pre-wicket.1.2.5/wicket-extensions/src/main/java/wicket/extensions/markup/html/captcha/CaptchaImageResource.java - wicket - Git at Google

 /*
  * $Id: SmartLinkLabel.java 5860 2006-05-25 20:29:28 +0000 (Thu, 25 May 2006)
  * eelco12 $ $Revision: 5876 $ $Date: 2006-05-25 20:29:28 +0000 (Thu, 25 May
  * 2006) $
  *
  * ==============================================================================
  * 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 wicket.extensions.markup.html.captcha;

 import java.awt.BasicStroke;
 import java.awt.Color;
 import java.awt.Font;
 import java.awt.Graphics2D;
 import java.awt.Shape;
 import java.awt.font.FontRenderContext;
 import java.awt.font.TextLayout;
 import java.awt.geom.AffineTransform;
 import java.awt.image.BufferedImage;
 import java.awt.image.WritableRaster;
 import java.io.Serializable;
 import java.lang.ref.SoftReference;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
 import java.util.Random;

 import wicket.markup.html.image.resource.DynamicImageResource;
 import wicket.util.time.Time;

 /**
  * Generates a captcha image.
  *
  * @author Joshua Perlow
  */
 public final class CaptchaImageResource extends DynamicImageResource
 {
 	/**
 	 * This class is used to encapsulate all the filters that a character will
 	 * get when rendered. The changes are kept so that the size of the shapes
 	 * can be properly recorded and reproduced later, since it dynamically
 	 * generates the size of the captcha image. The reason I did it this way is
 	 * because none of the JFC graphics classes are serializable, so they cannot
 	 * be instance variables here. If anyone knows a better way to do this,
 	 * please let me know.
 	 */
 	private static final class CharAttributes implements Serializable
 	{
 		private static final long serialVersionUID = 1L;
 		private char c;
 		private String name;
 		private int rise;
 		private double rotation;
 		private double shearX;
 		private double shearY;

 		CharAttributes(char c, String name, double rotation, int rise, double shearX, double shearY)
 		{
 			this.c = c;
 			this.name = name;
 			this.rotation = rotation;
 			this.rise = rise;
 			this.shearX = shearX;
 			this.shearY = shearY;
 		}

 		char getChar()
 		{
 			return c;
 		}

 		String getName()
 		{
 			return name;
 		}

 		int getRise()
 		{
 			return rise;
 		}

 		double getRotation()
 		{
 			return rotation;
 		}

 		double getShearX()
 		{
 			return shearX;
 		}

 		double getShearY()
 		{
 			return shearY;
 		}
 	}

 	private static final long serialVersionUID = 1L;

 	private static int randomInt(int min, int max)
 	{
 		return (int)(Math.random() * (max - min) + min);
 	}

 	private static String randomString(int min, int max)
 	{
 		int num = randomInt(min, max);
 		byte b[] = new byte[num];
 		for (int i = 0; i < num; i++)
 			b[i] = (byte)randomInt('a', 'z');
 		return new String(b);
 	}

 	private String challengeId;
 	private final List charAttsList;

 	private List fontNames = Arrays.asList(new String[] { "Helventica", "Arial", "Courier" });
 	private final int fontSize;
 	private final int fontStyle;

 	private int height = 0;

 	/** Transient image data so that image only needs to be generated once per VM */
 	private transient SoftReference imageData;

 	private final int margin;

 	private int width = 0;

 	/**
 	 * Construct.
 	 */
 	public CaptchaImageResource()
 	{
 		this(randomString(6, 8));
 	}

 	/**
 	 * Construct.
 	 *
 	 * @param challengeId
 	 *            The id of the challenge
 	 */
 	public CaptchaImageResource(String challengeId)
 	{
 		this(challengeId, 48, 30);
 	}

