| // Copyright 2004 The Apache Software Foundation |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| package org.apache.tapestry; |
| |
| import org.apache.commons.logging.Log; |
| import org.apache.commons.logging.LogFactory; |
| import org.apache.tapestry.engine.IPageLoader; |
| import org.apache.tapestry.engine.IPageSource; |
| import org.apache.tapestry.engine.ITemplateSource; |
| import org.apache.tapestry.parse.ComponentTemplate; |
| import org.apache.tapestry.spec.IComponentSpecification; |
| |
| /** |
| * Base implementation for most components that use an HTML template. |
| * |
| * @author Howard Lewis Ship |
| * @version $Id$ |
| * |
| **/ |
| |
| public class BaseComponent extends AbstractComponent |
| { |
| private static final Log LOG = LogFactory.getLog(BaseComponent.class); |
| |
| private static final int OUTER_INIT_SIZE = 5; |
| |
| private IRender[] _outer; |
| private int _outerCount = 0; |
| |
| /** |
| * Adds an element as an outer element for the receiver. Outer |
| * elements are elements that should be directly rendered by the |
| * receiver's <code>render()</code> method. That is, they are |
| * top-level elements on the HTML template. |
| * |
| * |
| **/ |
| |
| protected void addOuter(IRender element) |
| { |
| if (_outer == null) |
| { |
| _outer = new IRender[OUTER_INIT_SIZE]; |
| _outer[0] = element; |
| |
| _outerCount = 1; |
| return; |
| } |
| |
| // No more room? Make the array bigger. |
| |
| if (_outerCount == _outer.length) |
| { |
| IRender[] newOuter; |
| |
| newOuter = new IRender[_outer.length * 2]; |
| |
| System.arraycopy(_outer, 0, newOuter, 0, _outerCount); |
| |
| _outer = newOuter; |
| } |
| |
| _outer[_outerCount++] = element; |
| } |
| |
| /** |
| * |
| * Reads the receiver's template and figures out which elements wrap which |
| * other elements. |
| * |
| * <P>This is coded as a single, big, ugly method for efficiency. |
| * |
| **/ |
| |
| private void readTemplate(IRequestCycle cycle, IPageLoader loader) |
| { |
| IPageSource pageSource = loader.getEngine().getPageSource(); |
| |
| if (LOG.isDebugEnabled()) |
| LOG.debug(this +" reading template"); |
| |
| ITemplateSource source = loader.getTemplateSource(); |
| ComponentTemplate componentTemplate = source.getTemplate(cycle, this); |
| |
| // Most of the work is done inside the loader class. |
| // We instantiate it just to invoke process() on it. |
| |
| new BaseComponentTemplateLoader(cycle, loader, this, componentTemplate, pageSource).process(); |
| |
| if (LOG.isDebugEnabled()) |
| LOG.debug(this +" finished reading template"); |
| } |
| |
| /** |
| * Renders the top level components contained by the receiver. |
| * |
| * @since 2.0.3 |
| **/ |
| |
| protected void renderComponent(IMarkupWriter writer, IRequestCycle cycle) |
| { |
| if (LOG.isDebugEnabled()) |
| LOG.debug("Begin render " + getExtendedId()); |
| |
| for (int i = 0; i < _outerCount; i++) |
| _outer[i].render(writer, cycle); |
| |
| if (LOG.isDebugEnabled()) |
| LOG.debug("End render " + getExtendedId()); |
| } |
| |
| /** |
| * Loads the template for the component, then invokes |
| * {@link AbstractComponent#finishLoad(IRequestCycle, IPageLoader, IComponentSpecification)}. |
| * Subclasses must invoke this method first, |
| * before adding any additional behavior, though its usually |
| * simpler to override {@link #finishLoad()} instead. |
| * |
| **/ |
| |
| public void finishLoad(IRequestCycle cycle, IPageLoader loader, IComponentSpecification specification) |
| { |
| readTemplate(cycle, loader); |
| |
| super.finishLoad(cycle, loader, specification); |
| } |
| } |