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

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package org.glassfish.grizzly.attributes;

import org.glassfish.grizzly.utils.NullaryFunction;

/** 
 * The interface declares, that {@link AttributeHolder} supports
 * indexed {@link Attribute} access.
 *
 * @see AttributeHolder
 */
public interface IndexedAttributeAccessor {

    /** 
     * Internal method for dynamic attribute support.
     * Return the value of the attribute by index.
     * @param index the attribute index
     * @return the value of the attribute by index
     */
    public Object getAttribute(int index);

    /** 
     * Internal method for dynamic attribute support.
     * Return the value of the attribute by index.  If
     * the attribute with such index is not set, set it to the
     * default value, using the initializer, and return the default.
     * @param index the attribute index
     * @param initializer the default value {@link NullaryFunction}
     * @return the value of the attribute by index
     * @since 2.3.18
     */
    public Object getAttribute(int index, NullaryFunction initializer);
    
    /** 
     * Internal method for dynamic attribute support.
     * Set the attribute with the index to value.
     * @param index the attribute index
     * @param value the value
     */
    public void setAttribute(int index, Object value);
    
    /** 
     * Internal method for dynamic attribute support.
     * Removes the attribute with the index and returns its previous value.
     * 
     * @param index the attribute index
     * @return the previous value associated with the attribute
     * @since 2.3.18
     */
    public Object removeAttribute(int index);
    
}