VariableResolverImpl.java

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package com.sun.faces.el;

import javax.faces.context.FacesContext;
import javax.faces.el.EvaluationException;
import javax.faces.el.VariableResolver;
import javax.el.ELException;

import com.sun.faces.util.MessageUtils;

/**
 * <p>
 * Concrete implementation of <code>VariableResolver</code>.
 * </p>
 */
@SuppressWarnings("deprecation")
public class VariableResolverImpl extends VariableResolver {

    private VariableResolver delegate;

    // ------------------------------------------- Methods from VariableResolver

    // Specified by javax.faces.el.VariableResolver.resolveVariable()
    @Override
    public Object resolveVariable(FacesContext context, String name)
            throws EvaluationException {

        if (context == null) {
            String message = MessageUtils.getExceptionMessageString
                (MessageUtils.NULL_PARAMETERS_ERROR_MESSAGE_ID, "context");
            throw new NullPointerException(message);
        }
        if (name == null) {
            String message = MessageUtils.getExceptionMessageString
                (MessageUtils.NULL_PARAMETERS_ERROR_MESSAGE_ID, "name");
            throw new NullPointerException(message);
        }

        Object result;

        if (delegate != null) {
            result = delegate.resolveVariable(context, name);
        } else {
            try {
                result = context.getApplication().getELResolver().getValue(context.getELContext(), null, name);
            } catch (ELException elex) {
                throw new EvaluationException(elex);
            }
        }
        return result;

    }


    // ---------------------------------------------------------- Public Methods


    public void setDelegate(VariableResolver delegate) {

        this.delegate = delegate;

    }

    public VariableResolver getDelegate() {
        return this.delegate;
    }
}