java实现条形码

* * Copyright 2002-2007 Jeremias Maerki or contributors to Barcode4J, as applicable * * 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 com.util;/* * 作者：朱湘鄂 * 目的：达到实现条形码的效果 * 日期：2010-05-24 */import java.awt.image.BufferedImage;import java.io.ByteArrayOutputStream;import java.io.IOException;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import javax.xml.transform.Result;import javax.xml.transform.Source;import javax.xml.transform.Transformer;import javax.xml.transform.TransformerFactory;import org.krysalis.barcode4j.BarcodeGenerator;import org.krysalis.barcode4j.BarcodeUtil;import org.krysalis.barcode4j.output.bitmap.BitmapCanvasProvider;import org.krysalis.barcode4j.output.eps.EPSCanvasProvider;import org.krysalis.barcode4j.output.svg.SVGCanvasProvider;import org.krysalis.barcode4j.tools.MimeTypes;import org.apache.avalon.framework.configuration.Configuration;import org.apache.avalon.framework.configuration.DefaultConfiguration;import org.apache.avalon.framework.logger.ConsoleLogger;import org.apache.avalon.framework.logger.Logger;/** * Simple barcode servlet. * * @version $Id: BarcodeServlet.java,v 1.7 2008/03/04 20:07:23 jmaerki Exp $ */public class BarcodeServlet extends HttpServlet {    /** Parameter name for the message */    public static final String BARCODE_MSG                 = "msg";    /** Parameter name for the barcode type */    public static final String BARCODE_TYPE                = "type";    /** Parameter name for the barcode height */    public static final String BARCODE_HEIGHT              = "height";    /** Parameter name for the module width */    public static final String BARCODE_MODULE_WIDTH        = "mw";    /** Parameter name for the wide factor */    public static final String BARCODE_WIDE_FACTOR         = "wf";    /** Parameter name for the quiet zone */    public static final String BARCODE_QUIET_ZONE          = "qz";    /** Parameter name for the human-readable placement */    public static final String BARCODE_HUMAN_READABLE_POS  = "hrp";    /** Parameter name for the output format */    public static final String BARCODE_FORMAT              = "fmt";    /** Parameter name for the image resolution (for bitmaps) */    public static final String BARCODE_IMAGE_RESOLUTION    = "res";    /** Parameter name for the grayscale or b/w image (for bitmaps) */    public static final String BARCODE_IMAGE_GRAYSCALE     = "gray";    /** Parameter name for the font size of the human readable display */    public static final String BARCODE_HUMAN_READABLE_SIZE = "hrsize";    /** Parameter name for the font name of the human readable display */    public static final String BARCODE_HUMAN_READABLE_FONT = "hrfont";    /** Parameter name for the pattern to format the human readable message */    public static final String BARCODE_HUMAN_READABLE_PATTERN = "hrpattern";    private transient Logger log = new ConsoleLogger(ConsoleLogger.LEVEL_INFO);    /**     * @see javax.servlet.http.HttpServlet#doGet(HttpServletRequest, HttpServletResponse)     */    protected void doGet(HttpServletRequest request, HttpServletResponse response)                throws ServletException, IOException {        try {            String format = determineFormat(request);            int orientation = 0;            Configuration cfg = buildCfg(request);            String msg = request.getParameter(BARCODE_MSG);            if (msg == null) msg = "0123456789";            BarcodeUtil util = BarcodeUtil.getInstance();            BarcodeGenerator gen = util.createBarcodeGenerator(cfg);            ByteArrayOutputStream bout = new ByteArrayOutputStream(4096);            try {                if (format.equals(MimeTypes.MIME_SVG)) {                    //Create Barcode and render it to SVG                    SVGCanvasProvider svg = new SVGCanvasProvider(false, orientation);                    gen.generateBarcode(svg, msg);                    org.w3c.dom.DocumentFragment frag = svg.getDOMFragment();                    //Serialize SVG barcode                    TransformerFactory factory = TransformerFactory.newInstance();                    Transformer trans = factory.newTransformer();                    Source src = new javax.xml.transform.dom.DOMSource(frag);                    Result res = new javax.xml.transform.stream.StreamResult(bout);                    trans.transform(src, res);                } else if (format.equals(MimeTypes.MIME_EPS)) {                    EPSCanvasProvider eps = new EPSCanvasProvider(bout, orientation);                    gen.generateBarcode(eps, msg);                    eps.finish();                } else {                    String resText = request.getParameter(BARCODE_IMAGE_RESOLUTION);                    int resolution = 300; //dpi                    if (resText != null) {                        resolution = Integer.parseInt(resText);                    }                    if (resolution > 2400) {                        throw new IllegalArgumentException(                            "Resolutions above 2400dpi are not allowed");                    }                    if (resolution < 10) {                        throw new IllegalArgumentException(                            "Minimum resolution must be 10dpi");                    }                    String gray = request.getParameter(BARCODE_IMAGE_GRAYSCALE);                    BitmapCanvasProvider bitmap = ("true".equalsIgnoreCase(gray)                        ? new BitmapCanvasProvider(                                bout, format, resolution,                                BufferedImage.TYPE_BYTE_GRAY, true, orientation)                        : new BitmapCanvasProvider(                                bout, format, resolution,                                BufferedImage.TYPE_BYTE_BINARY, false, orientation));                    gen.generateBarcode(bitmap, msg);                    bitmap.finish();                }            } finally {                bout.close();            }            response.setContentType(format);            response.setContentLength(bout.size());            response.getOutputStream().write(bout.toByteArray());            response.getOutputStream().flush();        } catch (Exception e) {            log.error("Error while generating barcode", e);            throw new ServletException(e);        } catch (Throwable t) {            log.error("Error while generating barcode", t);            throw new ServletException(t);        }    }    /**     * Check the request for the desired output format.     * @param request the request to use     * @return MIME type of the desired output format.     */    protected String determineFormat(HttpServletRequest request) {        String format = request.getParameter(BARCODE_FORMAT);        format = MimeTypes.expandFormat(format);        if (format == null) format = MimeTypes.MIME_JPEG;        return format;    }    /**     * Build an Avalon Configuration object from the request.     * @param request the request to use     * @return the newly built COnfiguration object     * @todo Change to bean API     */    protected Configuration buildCfg(HttpServletRequest request) {        DefaultConfiguration cfg = new DefaultConfiguration("barcode");        //Get type        String type = request.getParameter(BARCODE_TYPE);        if (type == null) type = "code128";        DefaultConfiguration child = new DefaultConfiguration(type);        cfg.addChild(child);        //Get additional attributes        DefaultConfiguration attr;        String height = request.getParameter(BARCODE_HEIGHT);        if (height != null) {            attr = new DefaultConfiguration("height");            attr.setValue(height);            child.addChild(attr);        }        String moduleWidth = request.getParameter(BARCODE_MODULE_WIDTH);        if (moduleWidth != null) {            attr = new DefaultConfiguration("module-width");            attr.setValue(moduleWidth);            child.addChild(attr);        }        String wideFactor = request.getParameter(BARCODE_WIDE_FACTOR);        if (wideFactor != null) {            attr = new DefaultConfiguration("wide-factor");            attr.setValue(wideFactor);            child.addChild(attr);        }        String quietZone = request.getParameter(BARCODE_QUIET_ZONE);        if (quietZone != null) {            attr = new DefaultConfiguration("quiet-zone");            if (quietZone.startsWith("disable")) {                attr.setAttribute("enabled", "false");            } else {                attr.setValue(quietZone);            }            child.addChild(attr);        }        // creating human readable configuration according to the new Barcode Element Mappings        // where the human-readable has children for font name, font size, placement and        // custom pattern.        String humanReadablePosition = request.getParameter(BARCODE_HUMAN_READABLE_POS);        String pattern = request.getParameter(BARCODE_HUMAN_READABLE_PATTERN);        String humanReadableSize = request.getParameter(BARCODE_HUMAN_READABLE_SIZE);        String humanReadableFont = request.getParameter(BARCODE_HUMAN_READABLE_FONT);        if (!((humanReadablePosition == null)                && (pattern == null)                && (humanReadableSize == null)                && (humanReadableFont == null))) {            attr = new DefaultConfiguration("human-readable");            DefaultConfiguration subAttr;            if (pattern != null) {                subAttr = new DefaultConfiguration("pattern");                subAttr.setValue(pattern);                attr.addChild(subAttr);            }            if (humanReadableSize != null) {                subAttr = new DefaultConfiguration("font-size");                subAttr.setValue(humanReadableSize);                attr.addChild(subAttr);            }            if (humanReadableFont != null) {                subAttr = new DefaultConfiguration("font-name");                subAttr.setValue(humanReadableFont);                attr.addChild(subAttr);            }            if (humanReadablePosition != null) {              subAttr = new DefaultConfiguration("placement");              subAttr.setValue(humanReadablePosition);              attr.addChild(subAttr);            }            child.addChild(attr);        }        return cfg;    }}  在web.xml中的配置为：  <!-- 条形码的servlet映射和路径 -->  <servlet>  <servlet-name>BarcodeServlet</servlet-name>  <servlet-class>com.util.BarcodeServlet</servlet-class>  </servlet> <servlet-mapping>  <servlet-name>BarcodeServlet</servlet-name>  <url-pattern>/barcode</url-pattern>  </servlet-mapping> 页面的访问：<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%><%String path = request.getContextPath();String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";%><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"><html>  <head>    <base href="<%=basePath%>">        <title>zhuzhu</title> <meta http-equiv="pragma" content="no-cache"> <meta http-equiv="cache-control" content="no-cache"> <meta http-equiv="expires" content="0">     <meta http-equiv="keywords" content="keyword1,keyword2,keyword3"> <meta http-equiv="description" content="This is my page"> <!-- <link rel="stylesheet" type="text/css" href="styles.css"> -->  </head>    <body>    <img src="<%=request.getContextPath() %>/barcode?msg=12345678" height="50px" width=130px/>    </body></html>