    001// Licensed under the Apache License, Version 2.0 (the "License");
    002// you may not use this file except in compliance with the License.
    003// You may obtain a copy of the License at
    004//
    005//     http://www.apache.org/licenses/LICENSE-2.0
    006//
    007// Unless required by applicable law or agreed to in writing, software
    008// distributed under the License is distributed on an "AS IS" BASIS,
    009// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    010// See the License for the specific language governing permissions and
    011// limitations under the License.
    012package org.apache.tapestry5.services;
    013
    014import org.apache.tapestry5.Block;
    015import org.apache.tapestry5.alerts.Alert;
    016import org.apache.tapestry5.commons.services.TypeCoercer;
    017import org.apache.tapestry5.dom.Document;
    018import org.apache.tapestry5.runtime.RenderCommand;
    019
    020/**
    021 *
    022 * Service that provides methods that render {@link Block}s ({@code <t:block>} in the template),
    023 * component instances and {@link RenderCommand}s to a {@link String} or
    024 * {@link Document org.apache.tapestry5.dom.Document} in a programatic way.
    025 *
    026 *
    027 * This service was created for situations in which a page or component needs to generate some markup
    028 * that wouldn't be rendered normally, but for external use, such as e-mails, returning
    029 * HTML for AJAX requests or passing HTML instead of plain string for an {@link Alert}.
    030 *
    031 *
    032 * The name of this interface comes from <a href="https://issues.apache.org/jira/browse/TAP5-938">TAP5-938</a>:
    033 * <em>Expose ability to render a portion of a page (a Block, Component, etc.) without using internal services</em>.
    034 *
    035 * @since 5.4
    036 */
    037public interface PartialTemplateRenderer
    038{
    039    /**
    040     *
    041     * Renders an object, probably a {@link Block} or component instance, to a string.
    042     * This method supposes any kind of initialization needed
    043     * was already done. CSS and JavaScript inclusions or importings are ignored.
    044     * The object must implement {@link RenderCommand} or being able to be coerced to it
    045     * by {@link TypeCoercer}.
    046     *
    047     * @param object an object, probably a {@link Block} or component instance or {@link RenderCommand}.
    048     * @throws IllegalArgumentException if the object isn't a {@link RenderCommand} and cannot be coerced to it by {@link TypeCoercer}.
    049     */
    050    String render(Object object);
    051
    052    /**
    053     * Renders an object to a {@link Document} following the same rules as {@link #render(Object)}
    054     * This method supposes any kind of initialization needed
    055     * was already done. CSS and JavaScript inclusions or importings are ignored.
    056     *
    057     * @param object to render, a {@link RenderCommand}, or {@linkplain TypeCoercer coercible} to one
    058     * @return a {@link Document}.
    059     */
    060    Document renderAsDocument(Object object);
    061
    062}