markupcontainer.java

Wicket一个开发Java Web应用程序框架。它使得开发web应用程序变得容易而轻松。 Wicket利用一个POJO data beans组件使得它可以与任何持久层技术相结合。

			return 0;
		}
		else if (children instanceof Object[])
		{
			final Object[] children = (Object[])this.children;
			for (int i = 0; i < children.length; i++)
			{
				if (getId(children[i]).equals(child.getId()))
				{
					return i;
				}
			}
		}
		return -1;
	}

	private final Component children_remove(Component component)
	{
		int index = children_indexOf(component);
		if (index != -1)
		{
			return children_remove(index);
		}
		return null;
	}

	private final Component children_remove(int index)
	{
		if (children instanceof Component || children instanceof ComponentSourceEntry)
		{
			if (index == 0)
			{
				final Component removed = (Component)postprocess(children, true, null, -1);
				children = null;
				return removed;
			}
			else
			{
				throw new IndexOutOfBoundsException();
			}
		}
		else
		{
			Object[] c = ((Object[])children);
			final Object removed = c[index];
			if (c.length == 2)
			{
				if (index == 0)
				{
					children = c[1];
				}
				else if (index == 1)
				{
					children = c[0];
				}
				else
				{
					throw new IndexOutOfBoundsException();
				}
			}
			else
			{
				Object[] newChildren = new Object[c.length - 1];
				int j = 0;
				for (int i = 0; i < c.length; i++)
				{
					if (i != index)
					{
						newChildren[j++] = c[i];
					}
				}
				children = newChildren;
			}
			return (Component)postprocess(removed, true, null, -1);
		}
	}

	private final Object children_set(int index, Object child, boolean reconstruct)
	{
		Object replaced;
		if (index < children_size())
		{
			if (children == null || children instanceof Component ||
				children instanceof ComponentSourceEntry)
			{
				replaced = children;
				children = child;
			}
			else
			{
				final Object[] children = (Object[])this.children;
				replaced = children[index];
				children[index] = child;
			}
		}
		else
		{
			throw new IndexOutOfBoundsException();
		}
		return postprocess(replaced, reconstruct, null, -1);
	}

	private final Component children_set(int index, Component child)
	{
		return (Component)children_set(index, child, true);
	}

	private final int children_size()
	{
		if (children == null)
		{
			return 0;
		}
		else
		{
			if (children instanceof Component || children instanceof ComponentSourceEntry)
			{
				return 1;
			}
			return ((Object[])children).length;
		}
	}

	/**
	 * Ensure that there is space in childForId map for a new entry before adding it.
	 * 
	 * @param child
	 *            The child to put into the map
	 * @return Any component that was replaced
	 */
	private final Component put(final Component child)
	{
		int index = children_indexOf(child);
		if (index == -1)
		{
			children_add(child);
			return null;
		}
		else
		{
			return children_set(index, child);
		}
	}

	/**
	 * @param component
	 *            Component being removed
	 */
	private final void removedComponent(final Component component)
	{
		// Notify Page that component is being removed
		final Page page = component.findPage();
		if (page != null)
		{
			page.componentRemoved(component);
		}

		component.detach();

		// Component is removed
		component.setParent(null);
	}

	/**
	 * Renders the next element of markup in the given markup stream.
	 * 
	 * @param markupStream
	 *            The markup stream
	 */
	private final void renderNext(final MarkupStream markupStream)
	{
		// Get the current markup element
		final MarkupElement element = markupStream.get();

		// If it a tag like <wicket..> or <span wicket:id="..." >
		if ((element instanceof ComponentTag) && !markupStream.atCloseTag())
		{
			// Get element as tag
			final ComponentTag tag = (ComponentTag)element;

			// Get component id
			final String id = tag.getId();

			// Get the component for the id from the given container
			final Component component = get(id);

