ViewHandlingStrategyManager.java

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package com.sun.faces.application.view;

import static com.sun.faces.config.WebConfiguration.BooleanWebContextInitParameter.DisableFaceletJSFViewHandler;
import static com.sun.faces.config.WebConfiguration.BooleanWebContextInitParameter.DisableFaceletJSFViewHandlerDeprecated;

import com.sun.faces.config.WebConfiguration;

/**
 * Interface for working with multiple {@link com.sun.faces.application.view.ViewHandlingStrategy}
 * implementations.
 */
public class ViewHandlingStrategyManager {

    // The strategies associated with this instance
    private volatile ViewHandlingStrategy[] strategies;
    

    // ------------------------------------------------------------- Constructor


    /**
     * Be default, if {@link com.sun.faces.config.WebConfiguration.BooleanWebContextInitParameter#DisableFaceletJSFViewHandler}
     * isn't enabled, the strategies available (in order) will be {@link FaceletViewHandlingStrategy}
     * and {@link com.sun.faces.application.view.JspViewHandlingStrategy}.  
     * <p>
     * Otherwise, only the {@link com.sun.faces.application.view.JspViewHandlingStrategy} will be available.
     */
    public ViewHandlingStrategyManager() {

        WebConfiguration webConfig = WebConfiguration.getInstance();
        boolean pdlDisabled = webConfig.isOptionEnabled(DisableFaceletJSFViewHandler) || webConfig.isOptionEnabled(DisableFaceletJSFViewHandlerDeprecated);
        
        strategies = pdlDisabled
                      ? new ViewHandlingStrategy[] { new JspViewHandlingStrategy() }
                      : new ViewHandlingStrategy[] { new FaceletViewHandlingStrategy(), new JspViewHandlingStrategy() };

    }


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


    /**
     * <p>
     * Iterate through the available {@link com.sun.faces.application.view.ViewHandlingStrategy}
     * implementations.  The first one to return true from {@link com.sun.faces.application.view.ViewHandlingStrategy#handlesViewId(String)}
     * will be the {@link com.sun.faces.application.view.ViewHandlingStrategy} returned.
     * <p>
     *
     * @param viewId the viewId to match a {@link com.sun.faces.application.view.ViewHandlingStrategy} to
     *
     * @throws ViewHandlingStrategyNotFoundException if no match is found.
     *
     * @return a {@link com.sun.faces.application.view.ViewHandlingStrategy} for
     *  the specifed <code>viewId</code>
     */
    public ViewHandlingStrategy getStrategy(String viewId) {

        for (ViewHandlingStrategy strategy : strategies) {
            if (strategy.handlesViewId(viewId)) {
                return strategy;
            }
        }
        
        throw new ViewHandlingStrategyNotFoundException();
    }

    /**
     * @return the currently registered {@link com.sun.faces.application.view.ViewHandlingStrategy}
     *  implementations.
     */
    public ViewHandlingStrategy[] getViewHandlingStrategies() {
        return strategies.clone();
    }

    /**
     * Update the {@link com.sun.faces.application.view.ViewHandlingStrategy} implementations
     * to be applied when processing JSF requests.
     * @param stratagies the new view handling strategies
     */
    public synchronized void setViewHandlingStrategies(ViewHandlingStrategy[] stratagies) {
        this.strategies = stratagies.clone();
    }

}