imagemap.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。

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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.wicket.markup.html.link;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

import org.apache.wicket.IClusterable;
import org.apache.wicket.markup.ComponentTag;
import org.apache.wicket.markup.MarkupStream;
import org.apache.wicket.markup.html.WebMarkupContainer;


/**
 * An image map holds links with different hot-area shapes.
 * 
 * @author Jonathan Locke
 */
public final class ImageMap extends WebMarkupContainer
{
	private static final long serialVersionUID = 1L;

	/** list of shape links. */
	private final List shapeLinks = new ArrayList();

	/**
	 * A shape that has a circle form.
	 */
	private static final class CircleLink extends ShapeLink
	{
		private static final long serialVersionUID = 1L;

		/** The circle's radius. */
		private final int radius;

		/** Upper left x */
		private final int x;

		/** Upper left y */
		private final int y;

		/**
		 * Construct.
		 * 
		 * @param x
		 *            left upper x
		 * @param y
		 *            left upper y
		 * @param radius
		 *            the circles' radius
		 * @param link
		 *            the link
		 */
		public CircleLink(final int x, final int y, final int radius, final Link link)
		{
			super(link);
			this.x = x;
			this.y = y;
			this.radius = radius;
		}

		/**
		 * @see org.apache.wicket.markup.html.link.ImageMap.ShapeLink#getCoordinates()
		 */
		String getCoordinates()
		{
			return x + "," + y + "," + radius;
		}

		/**
		 * @see org.apache.wicket.markup.html.link.ImageMap.ShapeLink#getType()
		 */
		String getType()
		{
			return "circle";
		}
	}

	/**
	 * A shape that has a free (polygon) form.
	 */
	private static final class PolygonLink extends ShapeLink
	{
		private static final long serialVersionUID = 1L;

		/** Its coordinates. */
		private final int[] coordinates;

		/**
		 * Construct.
		 * 
		 * @param coordinates
		 *            the polygon coordinates
		 * @param link
		 *            the link
		 */
		public PolygonLink(final int[] coordinates, final Link link)
		{
			super(link);
			this.coordinates = coordinates;
		}

		/**
		 * @see org.apache.wicket.markup.html.link.ImageMap.ShapeLink#getCoordinates()
		 */
		String getCoordinates()
		{
			final StringBuffer buffer = new StringBuffer();
			for (int i = 0; i < coordinates.length; i++)
			{
				buffer.append(coordinates[i]);

				if (i < (coordinates.length - 1))
				{
					buffer.append(',');
				}
			}
			return buffer.toString();
		}

		/**
		 * @see org.apache.wicket.markup.html.link.ImageMap.ShapeLink#getType()
		 */
		String getType()
		{
			return "polygon";
		}
	}

	/**
	 * A shape that has a rectangular form.
	 */
	private static final class RectangleLink extends ShapeLink
	{
		private static final long serialVersionUID = 1L;

		/** left upper x. */
		private final int x1;

		/** right bottom x. */
		private final int x2;

		/** left upper y. */
		private final int y1;

		/** right bottom y. */
		private final int y2;

		/**
		 * Construct.
		 * 
		 * @param x1
		 *            left upper x
		 * @param y1
		 *            left upper y
		 * @param x2
		 *            right bottom x
		 * @param y2
		 *            right bottom y
		 * @param link
		 *            the link
		 */
		public RectangleLink(final int x1, final int y1, final int x2, final int y2, final Link link)
		{
			super(link);
			this.x1 = x1;
			this.y1 = y1;
			this.x2 = x2;
			this.y2 = y2;
		}

		/**
		 * @see org.apache.wicket.markup.html.link.ImageMap.ShapeLink#getCoordinates()
		 */
		String getCoordinates()
		{
			return x1 + "," + y1 + "," + x2 + "," + y2;
		}

		/**
		 * @see org.apache.wicket.markup.html.link.ImageMap.ShapeLink#getType()
		 */
		String getType()
		{
			return "rectangle";
		}
	}

