jakarta.faces.component.UINamingContainer Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of jakarta.faces-api Show documentation
Jakarta Faces defines an MVC framework for building user interfaces for web applications, including UI components, state management, event handing, input validation, page navigation, and support for internationalization and accessibility.
There is a newer version: 4.1.2
Show newest version
/*
 * Copyright (c) 1997, 2020 Oracle and/or its affiliates. All rights reserved.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 2.0, which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 *
 * This Source Code may also be made available under the following Secondary
 * Licenses when the conditions for such availability set forth in the
 * Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
 * version 2 with the GNU Classpath Exception, which is available at
 * https://www.gnu.org/software/classpath/license.html.
 *
 * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
 */

package jakarta.faces.component;

import static com.sun.faces.util.Util.coalesce;
import static jakarta.faces.component.UIViewRoot.UNIQUE_ID_PREFIX;
import static jakarta.faces.component.visit.VisitResult.COMPLETE;
import static java.util.logging.Level.SEVERE;

import java.util.Collection;
import java.util.logging.Logger;

import jakarta.faces.component.visit.VisitCallback;
import jakarta.faces.component.visit.VisitContext;
import jakarta.faces.context.FacesContext;

/**
 * 
 * UINamingContainer is a convenience base class for components that wish
 * to implement {@link NamingContainer} functionality.
 * 
 */

public class UINamingContainer extends UIComponentBase implements NamingContainer, UniqueIdVendor, StateHolder {

    // ------------------------------------------------------ Manifest Constants

    private static final Logger LOGGER = Logger.getLogger("jakarta.faces.component", "jakarta.faces.LogStrings");

    /**
     * 
     * The standard component type for this component.
     * 
     */
    public static final String COMPONENT_TYPE = "jakarta.faces.NamingContainer";

    /**
     * 
     * The standard component family for this component.
     * 
     */
    public static final String COMPONENT_FAMILY = "jakarta.faces.NamingContainer";

    /**
     * 
     * The context-param that allows the separator char for clientId strings to be set on a per-web application basis.
     * 
     *
     * @since 2.0
     */
    public static final String SEPARATOR_CHAR_PARAM_NAME = "jakarta.faces.SEPARATOR_CHAR";

    enum PropertyKeys {
        lastId
    }

    // ------------------------------------------------------------ Constructors

    /**
     * 
     * Create a new {@link UINamingContainer} instance with default property values.
     * 
     */
    public UINamingContainer() {
        super();
        setRendererType(null);
    }

    // -------------------------------------------------------------- Properties

    @Override
    public String getFamily() {
        return COMPONENT_FAMILY;
    }

    /**
     * 
     * Return the character used to separate segments of a clientId. The implementation must determine if there is a
     * <context-param> with the value given by the value of the symbolic constant
     * {@link #SEPARATOR_CHAR_PARAM_NAME}. If there is a value for this param, the first character of the value must be
     * returned from this method. Otherwise, the value of the symbolic constant {@link NamingContainer#SEPARATOR_CHAR} must
     * be returned.
     * 
     *
     * @param context the {@link FacesContext} for the current request
     * @return the separator char.
     * @since 2.0
     */
    public static char getSeparatorChar(FacesContext context) {

        if (context == null) {
            if (LOGGER.isLoggable(SEVERE)) {
                LOGGER.log(SEVERE, "UINamingContainer.getSeparatorChar() called with null FacesContext. This indicates a SEVERE error. Returning {0}",
                        SEPARATOR_CHAR);
            }

            return SEPARATOR_CHAR;
        }

        Character separatorChar = (Character) context.getAttributes().get(SEPARATOR_CHAR_PARAM_NAME);
        if (separatorChar == null) {
            String initParam = context.getExternalContext().getInitParameter(SEPARATOR_CHAR_PARAM_NAME);
            separatorChar = SEPARATOR_CHAR;
            if (initParam != null) {
                initParam = initParam.trim();
                if (initParam.length() != 0) {
                    separatorChar = initParam.charAt(0);
                }
            }

            context.getAttributes().put(SEPARATOR_CHAR_PARAM_NAME, separatorChar);
        }

        return separatorChar;
    }

    /**
     * @return true if tree should be visited, false otherwise.
     * @see UIComponent#visitTree
     */
    @Override
    public boolean visitTree(VisitContext context, VisitCallback callback) {

        // NamingContainers can optimize partial tree visits by taking advantage
        // of the fact that it is possible to detect whether any ids to visit
        // exist underneath the NamingContainer. If no such ids exist, there
        // is no need to visit the subtree under the NamingContainer.
        Collection idsToVisit = context.getSubtreeIdsToVisit(this);

        // If we have ids to visit, let the superclass implementation
        // handle the visit
        if (!idsToVisit.isEmpty()) {
            return super.visitTree(context, callback);
        }

        // If we have no child ids to visit, just visit ourselves, if
        // we are visitable.
        if (isVisitable(context)) {
            FacesContext facesContext = context.getFacesContext();
            pushComponentToEL(facesContext, null);

            try {
                return context.invokeVisitCallback(this, callback) == COMPLETE;
            } finally {
                popComponentFromEL(facesContext);
            }
        }

        // Done visiting this subtree. Return false to allow
        // visit to continue.
        return false;
    }

    @Override
    public String createUniqueId(FacesContext context, String seed) {
        int lastId = coalesce(getLastId(), 0);
        setLastId(++lastId);

        return UNIQUE_ID_PREFIX + coalesce(seed, lastId);
    }

    // ----------------------------------------------------- Private Methods

    private Integer getLastId() {
        return (Integer) getStateHelper().get(PropertyKeys.lastId);
    }

    private void setLastId(Integer lastId) {
        getStateHelper().put(PropertyKeys.lastId, lastId);
    }

}