 	/**
 	 * Construct.
 	 *
 	 * @param challengeId
 	 *            The id of the challenge
 	 * @param fontSize
 	 *            The font size
 	 * @param margin
 	 *            The image's margin
 	 */
 	public CaptchaImageResource(String challengeId, int fontSize, int margin)
 	{
 		this.challengeId = challengeId;
 		this.fontStyle = 1;
 		this.fontSize = fontSize;
 		this.margin = margin;
 		this.width = this.margin * 2;
 		this.height = this.margin * 2;
 		char[] chars = challengeId.toCharArray();
 		charAttsList = new ArrayList();
 		TextLayout text;
 		AffineTransform textAt;
 		Shape shape;
 		for (int i = 0; i < chars.length; i++)
 		{
 			String fontName = (String)fontNames.get(randomInt(0, fontNames.size()));
 			double rotation = Math.toRadians(randomInt(-35, 35));
 			int rise = randomInt(margin / 2, margin);
 			Random ran = new Random();
 			double shearX = ran.nextDouble() * 0.2;
 			double shearY = ran.nextDouble() * 0.2;
 			CharAttributes cf = new CharAttributes(chars[i], fontName, rotation, rise, shearX,
 					shearY);
 			charAttsList.add(cf);
 			text = new TextLayout(chars[i] + "", getFont(fontName), new FontRenderContext(null,
 					false, false));
 			textAt = new AffineTransform();
 			textAt.rotate(rotation);
 			textAt.shear(shearX, shearY);
 			shape = text.getOutline(textAt);
 			this.width += (int)shape.getBounds2D().getWidth();
 			if (this.height < (int)shape.getBounds2D().getHeight() + rise)
 			{
 				this.height = (int)shape.getBounds2D().getHeight() + rise;
 			}
 		}
 	}

 	/**
 	 * Gets the id for the challenge.
 	 *
 	 * @return The the id for the challenge
 	 */
 	public final String getChallengeId()
 	{
 		return challengeId;
 	}

 	/**
 	 * Causes the image to be redrawn the next time its requested.
 	 *
 	 * @see wicket.Resource#invalidate()
 	 */
 	public final void invalidate()
 	{
 		imageData = null;
 	}

 	/**
 	 * @see wicket.markup.html.image.resource.DynamicImageResource#getImageData()
 	 */
 	protected final byte[] getImageData()
 	{
 		// get image data is always called in sync block
 		byte[] data = null;
 		if (imageData != null)
 		{
 			data = (byte[])imageData.get();
 		}
 		if (data == null)
 		{
 			data = render();
 			imageData = new SoftReference(data);
 			setLastModifiedTime(Time.now());
 		}
 		return data;
 	}

 	private Font getFont(String fontName)
 	{
 		return new Font(fontName, fontStyle, fontSize);
 	}

 	/**
 	 * Renders this image
 	 *
 	 * @return The image data
 	 */
 	private final byte[] render()
 	{
 		while (true)
 		{
 			final BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
 			Graphics2D gfx = (Graphics2D)image.getGraphics();
 			gfx.setBackground(Color.WHITE);
 			int curWidth = margin;
 			for (int i = 0; i < charAttsList.size(); i++)
 			{
 				CharAttributes cf = (CharAttributes)charAttsList.get(i);
 				TextLayout text = new TextLayout(cf.getChar() + "", getFont(cf.getName()), gfx
 						.getFontRenderContext());
 				AffineTransform textAt = new AffineTransform();
 				textAt.translate(curWidth, height - cf.getRise());
 				textAt.rotate(cf.getRotation());
 				textAt.shear(cf.getShearX(), cf.getShearY());
 				Shape shape = text.getOutline(textAt);
 				curWidth += shape.getBounds().getWidth();
 				gfx.setXORMode(Color.BLACK);
 				gfx.fill(shape);
 			}

 			// XOR circle
 			int dx = randomInt(width, 2 * width);
 			int dy = randomInt(width, 2 * height);
 			int x = randomInt(0, width / 2);
 			int y = randomInt(0, height / 2);

 			gfx.setXORMode(Color.BLACK);
 			gfx.setStroke(new BasicStroke(randomInt(fontSize / 8, fontSize / 2)));
 			gfx.drawOval(x, y, dx, dy);

 			WritableRaster rstr = image.getRaster();
 			int[] vColor = new int[3];
 			int[] oldColor = new int[3];
 			Random vRandom = new Random(System.currentTimeMillis());

 			// noise
 			for (x = 0; x < width; x++)
 			{
 				for (y = 0; y < height; y++)
 				{
 					rstr.getPixel(x, y, oldColor);

