这里有新鲜出炉的Java并发编程示例,程序狗速度看过来!
java 是一种可以撰写跨平台应用软件的面向对象的程序设计语言,是由Sun Microsystems公司于1995年5月推出的Java程序设计语言和Java平台(即JavaEE(j2ee), JavaME(j2me), JavaSE(j2se))的总称。
本文主要介绍用JAVA 设计生成二维码,这里一步一步详细介绍用 java 如何设计二维码,并附有代码示例以便参考,有需要的小伙伴可以参考下
教你一步一步用 java 设计生成二维码
在物联网的时代,二维码是个很重要的东西了,现在无论什么东西都要搞个二维码标志,唯恐落伍,就差人没有用二维码识别了。也许有一天生分证或者户口本都会用二维码识别了。今天心血来潮,看见别人都为自己的博客添加了二维码,我也想搞一个测试一下.
主要用来实现两点:
1. 生成任意文字的二维码.
2. 在二维码的中间加入图像.
一、准备工作。
准备QR二维码3.0 版本的core包和一张jpg图片。
下载QR二维码包。
首先得下载 zxing.jar 包, 我这里用的是3.0 版本的core包
下载地址: 现在已经迁移到了github: https://github.com/zxing/zxing/wiki/Getting-Started-Developing,
当然你也可以从maven仓库下载jar 包: http://central.maven.org/maven2/com/google/zxing/core/
二、程序设计
1、启动eclipse,新建一个java项目,命好项目名(本例取名为QRCodeSoft)。点下一步:
2、导入zxing.jar 包, 我这里用的是3.0 版本的core包:点“添加外部JAR(X)…”。
3、新建两个类,分别是:
BufferedImageLuminanceSource.java
QRCodeUtil.java
关键代码在于:BufferedImageLuminanceSource.java 和QRCodeUtil.java , 其中测试的main 方法位于 QRCodeUtil.java 中。
BufferedImageLuminanceSource.java程序代码:
- package com.yihaomen.barcode;
- import java.awt.Graphics2D;
- import java.awt.geom.AffineTransform;
- import java.awt.image.BufferedImage;
- import com.google.zxing.LuminanceSource;
- public class BufferedImageLuminanceSource extends LuminanceSource {
- private final BufferedImage image;
- private final int left;
- private final int top;
- public BufferedImageLuminanceSource(BufferedImage image) {
- this(image, 0, 0, image.getWidth(), image.getHeight());
- }
- public BufferedImageLuminanceSource(BufferedImage image, int left,
- int top, int width, int height) {
- super(width, height);
- int sourceWidth = image.getWidth();
- int sourceHeight = image.getHeight();
- if (left + width > sourceWidth || top + height > sourceHeight) {
- throw new IllegalArgumentException(
- "Crop rectangle does not fit within image data.");
- }
- for (int y = top; y < top + height; y++) {
- for (int x = left; x < left + width; x++) {
- if ((image.getRGB(x, y) & 0xFF000000) == 0) {
- image.setRGB(x, y, 0xFFFFFFFF); // = white
- }
- }
- }
- this.image = new BufferedImage(sourceWidth, sourceHeight,
- BufferedImage.TYPE_BYTE_GRAY);
- this.image.getGraphics().drawImage(image, 0, 0, null);
- this.left = left;
- this.top = top;
- }
- public byte[] getRow(int y, byte[] row) {
- if (y < 0 || y >= getHeight()) {
- throw new IllegalArgumentException(
- "Requested row is outside the image: " + y);
- }
- int width = getWidth();
- if (row == null || row.length < width) {
- row = new byte[width];
- }
- image.getRaster().getDataElements(left, top + y, width, 1, row);
- return row;
- }
- public byte[] getMatrix() {
- int width = getWidth();
- int height = getHeight();
- int area = width * height;
- byte[] matrix = new byte[area];
- image.getRaster().getDataElements(left, top, width, height, matrix);
- return matrix;
- }
- public boolean isCropSupported() {
- return true;
- }
- public LuminanceSource crop(int left, int top, int width, int height) {
- return new BufferedImageLuminanceSource(image, this.left + left,
- this.top + top, width, height);
- }
- public boolean isRotateSupported() {
- return true;
- }
- public LuminanceSource rotateCounterClockwise() {
- int sourceWidth = image.getWidth();
- int sourceHeight = image.getHeight();
- AffineTransform transform = new AffineTransform(0.0, -1.0, 1.0,
- 0.0, 0.0, sourceWidth);
- BufferedImage rotatedImage = new BufferedImage(sourceHeight,
- sourceWidth, BufferedImage.TYPE_BYTE_GRAY);
- Graphics2D g = rotatedImage.createGraphics();
- g.drawImage(image, transform, null);
- g.dispose();
- int width = getWidth();
- return new BufferedImageLuminanceSource(rotatedImage, top,
- sourceWidth - (left + width), getHeight(), width);
- }
- }
QRCodeUtil.java的程序代码:
