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This is the master POM file for Oracle's Implementation of the JSF 2.0 Specification.
There is a newer version: 2.4.0
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package com.sun.faces.component.visit;


import javax.faces.component.UIViewRoot;
import javax.faces.component.visit.VisitCallback;
import javax.faces.component.visit.VisitContext;
import javax.faces.component.visit.VisitResult;
import javax.faces.context.FacesContext;

/**
 * Tree visiting utilities.
 */
public class VisitUtils {

    /**
     * Performs a full tree visit, skipping iteration.
     *
     * @param context the FacesContext for this request
     * @param callback the callback to invoke during the visit
     * @return the result of visitTree() call
     */
    public static boolean doFullNonIteratingVisit(
        FacesContext  context,
        VisitCallback callback) {

        assert(context != null);
        assert(callback != null);

        UIViewRoot root = context.getViewRoot();
        VisitContext vContext = VisitContext.createVisitContext(context);

        startSkipIteration(context);

        try {
	    return root.visitTree(vContext, callback);
       }
       finally {
           endSkipIteration(context);
       }
    }
    

    /**
     * Tests whether we are skipping iteration.
     */
    public static boolean isSkippingIteration(FacesContext context) {

        Object hint = context.getAttributes().get(SKIP_ITERATION_HINT);
        return Boolean.TRUE.equals(hint);
    }

    public static void startStateSaveRestore(FacesContext context) {
        context.getAttributes().put(EXECUTE_STATE_SAVING_HINT, true);
    }

    public static void endStateSaveRestore(FacesContext context) {
        context.getAttributes().remove(EXECUTE_STATE_SAVING_HINT);
    }

    private static void startSkipIteration(FacesContext context) {

        // This code assumes that we won't have nested visits.
        assert(!isSkippingIteration(context));
        context.getAttributes().put(SKIP_ITERATION_HINT, true);
    }

    private static void endSkipIteration(FacesContext context) {

        assert(isSkippingIteration(context));
        context.getAttributes().remove(SKIP_ITERATION_HINT);
    }

    private static String SKIP_ITERATION_HINT =
        "javax.faces.visit.SKIP_ITERATION";

    private static String EXECUTE_STATE_SAVING_HINT =
        "javax.faces.visit.EXECUTE_STATE_SAVING";
}