public static String encodeToBase64(String content){
MultiFormatWriter multiFormatWriter = new MultiFormatWriter();
Map hints = new HashMap();
hints.put(EncodeHintType.CHARACTER_SET, "UTF-8"); //设置字符集编码类型
BitMatrix bitMatrix = null;
try {
bitMatrix = multiFormatWriter.encode(content, BarcodeFormat.QR_CODE, 300, 300,hints);
BufferedImage image = toBufferedImage(bitMatrix);
ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
//输出二维码图片流
try {
ImageIO.write(image, "png",outputStream);
return Base64.encodeBase64String(outputStream.toByteArray());
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
} catch (WriterException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
return null;
}
基础转换
public void putImage(String key, Image image) throws IOException {
// Image->bufferreImage
BufferedImage bimg = new BufferedImage(image.getWidth(null),
image.getHeight(null), BufferedImage.TYPE_INT_RGB);
Graphics g = bimg.createGraphics();
g.drawImage(image, 0, 0, null);
g.dispose();
// bufferImage->base64
ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
ImageIO.write(bimg, "jpg", outputStream);
BASE64Encoder encoder = new BASE64Encoder();
String base64Img = encoder.encode(outputStream.toByteArray());
// 输出
this.content = this.content.replace("@{" + key + "}",
"<img src= \"data:image/png;base64," + base64Img + "\"/>");
}
public void putImage(String key, Image image, int width, int height)
throws IOException {
// Image->bufferreImage
BufferedImage bimg = new BufferedImage(image.getWidth(null),
image.getHeight(null), BufferedImage.TYPE_INT_RGB);
Graphics g = bimg.createGraphics();
g.drawImage(image, 0, 0, null);
g.dispose();
// bufferImage->base64
ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
ImageIO.write(bimg, "jpg", outputStream);
BASE64Encoder encoder = new BASE64Encoder();
String base64Img = encoder.encode(outputStream.toByteArray());
this.content = this.content.replace("@{" + key + "}",
"<img src= \"data:image/png;base64," + base64Img
+ "\" width=\"" + width + "\" height=\"" + height
+ "\"/>");
}
原文地址：https://www.cnblogs.com/yxw699/p/9298262.html