        this.meta = new HashMap<Object, Object>(serializedMeta);
        serializedMeta.clear();
        return this;
    }

	public OverrideOptions getOverride() {
		return override;
	}

	public void setOverride(OverrideOptions override) {
		this.override = override;
	}
}