servlet to generate QRcode png according to chart.googleapis.com/chart

common/src/main/java/org/phoenixctms/ctsms/util/CommonUtil.java

@@ -256,6 +256,8 @@ public final void remove() {
 	private static final String HEX_DIGITS = "0123456789ABCDEF";
 	public final static String GIF_FILENAME_EXTENSION = "gif";
 	public static final String GIF_MIMETYPE_STRING = "image/gif";
+	public static final String PNG_FILENAME_EXTENSION = "png";
+	public static final String PNG_MIMETYPE_STRING = "image/png";
 	public static final String HTML_MIMETYPE_STRING = "text/html";
 	public static final String BEACON_PATH = "beacon";
 	public static final String UNSUBSCRIBE_PATH = "unsubscribe";

web/src/main/java/org/phoenixctms/ctsms/web/servlet/QRCodeServlet.java

@@ -0,0 +1,119 @@
+package org.phoenixctms.ctsms.web.servlet;
+
+import java.awt.Color;
+import java.awt.Graphics2D;
+import java.awt.image.BufferedImage;
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.Hashtable;
+
+import javax.imageio.ImageIO;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+
+import org.phoenixctms.ctsms.util.CommonUtil;
+import org.phoenixctms.ctsms.web.util.GetParamNames;
+
+import com.google.zxing.BarcodeFormat;
+import com.google.zxing.EncodeHintType;
+import com.google.zxing.common.BitMatrix;
+import com.google.zxing.qrcode.QRCodeWriter;
+import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;
+
+public class QRCodeServlet extends FileServletBase {
+
+	private final static ErrorCorrectionLevel DEFAULT_ERROR_CORRECTION_LEVEL = ErrorCorrectionLevel.L;
+	private final static int DEFAULT_WIDTH = 100;
+	private final static int DEFAULT_HEIGHT = 100;
+	private final static int DEFAULT_MARGIN = 4;
+	private final static String FILE_NAME = "qrcode." + CommonUtil.PNG_FILENAME_EXTENSION;
+
+	@Override
+	protected FileStream createFileStream(HttpServletRequest request, HttpServletResponse response) throws IOException {
+		ErrorCorrectionLevel errorCorrectionLevel = DEFAULT_ERROR_CORRECTION_LEVEL;
+		int margin = DEFAULT_MARGIN;
+		try {
+			String labelData[] = request.getParameter(GetParamNames.QR_CODE_CHLD.toString()).trim().split("\\s*\\|\\s*", 2);
+			errorCorrectionLevel = ErrorCorrectionLevel.valueOf(labelData[0]);
+			margin = Integer.parseInt(labelData[1]);
+		} catch (Exception e) {
+		}
+		int width = DEFAULT_WIDTH;
+		int height = DEFAULT_HEIGHT;
+		try {
+			String size[] = request.getParameter(GetParamNames.QR_CODE_CHS.toString()).trim().split("\\s*x\\s*", 2);
+			width = Integer.parseInt(size[0]);
+			height = Integer.parseInt(size[1]);
+		} catch (Exception e) {
+		}
+		String text = request.getParameter(GetParamNames.QR_CODE_CHL.toString());
+		final byte[] data;
+		final Long fileSize;
+		if (!CommonUtil.isEmptyString(text)) {
+			Hashtable<EncodeHintType, Object> hintMap = new Hashtable<>();
+			//hintMap.put(EncodeHintType.CHARACTER_SET, "UTF-8");
+			hintMap.put(EncodeHintType.ERROR_CORRECTION, errorCorrectionLevel);
+			hintMap.put(EncodeHintType.MARGIN, margin);
+			QRCodeWriter qrCodeWriter = new QRCodeWriter();
+			BitMatrix byteMatrix = null;
+			try {
+				byteMatrix = qrCodeWriter.encode(text, BarcodeFormat.QR_CODE, width, height, hintMap);
+			} catch (Exception e) {
+			}
+			if (byteMatrix != null) {
+				BufferedImage image = new BufferedImage(byteMatrix.getWidth(), byteMatrix.getHeight(), BufferedImage.TYPE_INT_RGB);
+				image.createGraphics();
+				Graphics2D graphics = (Graphics2D) image.getGraphics();
+				graphics.setColor(Color.WHITE);
+				graphics.fillRect(0, 0, byteMatrix.getWidth(), byteMatrix.getHeight());
+				graphics.setColor(Color.BLACK);
+				for (int i = 0; i < byteMatrix.getWidth(); i++) {
+					for (int j = 0; j < byteMatrix.getHeight(); j++) {
+						if (byteMatrix.get(i, j)) {
+							graphics.fillRect(i, j, 1, 1);
+						}
+					}
+				}
+				ByteArrayOutputStream baos = new ByteArrayOutputStream();
+				ImageIO.write(image, CommonUtil.PNG_FILENAME_EXTENSION, baos);
+				data = baos.toByteArray();
+				fileSize = (long) data.length;
+			} else {
+				data = null;
+				fileSize = null;
+			}
+		} else {
+			data = null;
+			fileSize = null;
+		}
+		return new FileStream() {
+
+			@Override
+			public String getFileName() {
+				return FILE_NAME;
+			}
+
+			@Override
+			public Long getFileSize() {
+				return fileSize;
+			}
+
+			@Override
+			public String getMimeType() {
+				return CommonUtil.PNG_MIMETYPE_STRING;
+			}
+
+			@Override
+			public InputStream getStream() {
+				return new ByteArrayInputStream(data);
+			}
+
+			@Override
+			public boolean isNotFound() {
+				return data == null;
+			}
+		};
+	}
+}

web/src/main/java/org/phoenixctms/ctsms/web/util/GetParamNames.java

@@ -76,7 +76,10 @@ public enum GetParamNames {
 	REFERER("referer"),
 	UUID("uuid"),
 	VALIDATE("validate"),
-	BEACON("beacon");
+	BEACON("beacon"),
+	QR_CODE_CHLD("chld"),
+	QR_CODE_CHS("chs"),
+	QR_CODE_CHL("chl");
 
 	private final String value;
 

web/src/main/webapp/WEB-INF/web.xml

@@ -162,6 +162,11 @@
 		<servlet-class>org.phoenixctms.ctsms.web.servlet.UnsubscribeServlet</servlet-class>
 		<load-on-startup>3</load-on-startup>
 	</servlet>
+	<servlet>
+		<servlet-name>qrCodeServlet</servlet-name>
+		<servlet-class>org.phoenixctms.ctsms.web.servlet.QRCodeServlet</servlet-class>
+		<load-on-startup>4</load-on-startup>
+	</servlet>
 	<!-- overlapping mappings -->
 	<!-- http://www.roguewave.com/portals/0/products/hydraexpress/docs/3.5.0/html/rwsfservletug/4-3.html -->
 	<servlet-mapping>
@@ -180,6 +185,10 @@
 		<servlet-name>unsubscribeServlet</servlet-name>
 		<url-pattern>/unsubscribe/*</url-pattern>
 	</servlet-mapping>
+	<servlet-mapping>
+		<servlet-name>qrCodeServlet</servlet-name>
+		<url-pattern>/chart</url-pattern>
+	</servlet-mapping>	
 	<context-param>
 		<param-name>javax.faces.VALIDATE_EMPTY_FIELDS</param-name>
 		<param-value>true</param-value>