承接RC4生成不重复字符串的需求之后，因为优惠码要方便用户使用的缘故，所以思来想去，觉得还是直接生成二维码给用户直接扫比较实用，也不用用户专门记录冗长的优惠码编号。
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所以这一章，就先把java生成二维码【可带logo和文字】做一记录，使用google的工具包zxing
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1.maven依赖
<!-- google提供二维码生成和解析https://mvnrepository.com/artifact/com.google.zxing/core --> <dependency> <groupId>com.google.zxing</groupId> <artifactId>core</artifactId> <version>3.3.2</version> </dependency>
2.完整代码
package testExample; import java.awt.Color; import java.awt.Font; import java.awt.Graphics; import java.awt.image.BufferedImage; import java.io.*; import java.util.HashMap; import java.util.Map; import javax.imageio.ImageIO; import com.google.zxing.*; import com.google.zxing.common.HybridBinarizer; import com.google.zxing.qrcode.QRCodeReader; import lombok.AllArgsConstructor; import lombok.Data; import lombok.NoArgsConstructor; import lombok.experimental.Accessors; import org.springframework.util.StringUtils; import com.google.zxing.common.BitMatrix; import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel; /** * 二维码工具类 * @author SXD * @Date 2018.2.1 * */ public class QR_Code { private static int BLACK = 0x000000; private static int WHITE = 0xFFFFFF; /** * 内部类，设置二维码相关参数 */ @Data(staticConstructor = "of") @NoArgsConstructor @AllArgsConstructor @Accessors(chain = true) public class CodeModel { /** * 正文 */ private String contents; /** * 二维码宽度 */ private int width = 400; /** * 二维码高度 */ private int height = 400; /** * 图片格式 */ private String format = "png"; /** * 编码方式 */ private String character_set = "utf-8"; /** * 字体大小 */ private int fontSize = 12; /** * logo */ private File logoFile; /** * logo所占二维码比例 */ private float logoRatio = 0.20f; /** * 二维码下文字 */ private String desc; private int whiteWidth;//白边的宽度 private int[] bottomStart;//二维码最下边的开始坐标 private int[] bottomEnd;//二维码最下边的结束坐标 } /** * 1.创建最原始的二维码图片 * @param info * @return */ private BufferedImage createCodeImage(CodeModel info){ String contents = StringUtils.isEmpty(info.getContents()) ? "暂无内容" : info.getContents();//获取正文 int width = info.getWidth();//宽度 int height = info.getHeight();//高度 Map<EncodeHintType, Object> hint = new HashMap<>(); hint.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H);//设置二维码的纠错级别【级别分别为M L H Q ，H纠错能力级别最高，约可纠错30%的数据码字】 hint.put(EncodeHintType.CHARACTER_SET, info.getCharacter_set());//设置二维码编码方式【UTF-8】 hint.put(EncodeHintType.MARGIN, 0); MultiFormatWriter writer = new MultiFormatWriter(); BufferedImage img = null; try { //构建二维码图片 //QR_CODE 一种矩阵二维码 BitMatrix bm = writer.encode(contents, BarcodeFormat.QR_CODE, width, height, hint); int[] locationTopLeft = bm.getTopLeftOnBit(); int[] locationBottomRight = bm.getBottomRightOnBit(); info.setBottomStart(new int[]{locationTopLeft[0], locationBottomRight[1]}); info.setBottomEnd(locationBottomRight); int w = bm.getWidth(); int h = bm.getHeight(); img = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB); for(int x=0;x<w;x++){ for(int y=0;y<h;y++){ img.setRGB(x, y, bm.get(x, y) ? BLACK : WHITE); } } } catch (WriterException e) { e.printStackTrace(); } return img; } /** * 2.为二维码增加logo和二维码下文字 * logo--可以为null * 文字--可以为null或者空字符串"" * @param info * @param output */ private void dealLogoAndDesc(CodeModel info, OutputStream output){ //获取原始二维码图片 BufferedImage bm = createCodeImage(info); //获取Logo图片 File logoFile = info.getLogoFile(); int width = bm.getWidth(); int height = bm.getHeight(); Graphics g = bm.getGraphics(); //处理logo if(logoFile!