- package com.yihaomen.barcode;
- import java.awt.BasicStroke;
- import java.awt.Graphics;
- import java.awt.Graphics2D;
- import java.awt.Image;
- import java.awt.Shape;
- import java.awt.geom.RoundRectangle2D;
- import java.awt.image.BufferedImage;
- import java.io.File;
- import java.io.OutputStream;
- import java.util.Hashtable;
- import java.util.Random;
- import javax.imageio.ImageIO;
- import com.google.zxing.BarcodeFormat;
- import com.google.zxing.BinaryBitmap;
- import com.google.zxing.DecodeHintType;
- import com.google.zxing.EncodeHintType;
- import com.google.zxing.MultiFormatReader;
- import com.google.zxing.MultiFormatWriter;
- import com.google.zxing.Result;
- import com.google.zxing.common.BitMatrix;
- import com.google.zxing.common.HybridBinarizer;
- import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;
- /**
- * 二维码工具类
- *
- */
- public class QRCodeUtil {
- private static final String CHARSET = "utf-8";
- private static final String FORMAT_NAME = "JPG";
- // 二维码尺寸
- private static final int QRCODE_SIZE = 300;
- // LOGO宽度
- private static final int WIDTH = 60;
- // LOGO高度
- private static final int HEIGHT = 60;
- private static BufferedImage createImage(String content, String imgPath, boolean needCompress) throws Exception {
- Hashtable < EncodeHintType,
- Object > hints = new Hashtable < EncodeHintType,
- Object > ();
- hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H);
- hints.put(EncodeHintType.CHARACTER_SET, CHARSET);
- hints.put(EncodeHintType.MARGIN, 1);
- BitMatrix bitMatrix = new MultiFormatWriter().encode(content, BarcodeFormat.QR_CODE, QRCODE_SIZE, QRCODE_SIZE, hints);
- int width = bitMatrix.getWidth();
- int height = bitMatrix.getHeight();
- BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
- for (int x = 0; x < width; x++) {
- for (int y = 0; y < height; y++) {
- image.setRGB(x, y, bitMatrix.get(x, y) ? 0xFF000000: 0xFFFFFFFF);
- }
- }
- if (imgPath == null || "".equals(imgPath)) {
- return image;
- }
- // 插入图片
- QRCodeUtil.insertImage(image, imgPath, needCompress);
- return image;
- }
- /**
- * 插入LOGO
- *
- * @param source
- * 二维码图片
- * @param imgPath
- * LOGO图片地址
- * @param needCompress
- * 是否压缩
- * @throws Exception
- */
- private static void insertImage(BufferedImage source, String imgPath, boolean needCompress) throws Exception {
- File file = new File(imgPath);
- if (!file.exists()) {
- System.err.println("" + imgPath + " 该文件不存在!");
- return;
- }
- Image src = ImageIO.read(new File(imgPath));
- int width = src.getWidth(null);
- int height = src.getHeight(null);
- if (needCompress) { // 压缩LOGO
- if (width > WIDTH) {
- width = WIDTH;
- }
- if (height > HEIGHT) {
- height = HEIGHT;
- }
- Image image = src.getScaledInstance(width, height, Image.SCALE_SMOOTH);
- BufferedImage tag = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
- Graphics g = tag.getGraphics();
- g.drawImage(image, 0, 0, null); // 绘制缩小后的图
- g.dispose();
- src = image;
- }
- // 插入LOGO
- Graphics2D graph = source.createGraphics();
- int x = (QRCODE_SIZE - width) / 2;
- int y = (QRCODE_SIZE - height) / 2;
- graph.drawImage(src, x, y, width, height, null);
- Shape shape = new RoundRectangle2D.Float(x, y, width, width, 6, 6);
- graph.setStroke(new BasicStroke(3f));
- graph.draw(shape);
- graph.dispose();
- }
- /**
- * 生成二维码(内嵌LOGO)
- *
- * @param content
- * 内容
- * @param imgPath
- * LOGO地址
- * @param destPath
- * 存放目录
- * @param needCompress
- * 是否压缩LOGO
- * @throws Exception
- */
- public static void encode(String content, String imgPath, String destPath, boolean needCompress) throws Exception {
- BufferedImage image = QRCodeUtil.createImage(content, imgPath, needCompress);
- mkdirs(destPath);
