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package com.sun.beans.decoder;

This is base class that simplifies access to entities (fields or properties). The name attribute specifies the name of the accessible entity. The element defines getter if it contains no argument or setter if it contains one argument. 
Author:
Sergey A. Malenkov
Since:
1.7/**
 * This is base class that simplifies access to entities (fields or properties).
 * The {@code name} attribute specifies the name of the accessible entity.
 * The element defines getter if it contains no argument
 * or setter if it contains one argument.
 *
 * @since 1.7
 *
 * @author Sergey A. Malenkov
 */
abstract class AccessorElementHandler extends ElementHandler {
    private String name;
    private ValueObject value;

    
Parses attributes of the element.
The following attributes are supported:

name
the name of the accessible entity
id
the identifier of the variable that is intended to store the result

Params:
name –   the attribute name
value –  the attribute value/**
     * Parses attributes of the element.
     * The following attributes are supported:
     * <dl>
     * <dt>name
     * <dd>the name of the accessible entity
     * <dt>id
     * <dd>the identifier of the variable that is intended to store the result
     * </dl>
     *
     * @param name   the attribute name
     * @param value  the attribute value
     */
    @Override
    public void addAttribute(String name, String value) {
        if (name.equals("name")) { // NON-NLS: the attribute name
            this.name = value;
        } else {
            super.addAttribute(name, value);
        }
    }

    
Adds the argument that is used to set the value of this element.
Params:
argument –  the value of the element that contained in this one/**
     * Adds the argument that is used to set the value of this element.
     *
     * @param argument  the value of the element that contained in this one
     */
    @Override
    protected final void addArgument(Object argument) {
        if (this.value != null) {
            throw new IllegalStateException("Could not add argument to evaluated element");
        }
        setValue(this.name, argument);
        this.value = ValueObjectImpl.VOID;
    }

    
Returns the value of this element.
Returns:
the value of this element/**
     * Returns the value of this element.
     *
     * @return the value of this element
     */
    @Override
    protected final ValueObject getValueObject() {
        if (this.value == null) {
            this.value = ValueObjectImpl.create(getValue(this.name));
        }
        return this.value;
    }

    
Returns the value of the entity with specified name. 
Params:
name –  the name of the accessible entity
Returns:
the value of the specified entity/**
     * Returns the value of the entity with specified {@code name}.
     *
     * @param name  the name of the accessible entity
     * @return the value of the specified entity
     */
    protected abstract Object getValue(String name);

    
Sets the new value for the entity with specified name. 
Params:
name –   the name of the accessible entity
value –  the new value for the specified entity/**
     * Sets the new value for the entity with specified {@code name}.
     *
     * @param name   the name of the accessible entity
     * @param value  the new value for the specified entity
     */
    protected abstract void setValue(String name, Object value);
}