ViewScopeContext.java

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package com.sun.faces.application.view;

import java.io.Serializable;
import java.lang.annotation.Annotation;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.enterprise.context.ContextNotActiveException;
import javax.enterprise.context.spi.Context;
import javax.enterprise.context.spi.Contextual;
import javax.enterprise.context.spi.CreationalContext;
import javax.faces.component.UIViewRoot;
import javax.faces.context.FacesContext;
import javax.faces.view.ViewScoped;

/**
 * The CDI context for CDI ViewScoped beans.
 */
public class ViewScopeContext implements Context, Serializable {

    /**
     * Stores the logger.
     */
    private static final Logger LOGGER = Logger.getLogger(ViewScopeContext.class.getName());
    /**
     * Stores the serial version UID.
     */
    private static final long serialVersionUID = -6245899073989073951L;

    /**
     * Constructor.
     */
    public ViewScopeContext() {
        if (LOGGER.isLoggable(Level.FINEST)) {
            LOGGER.log(Level.FINEST, "Creating ViewScope CDI context");
        }
    }

    /**
     * Assert the context is active, otherwise throw ContextNotActiveException.
     */
    @SuppressWarnings({"FinalPrivateMethod"})
    private final void assertNotReleased() {
        if (!isActive()) {
            if (LOGGER.isLoggable(Level.SEVERE)) {
                LOGGER.log(Level.SEVERE, "Trying to access ViewScope CDI context while it is not active");
            }
            throw new ContextNotActiveException();
        }
    }


    /**
     * Get the ViewScoped bean for the given contextual.
     *
     * @param <T> the type.
     * @param contextual the contextual.
     * @return the view scoped bean, or null if not found.
     */
    @Override
    public <T> T get(Contextual<T> contextual) {
        assertNotReleased();

        T result = null;
        
        FacesContext facesContext = FacesContext.getCurrentInstance();
        if (facesContext != null) {
            ViewScopeManager manager = ViewScopeManager.getInstance(facesContext);
            if (manager != null) {
                result = manager.getContextManager().getBean(facesContext, contextual);
            }
        }

        return result;
    }

    /**
     * Get the existing instance of the ViewScoped bean for the given contextual
     * or create a new one.
     *
     * @param <T> the type.
     * @param contextual the contextual.
     * @param creational the creational.
     * @return the instance.
     * @throws ContextNotActiveException when the context is not active.
     */
    @Override
    public <T> T get(Contextual<T> contextual, CreationalContext<T> creational) {
        assertNotReleased();

        T result = get(contextual);

        if (result == null) {
            FacesContext facesContext = FacesContext.getCurrentInstance();
            if (facesContext != null) {
                ViewScopeManager manager = ViewScopeManager.getInstance(facesContext);
                result = (T) manager.getContextManager().getBean(facesContext, contextual);
                if (result == null) {
                    result = (T) manager.getContextManager().createBean(facesContext, contextual, creational);
                }
            }
        }

        return result;
    }

    /**
     * Get the class of the scope object.
     *
     * @return the class.
     */
    @Override
    public Class<? extends Annotation> getScope() {
        return ViewScoped.class;
    }

    /**
     * Determine if the context is active.
     *
     * @return true if there is a view root, false otherwise.
     */
    @Override
    public boolean isActive() {
        boolean result = false;

        FacesContext facesContext = FacesContext.getCurrentInstance();
        if (facesContext != null) {
            UIViewRoot viewRoot = facesContext.getViewRoot();
            if (viewRoot != null) {
                result = true;
            }
        }

        return result;
    }
}