- String file = new Random().nextInt(99999999) + ".jpg";
- ImageIO.write(image, FORMAT_NAME, new File(destPath + "/" + file));
- }
- /**
- * 当文件夹不存在时,mkdirs会自动创建多层目录,区别于mkdir.(mkdir如果父目录不存在则会抛出异常)
- * @author lanyuan
- * Email: mmm333zzz520@163.com
- * @date 2013-12-11 上午10:16:36
- * @param destPath 存放目录
- */
- public static void mkdirs(String destPath) {
- File file = new File(destPath);
- //当文件夹不存在时,mkdirs会自动创建多层目录,区别于mkdir.(mkdir如果父目录不存在则会抛出异常)
- if (!file.exists() && !file.isDirectory()) {
- file.mkdirs();
- }
- }
- /**
- * 生成二维码(内嵌LOGO)
- *
- * @param content
- * 内容
- * @param imgPath
- * LOGO地址
- * @param destPath
- * 存储地址
- * @throws Exception
- */
- public static void encode(String content, String imgPath, String destPath) throws Exception {
- QRCodeUtil.encode(content, imgPath, destPath, false);
- }
- /**
- * 生成二维码
- *
- * @param content
- * 内容
- * @param destPath
- * 存储地址
- * @param needCompress
- * 是否压缩LOGO
- * @throws Exception
- */
- public static void encode(String content, String destPath, boolean needCompress) throws Exception {
- QRCodeUtil.encode(content, null, destPath, needCompress);
- }
- /**
- * 生成二维码
- *
- * @param content
- * 内容
- * @param destPath
- * 存储地址
- * @throws Exception
- */
- public static void encode(String content, String destPath) throws Exception {
- QRCodeUtil.encode(content, null, destPath, false);
- }
- /**
- * 生成二维码(内嵌LOGO)
- *
- * @param content
- * 内容
- * @param imgPath
- * LOGO地址
- * @param output
- * 输出流
- * @param needCompress
- * 是否压缩LOGO
- * @throws Exception
- */
- public static void encode(String content, String imgPath, OutputStream output, boolean needCompress) throws Exception {
- BufferedImage image = QRCodeUtil.createImage(content, imgPath, needCompress);
- ImageIO.write(image, FORMAT_NAME, output);
- }
- /**
- * 生成二维码
- *
- * @param content
- * 内容
- * @param output
- * 输出流
- * @throws Exception
- */
- public static void encode(String content, OutputStream output) throws Exception {
- QRCodeUtil.encode(content, null, output, false);
- }
- /**
- * 解析二维码
- *
- * @param file
- * 二维码图片
- * @return
- * @throws Exception
- */
- public static String decode(File file) throws Exception {
- BufferedImage image;
- image = ImageIO.read(file);
- if (image == null) {
- return null;
- }
- BufferedImageLuminanceSource source = new BufferedImageLuminanceSource(image);
- BinaryBitmap bitmap = new BinaryBitmap(new HybridBinarizer(source));
- Result result;
- Hashtable < DecodeHintType,
- Object > hints = new Hashtable < DecodeHintType,
- Object > ();
- hints.put(DecodeHintType.CHARACTER_SET, CHARSET);
- result = new MultiFormatReader().decode(bitmap, hints);
- String resultStr = result.getText();
- return resultStr;
- }
- /**
- * 解析二维码
- *
- * @param path
- * 二维码图片地址
- * @return
- * @throws Exception
- */
- public static String decode(String path) throws Exception {
- return QRCodeUtil.decode(new File(path));
- }
- public static void main(String[] args) throws Exception {
- String text = "http://www.yihaomen.com";
- QRCodeUtil.encode(text, "c:/me.jpg", "c:/barcode", true);
- }
- }
生成不带logo 的二维码
程序代码如下:
- public static void main(String[] args) throws Exception {
- String text = "http://www.dans88.com.cn";
- QRCodeUtil.encode(text, "", "d:/MyWorkDoc", true);
- }
运行这个测试方法,生成的二维码不带 logo , 样式如下:
有兴趣可以用手机扫描一下
生成带logo 的二维码
logo 可以用自己的头像,或者自己喜欢的一个图片都可以 , 采用如下代码,程序代码如下:
- public static void main(String[] args) throws Exception {
- String text = "http://www.dans88.com.cn";
- QRCodeUtil.encode(text, "d:/MyWorkDoc/my180.jpg", "d:/MyWorkDoc", true);
- }
唯一的区别是,在前面的基础上指定了logo 的地址,这里测试都用了c盘的图片文件
用手机扫描,能出现要出现的文字,点击就进入自己的网站。
来源: http://www.phperz.com/article/17/1121/360283.html