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>