=null && logoFile.exists()){ try{ BufferedImage logoImg = ImageIO.read(logoFile); int logoWidth = logoImg.getWidth(); int logoHeight = logoImg.getHeight(); float ratio = info.getLogoRatio();//获取Logo所占二维码比例大小 if(ratio>0){ logoWidth = logoWidth>width*ratio ? (int)(width*ratio) : logoWidth; logoHeight = logoHeight>height*ratio ? (int)(height*ratio) : logoHeight; } int x = (width-logoWidth)/2; int y = (height-logoHeight)/2; //根据logo 起始位置 和 宽高 在二维码图片上画出logo g.drawImage(logoImg, x, y, logoWidth, logoHeight, null); }catch(Exception e){ e.printStackTrace(); } } //处理二维码下文字 String desc = info.getDesc(); if(!StringUtils.isEmpty(desc)){ try{ //设置文字字体 int whiteWidth = info.getHeight()-info.getBottomEnd()[1]; Font font = new Font("黑体", Font.BOLD, info.getFontSize()); int fontHeight = g.getFontMetrics(font).getHeight(); //计算需要多少行 int lineNum = 1; int currentLineLen = 0; for(int i=0;i<desc.length();i++){ char c = desc.charAt(i); int charWidth = g.getFontMetrics(font).charWidth(c); if(currentLineLen+charWidth>width){ lineNum++; currentLineLen = 0; continue; } currentLineLen += charWidth; } int totalFontHeight = fontHeight*lineNum; int wordTopMargin = 4; BufferedImage bm1 = new BufferedImage(width, height+totalFontHeight+wordTopMargin-whiteWidth, BufferedImage.TYPE_INT_RGB); Graphics g1 = bm1.getGraphics(); if(totalFontHeight+wordTopMargin-whiteWidth>0){ g1.setColor(Color.WHITE); g1.fillRect(0, height, width, totalFontHeight+wordTopMargin-whiteWidth); } g1.setColor(new Color(BLACK)); g1.setFont(font); g1.drawImage(bm, 0, 0, null); width = info.getBottomEnd()[0]-info.getBottomStart()[0]; height = info.getBottomEnd()[1]+1; currentLineLen = 0; int currentLineIndex = 0; int baseLo = g1.getFontMetrics().getAscent(); for(int i=0;i<desc.length();i++){ String c = desc.substring(i, i+1); int charWidth = g.getFontMetrics(font).stringWidth(c); if(currentLineLen+charWidth>width){ currentLineIndex++; currentLineLen = 0; g1.drawString(c, currentLineLen + whiteWidth, height+baseLo+fontHeight*(currentLineIndex)+wordTopMargin); currentLineLen = charWidth; continue; } g1.drawString(c, currentLineLen+whiteWidth, height+baseLo+fontHeight*(currentLineIndex) + wordTopMargin); currentLineLen += charWidth; } g1.dispose(); bm = bm1; }catch(Exception e){ e.printStackTrace(); } } try{ ImageIO.write(bm, StringUtils.isEmpty(info.getFormat()) ? info.getFormat() : info.getFormat(), output); }catch(Exception e){ e.printStackTrace(); } } /** * 3.创建 带logo和文字的二维码 * @param info * @param file */ public void createCodeImage(CodeModel info, File file){ File parent = file.getParentFile(); if(!parent.exists())parent.mkdirs(); OutputStream output = null; try{ output = new BufferedOutputStream(new FileOutputStream(file)); dealLogoAndDesc(info, output); output.flush(); }catch(Exception e){ e.printStackTrace(); }finally{ try { output.close(); } catch (IOException e) { e.printStackTrace(); } } } /** * 3.创建 带logo和文字的二维码 * @param info * @param filePath */ public void createCodeImage(CodeModel info, String filePath){ createCodeImage(info, new File(filePath)); } /** * 4.创建 带logo和文字的二维码 * @param filePath */ public void createCodeImage(String contents,String filePath){ CodeModel codeModel = new CodeModel(); codeModel.setContents(contents); createCodeImage(codeModel, new File(filePath)); } /** * 5.读取 二维码 获取二维码中正文 * @param input * @return */ public String decode(InputStream input){ Map<DecodeHintType, Object> hint = new HashMap<DecodeHintType, Object>(); hint.put(DecodeHintType.POSSIBLE_FORMATS, BarcodeFormat.QR_CODE); String result = ""; try{ BufferedImage img = ImageIO.read(input); int[] pixels = img.getRGB(0, 0, img.getWidth(), img.getHeight(), null, 0, img.getWidth()); LuminanceSource source = new RGBLuminanceSource(img.getWidth(), img.getHeight(), pixels); BinaryBitmap bitmap = new BinaryBitmap(new HybridBinarizer(source)); QRCodeReader reader = new QRCodeReader(); Result r = reader.decode(bitmap, hint); result = r.getText(); }catch(Exception e){ result="读取错误"; } return result; } }
3.测试一下
@Test public void getUUid(){ String ss = RC4.RC4(); System.out.println(ss); QR_Code code = new QR_Code(); // Code.CodeModel codeModel = code.new CodeModel(); // codeModel.setContents(ss); // codeModel.setWidth(400); // codeModel.setHeight(400); // codeModel.setFontSize(15); // codeModel.setLogoFile(new File("G:/ACODE/29936672.jpg")); // codeModel.setDesc("国大金象大药房优惠码"); code.createCodeImage(ss,"G:/ACODE/国大金象大药房.jpg"); }
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方法 选取哪个生成都可以 大同小异 大同小异 没有区别
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最后，如果想封装成jar包供别人调用，参考步骤如下：http://www.cnblogs.com/sxdcgaq8080/p/8399854.html