 					// hard noise
 					vColor[0] = 0 + (int)(Math.floor(vRandom.nextFloat() * 1.03) * 255);
 					// soft noise
 					vColor[0] = vColor[0] ^ (170 + (int)(vRandom.nextFloat() * 80));
 					// xor to image
 					vColor[0] = vColor[0] ^ oldColor[0];
 					vColor[1] = vColor[0];
 					vColor[2] = vColor[0];

 					rstr.setPixel(x, y, vColor);
 				}
 			}
 			return toImageData(image);
 		}
 	}
 }
	/*
	* $Id: SmartLinkLabel.java 5860 2006-05-25 20:29:28 +0000 (Thu, 25 May 2006)
	* eelco12 $ $Revision: 5876 $ $Date: 2006-05-25 20:29:28 +0000 (Thu, 25 May
	* 2006) $
	*
	* ==============================================================================
	* 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 wicket.extensions.markup.html.captcha;

	import java.awt.BasicStroke;
	import java.awt.Color;
	import java.awt.Font;
	import java.awt.Graphics2D;
	import java.awt.Shape;
	import java.awt.font.FontRenderContext;
	import java.awt.font.TextLayout;
	import java.awt.geom.AffineTransform;
	import java.awt.image.BufferedImage;
	import java.awt.image.WritableRaster;
	import java.io.Serializable;
	import java.lang.ref.SoftReference;
	import java.util.ArrayList;
	import java.util.Arrays;
	import java.util.List;
	import java.util.Random;

	import wicket.markup.html.image.resource.DynamicImageResource;
	import wicket.util.time.Time;

	/**
	* Generates a captcha image.
	*
	* @author Joshua Perlow
	*/
	public final class CaptchaImageResource extends DynamicImageResource
	{
	/**
	* This class is used to encapsulate all the filters that a character will
	* get when rendered. The changes are kept so that the size of the shapes
	* can be properly recorded and reproduced later, since it dynamically
	* generates the size of the captcha image. The reason I did it this way is
	* because none of the JFC graphics classes are serializable, so they cannot
	* be instance variables here. If anyone knows a better way to do this,
	* please let me know.
	*/
	private static final class CharAttributes implements Serializable
	{
	private static final long serialVersionUID = 1L;
	private char c;
	private String name;
	private int rise;
	private double rotation;
	private double shearX;
	private double shearY;

	CharAttributes(char c, String name, double rotation, int rise, double shearX, double shearY)
	{
	this.c = c;
	this.name = name;
	this.rotation = rotation;
	this.rise = rise;
	this.shearX = shearX;
	this.shearY = shearY;
	}

	char getChar()
	{
	return c;
	}

	String getName()
	{
	return name;
	}

	int getRise()
	{
	return rise;
	}

	double getRotation()
	{
	return rotation;
	}

	double getShearX()
	{
	return shearX;
	}

	double getShearY()
	{
	return shearY;
	}
	}

	private static final long serialVersionUID = 1L;

	private static int randomInt(int min, int max)
	{
	return (int)(Math.random() * (max - min) + min);
	}

	private static String randomString(int min, int max)
	{
	int num = randomInt(min, max);
	byte b[] = new byte[num];
	for (int i = 0; i < num; i++)
	b[i] = (byte)randomInt('a', 'z');
	return new String(b);
	}

	private String challengeId;
	private final List charAttsList;

	private List fontNames = Arrays.asList(new String[] { "Helventica", "Arial", "Courier" });
	private final int fontSize;
	private final int fontStyle;

	private int height = 0;

	/** Transient image data so that image only needs to be generated once per VM */
	private transient SoftReference imageData;

	private final int margin;

	private int width = 0;

	/**
	* Construct.
	*/
	public CaptchaImageResource()
	{
	this(randomString(6, 8));
	}

	/**
	* Construct.
	*
	* @param challengeId
	* The id of the challenge
	*/
	public CaptchaImageResource(String challengeId)
	{
	this(challengeId, 48, 30);
	}