			// Failed to find it?
			if (component != null)
			{
				component.render(markupStream);
			}
			else
			{
				// 2rd try: Components like Border and Panel might implement
				// the ComponentResolver interface as well.
				MarkupContainer container = this;
				while (container != null)
				{
					if (container instanceof IComponentResolver)
					{
						if (((IComponentResolver)container).resolve(this, markupStream, tag))
						{
							return;
						}
					}

					container = container.findParent(MarkupContainer.class);
				}

				// 3rd try: Try application's component resolvers
				final List componentResolvers = getApplication().getPageSettings()
					.getComponentResolvers();
				final Iterator iterator = componentResolvers.iterator();
				while (iterator.hasNext())
				{
					final IComponentResolver resolver = (IComponentResolver)iterator.next();
					if (resolver.resolve(this, markupStream, tag))
					{
						return;
					}
				}

				if (tag instanceof WicketTag)
				{
					if (((WicketTag)tag).isChildTag())
					{
						markupStream.throwMarkupException("Found " + tag.toString() +
							" but no <wicket:extend>");
					}
					else
					{
						markupStream.throwMarkupException("Failed to handle: " + tag.toString());
					}
				}

				// No one was able to handle the component id
				markupStream.throwMarkupException("Unable to find component with id '" + id +
					"' in " + this + ". This means that you declared wicket:id=" + id +
					" in your markup, but that you either did not add the " +
					"component to your page at all, or that the hierarchy does not match.");
			}
		}
		else
		{
			// Render as raw markup
			if (log.isDebugEnabled())
			{
				log.debug("Rendering raw markup");
			}
			getResponse().write(element.toCharSequence());
			markupStream.next();
		}
	}

	/**
	 * Get the markup stream for this component.
	 * 
	 * @return The markup stream for this component, or if it doesn't have one, the markup stream
	 *         for the nearest parent which does have one
	 */
	protected final MarkupStream findMarkupStream()
	{
		// Start here
		MarkupContainer c = this;

		// Walk up hierarchy until markup found
		while (c.getMarkupStream() == null)
		{
			// Check parent
			c = c.getParent();

			// Are we at the top of the hierarchy?
			if (c == null)
			{
				// Failed to find markup stream
				throw new WicketRuntimeException(exceptionMessage("No markup found"));
			}
		}

		return c.getMarkupStream();
	}

	/**
	 * Handle the container's body. If your override of this method does not advance the markup
	 * stream to the close tag for the openTag, a runtime exception will be thrown by the framework.
	 * 
	 * @param markupStream
	 *            The markup stream
	 * @param openTag
	 *            The open tag for the body
	 */
	protected void onComponentTagBody(final MarkupStream markupStream, final ComponentTag openTag)
	{
		renderComponentTagBody(markupStream, openTag);
	}

	/**
	 * Renders this component. This implementation just calls renderComponent.
	 * 
	 * @param markupStream
	 */
	protected void onRender(final MarkupStream markupStream)
	{
		renderComponent(markupStream);
	}

	/**
	 * Renders this component and all sub-components using the given markup stream.
	 * 
	 * @param markupStream
	 *            The markup stream
	 */
	protected void renderAll(final MarkupStream markupStream)
	{
		// Loop through the markup in this container
		while (markupStream.hasMore())
		{
			// Element rendering is responsible for advancing markup stream!
			final int index = markupStream.getCurrentIndex();
			renderNext(markupStream);
			if (index == markupStream.getCurrentIndex())
			{
				markupStream.throwMarkupException("Component at markup stream index " + index +
					" failed to advance the markup stream");
			}
		}
	}

	/**
	 * Renders markup for the body of a ComponentTag from the current position in the given markup
	 * stream. If the open tag passed in does not require a close tag, nothing happens. Markup is
	 * rendered until the closing tag for openTag is reached.
	 * 
	 * @param markupStream
	 *            The markup stream
	 * @param openTag
	 *            The open tag
	 */
	protected final void renderComponentTagBody(final MarkupStream markupStream,
		final ComponentTag openTag)
	{
		// If the open tag requires a close tag
		boolean render = openTag.requiresCloseTag();
		if (render == false)
		{
			// Tags like <p> do not require a close tag, but they may have.
			render = !openTag.hasNoCloseTag();
		}
		if (render == true)
		{
			// Loop through the markup in this container
			while (markupStream.hasMore() && !markupStream.get().closes(openTag))
			{
				// Render markup element. Doing so must advance the markup
				// stream
				final int index = markupStream.getCurrentIndex();
				renderNext(markupStream);
				if (index == markupStream.getCurrentIndex())
				{
					markupStream.throwMarkupException("Markup element at index " + index +
						" failed to advance the markup stream");
				}
			}
		}
	}

