org.glassfish.grizzly.attributes.AttributeHolder Maven / Gradle / Ivy

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package org.glassfish.grizzly.attributes;

import java.util.Set;
import org.glassfish.grizzly.utils.NullaryFunction;

/**
 * Interface declares common functionality for objects, which have associated
 * {@link Attribute}s.
 *
 * @see IndexedAttributeHolder
 * @see NamedAttributeHolder
 * 
 * @author Alexey Stashok
 */
public interface AttributeHolder {
    /**
     * Remove a name/value object.
     * @param name - name of an attribute
     * @return  attribute which has been removed
     */
    public Object removeAttribute(String name);
    
    
    /**
     * Set a name/value object.
     * @param name - name of an attribute
     * @param value - value of named attribute
     */
    public void setAttribute(String name, Object value);

    
    /**
     * Return an object based on a name.
     * @param name - name of an attribute
     * @return - attribute value for the name, null if name
     *           does not exist in attributes
     */
    public Object getAttribute(String name);

    /**
     * Return an object based on a name.
     * @param name - name of an attribute
     * @param initializer the initializer to be used to assign a default attribute value,
     *          in case it hasn't been assigned
     * @return - attribute value for the name, null if name
     *           does not exist in attributes
     * 
     * @since 2.3.18
     */
    public Object getAttribute(String name, NullaryFunction initializer);

    /**
     * Return a {@link Set} of attribute names.
     * 
     * @return - {@link Set} of attribute names
     */
    public Set getAttributeNames();
    
    
    /**
     * Clear all the attributes.
     */
    public void clear();
    
    /**
     * Recycle AttributeHolder
     */
    public void recycle();
    
    /**
     * Get AttributeBuilder, associated with this holder
     * @return AttributeBuilder
     */
    public AttributeBuilder getAttributeBuilder();
    
    
    /**
     * If AttributeHolder supports attribute access by index - it will return
     * an {@link IndexedAttributeAccessor}, which will make {@link Attribute}
     * access as fast as access to array element.
     * 
     * @return {@link IndexedAttributeAccessor}.
     */
    public IndexedAttributeAccessor getIndexedAttributeAccessor();

    /**
     * Copies attributes from this AttributeHolder to the dstAttributes.
     * 
     * @param dstAttributes 
     */
    public void copyTo(AttributeHolder dstAttributes);

    /**
     * Copies attributes from the srcAttributes to this AttributeHolder
     * 
     * @param srcAttributes 
     */
    public void copyFrom(AttributeHolder srcAttributes);
}