	/**
	* Construct.
	*
	* @param challengeId
	* The id of the challenge
	* @param fontSize
	* The font size
	* @param margin
	* The image's margin
	*/
	public CaptchaImageResource(String challengeId, int fontSize, int margin)
	{
	this.challengeId = challengeId;
	this.fontStyle = 1;
	this.fontSize = fontSize;
	this.margin = margin;
	this.width = this.margin * 2;
	this.height = this.margin * 2;
	char[] chars = challengeId.toCharArray();
	charAttsList = new ArrayList();
	TextLayout text;
	AffineTransform textAt;
	Shape shape;
	for (int i = 0; i < chars.length; i++)
	{
	String fontName = (String)fontNames.get(randomInt(0, fontNames.size()));
	double rotation = Math.toRadians(randomInt(-35, 35));
	int rise = randomInt(margin / 2, margin);
	Random ran = new Random();
	double shearX = ran.nextDouble() * 0.2;
	double shearY = ran.nextDouble() * 0.2;
	CharAttributes cf = new CharAttributes(chars[i], fontName, rotation, rise, shearX,
	shearY);
	charAttsList.add(cf);
	text = new TextLayout(chars[i] + "", getFont(fontName), new FontRenderContext(null,
	false, false));
	textAt = new AffineTransform();
	textAt.rotate(rotation);
	textAt.shear(shearX, shearY);
	shape = text.getOutline(textAt);
	this.width += (int)shape.getBounds2D().getWidth();
	if (this.height < (int)shape.getBounds2D().getHeight() + rise)
	{
	this.height = (int)shape.getBounds2D().getHeight() + rise;
	}
	}
	}

	/**
	* Gets the id for the challenge.
	*
	* @return The the id for the challenge
	*/
	public final String getChallengeId()
	{
	return challengeId;
	}

	/**
	* Causes the image to be redrawn the next time its requested.
	*
	* @see wicket.Resource#invalidate()
	*/
	public final void invalidate()
	{
	imageData = null;
	}

	/**
	* @see wicket.markup.html.image.resource.DynamicImageResource#getImageData()
	*/
	protected final byte[] getImageData()
	{
	// get image data is always called in sync block
	byte[] data = null;
	if (imageData != null)
	{
	data = (byte[])imageData.get();
	}
	if (data == null)
	{
	data = render();
	imageData = new SoftReference(data);
	setLastModifiedTime(Time.now());
	}
	return data;
	}

	private Font getFont(String fontName)
	{
	return new Font(fontName, fontStyle, fontSize);
	}

	/**
	* Renders this image
	*
	* @return The image data
	*/
	private final byte[] render()
	{
	while (true)
	{
	final BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
	Graphics2D gfx = (Graphics2D)image.getGraphics();
	gfx.setBackground(Color.WHITE);
	int curWidth = margin;
	for (int i = 0; i < charAttsList.size(); i++)
	{
	CharAttributes cf = (CharAttributes)charAttsList.get(i);
	TextLayout text = new TextLayout(cf.getChar() + "", getFont(cf.getName()), gfx
	.getFontRenderContext());
	AffineTransform textAt = new AffineTransform();
	textAt.translate(curWidth, height - cf.getRise());
	textAt.rotate(cf.getRotation());
	textAt.shear(cf.getShearX(), cf.getShearY());
	Shape shape = text.getOutline(textAt);
	curWidth += shape.getBounds().getWidth();
	gfx.setXORMode(Color.BLACK);
	gfx.fill(shape);
	}

	// XOR circle
	int dx = randomInt(width, 2 * width);
	int dy = randomInt(width, 2 * height);
	int x = randomInt(0, width / 2);
	int y = randomInt(0, height / 2);

	gfx.setXORMode(Color.BLACK);
	gfx.setStroke(new BasicStroke(randomInt(fontSize / 8, fontSize / 2)));
	gfx.drawOval(x, y, dx, dy);

	WritableRaster rstr = image.getRaster();
	int[] vColor = new int[3];
	int[] oldColor = new int[3];
	Random vRandom = new Random(System.currentTimeMillis());

	// noise
	for (x = 0; x < width; x++)
	{
	for (y = 0; y < height; y++)
	{
	rstr.getPixel(x, y, oldColor);

	// hard noise
	vColor[0] = 0 + (int)(Math.floor(vRandom.nextFloat() * 1.03) * 255);
	// soft noise
	vColor[0] = vColor[0] ^ (170 + (int)(vRandom.nextFloat() * 80));
	// xor to image
	vColor[0] = vColor[0] ^ oldColor[0];
	vColor[1] = vColor[0];
	vColor[2] = vColor[0];

	rstr.setPixel(x, y, vColor);
	}
	}
	return toImageData(image);
	}
	}
	}