	/**
	 * Set markup stream for this container.
	 * 
	 * @param markupStream
	 *            The markup stream
	 */
	protected final void setMarkupStream(final MarkupStream markupStream)
	{
		this.markupStream = markupStream;
	}

	private static class ComponentSourceEntry extends org.apache.wicket.ComponentSourceEntry
	{
		private ComponentSourceEntry(MarkupContainer container, Component component,
			IComponentSource componentSource)
		{
			super(container, component, componentSource);
		}

		private static final long serialVersionUID = 1L;

		protected void setChild(MarkupContainer parent, int index, Component child)
		{
			parent.children_set(index, child, false);
		}
	}

	void detachChildren()
	{
		super.detachChildren();

		for (int i = children_size(); i-- > 0;)
		{
			Object child = children_get(i, false);
			if (child instanceof Component)
			{
				Component component = (Component)child;
				component.detach();

				if (child instanceof IComponentSourceProvider)
				{
					ComponentSourceEntry entry = new ComponentSourceEntry(this, component,
						((IComponentSourceProvider)child).getComponentSource());
					children_set(i, entry, false);
				}
				else if (component.isAuto())
				{
					children_remove(i);
				}
			}
		}
	}

	void internalMarkRendering()
	{
		super.internalMarkRendering();
		final int size = children_size();
		for (int i = 0; i < size; i++)
		{
			final Component child = children_get(i);
			child.internalMarkRendering();
		}
	}

	private Component[] copyChildren()
	{
		int size = children_size();
		Component result[] = new Component[size];
		for (int i = 0; i < size; ++i)
		{
			result[i] = children_get(i);
		}
		return result;
	}

	void onBeforeRenderChildren()
	{
		super.onBeforeRenderChildren();

		// We need to copy the children list because the children components can
		// modify the hierarchy in their onBeforeRender.
		Component[] children = copyChildren();
		try
		{
			// Loop through child components
			for (int i = 0; i < children.length; i++)
			{
				// Get next child
				final Component child = children[i];

				// Call begin request on the child
				// We need to check whether the child's wasn't removed from the
				// component in the meanwhile (e.g. from another's child
				// onBeforeRender)
				if (child.getParent() == this)
				{
					child.beforeRender();
				}
			}
		}
		catch (RuntimeException ex)
		{
			if (ex instanceof WicketRuntimeException)
			{
				throw ex;
			}
			else
			{
				throw new WicketRuntimeException("Error attaching this container for rendering: " +
					this, ex);
			}
		}
	}

	void onAfterRenderChildren()
	{
		// Loop through child components
		final Iterator iter = iterator();
		while (iter.hasNext())
		{
			// Get next child
			final Component child = (Component)iter.next();

			// Call end request on the child
			child.afterRender();
		}
		super.onAfterRenderChildren();
	}

	/**
	 * @return True if this markup container has associated markup
	 */
	public boolean hasAssociatedMarkup()
	{
		return getApplication().getMarkupSettings().getMarkupCache().hasAssociatedMarkup(this);
	}

	/**
	 * @see org.apache.wicket.Component#setRenderAllowed()
	 */
	void setRenderAllowed()
	{
		super.setRenderAllowed();

		visitChildren(new IVisitor()
		{
			public Object component(final Component component)
			{
				// Find out if this component can be rendered
				final boolean renderAllowed = component.isActionAuthorized(RENDER);
				// Authorize rendering
				component.setRenderAllowed(renderAllowed);
				return IVisitor.CONTINUE_TRAVERSAL;
			}
		});
	}
}