	/**
	 * Base class for shaped links.
	 */
	private static abstract class ShapeLink implements IClusterable
	{
		/**
		 * 
		 */
		private static final long serialVersionUID = 1L;
		/** The link. */
		private final Link link;

		/**
		 * Constructor.
		 * 
		 * @param link
		 *            The link
		 */
		public ShapeLink(final Link link)
		{
			this.link = link;
		}

		/**
		 * The shape as a string using the given request cycle; will be used for rendering.
		 * 
		 * @return The shape as a string
		 */
		public String toString()
		{
			// Add any popup script
			final String popupJavaScript;

			if (link.getPopupSettings() != null)
			{
				popupJavaScript = link.getPopupSettings().getPopupJavaScript();
			}
			else
			{
				popupJavaScript = null;
			}

			return "<area shape=\"" + getType() + "\"" + " coords=\"" +
					getCoordinates() +
					"\"" +
					" href=\"" +
					link.getURL() +
					"\""
					// Output the markup ID if that was specified, so we can link tooltips, etc. to
					// it.
					+ (link.getOutputMarkupId() ? " id=\"" + link.getMarkupId() + "\"" : "") +
					((popupJavaScript == null) ? "" : (" onClick = \"" + popupJavaScript + "\"")) +
					">";
		}

		/**
		 * Gets the coordinates of the shape.
		 * 
		 * @return The coordinates of the shape
		 */
		abstract String getCoordinates();

		/**
		 * Gets the shape type.
		 * 
		 * @return the shape type
		 */
		abstract String getType();
	}

	/**
	 * Constructor.
	 * 
	 * @param id
	 *            See Component
	 */
	public ImageMap(final String id)
	{
		super(id);
	}

	/**
	 * Adds a circle link.
	 * 
	 * @param x1
	 *            top left x
	 * @param y1
	 *            top left y
	 * @param radius
	 *            the radius
	 * @param link
	 *            the link
	 * @return This
	 */
	public ImageMap addCircleLink(final int x1, final int y1, final int radius, final Link link)
	{
		add(link);
		shapeLinks.add(new CircleLink(x1, y1, radius, link));
		return this;
	}

	/**
	 * Adds a polygon link.
	 * 
	 * @param coordinates
	 *            the coordinates for the polygon
	 * @param link
	 *            the link
	 * @return This
	 */
	public ImageMap addPolygonLink(final int[] coordinates, final Link link)
	{
		add(link);
		shapeLinks.add(new PolygonLink(coordinates, link));
		return this;
	}

	/**
	 * Adds a rectangular link.
	 * 
	 * @param x1
	 *            top left x
	 * @param y1
	 *            top left y
	 * @param x2
	 *            bottom right x
	 * @param y2
	 *            bottom right y
	 * @param link
	 * @return This
	 */
	public ImageMap addRectangleLink(final int x1, final int y1, final int x2, final int y2,
			final Link link)
	{
		add(link);
		shapeLinks.add(new RectangleLink(x1, y1, x2, y2, link));
		return this;
	}

	/**
	 * Renders this component.
	 * 
	 * @see org.apache.wicket.Component#onRender(MarkupStream)
	 */
	protected void onRender(final MarkupStream markupStream)
	{
		// Get mutable copy of next tag
		final ComponentTag tag = markupStream.getTag().mutable();

		// Must be an img tag
		checkComponentTag(tag, "img");

		// Set map name to path
		tag.put("usemap", "#" + getPath());

		// Write out the tag
		renderComponentTag(tag);
		markupStream.next();

		// Write out the image map
		final StringBuffer imageMap = new StringBuffer();

		imageMap.append("\n<map name=\"").append(getPath()).append("\"> ");

		for (Iterator iterator = shapeLinks.iterator(); iterator.hasNext();)
		{
			final ShapeLink shapeLink = (ShapeLink)iterator.next();
			imageMap.append('\n');
			imageMap.append(shapeLink.toString());

			// Tell framework that this link was actually rendered
			getPage().componentRendered(shapeLink.link);
		}

		imageMap.append("\n</map>");
		getResponse().write(imageMap.toString());
	}
}