将图片转成base64字符串并在JSP页面显示的Java代码
本事例主要讲了如下几点:
1:将图片转换为BASE64加密字符串.
2:将图片流转换为BASE64加密字符串.
3:将BASE64加密字符串转换为图片.
* 4:在jsp文件中以引用的方式和BASE64加密字符串方式展示图片.
首先看工具类:
import java.awt.image.BufferedImage; import java.io.ByteArrayInputStream; import java.io.ByteArrayOutputStream; import java.io.File; import java.io.IOException; import java.io.InputStream; import javax.imageio.ImageIO; import sun.misc.BASE64Decoder; import sun.misc.BASE64Encoder; /** * @author IluckySi * @since 20150122 */ public class ImageUtil { private static BASE64Encoder encoder = new sun.misc.BASE64Encoder(); private static BASE64Decoder decoder = new sun.misc.BASE64Decoder(); /** * 将图片转换为BASE64加密字符串. * @param imagePath 图片路径. * @param format 图片格式. * @return */ public String convertImageToByte(String imagePath, String format) { File file = new File(imagePath); BufferedImage bi = null; ByteArrayOutputStream baos = null; String result = null; try { bi = ImageIO.read(file); baos = new ByteArrayOutputStream(); ImageIO.write(bi, format == null ? "jpg" : format, baos); byte[] bytes = baos.toByteArray(); result = encoder.encodeBuffer(bytes).trim(); System.out.println("将图片转换为BASE64加密字符串成功！"); } catch (IOException e) { System.out.println("将图片转换为 BASE64加密字符串失败: " + e); } finally { try { if(baos != null) { baos.close(); baos = null; } } catch (Exception e) { System.out.println("关闭文件流发生异常: " + e); } } return result; } /** * 将图片流转换为BASE64加密字符串. * @param imageInputStream * @param format 图片格式. * @return */ public String convertImageStreamToByte(InputStream imageInputStream, String format) { BufferedImage bi = null; ByteArrayOutputStream baos = null; String result = null; try { bi = ImageIO.read(imageInputStream); baos = new ByteArrayOutputStream(); ImageIO.write(bi, format == null ? "jpg" : format, baos); byte[] bytes = baos.toByteArray(); result = encoder.encodeBuffer(bytes).trim(); System.out.println("将图片流转换为BASE64加密字符串成功！"); } catch (IOException e) { System.out.println("将图片流转换为 BASE64加密字符串失败: " + e); } finally { try { if(baos != null) { baos.close(); baos = null; } } catch (Exception e) { System.out.println("关闭文件流发生异常: " + e); } } return result; } /** * 将BASE64加密字符串转换为图片. * @param base64String * @param imagePath 图片生成路径. * @param format 图片格式. */ public void convertByteToImage(String base64String, String imagePath, String format) { byte[] bytes = null; ByteArrayInputStream bais = null; BufferedImage bi = null; File file = null; try { bytes = decoder.decodeBuffer(base64String); bais = new ByteArrayInputStream(bytes); bi = ImageIO.read(bais); file = new File(imagePath); ImageIO.write(bi, format == null ? "jpg" : format, file); System.out.println("将BASE64加密字符串转换为图片成功！"); } catch (IOException e) { System.out.println("将BASE64加密字符串转换为图片失败: " + e); } finally { try { if(bais != null) { bais.close(); bais = null; } } catch (Exception e) { System.out.println("关闭文件流发生异常: " + e); } } } } 然后看测试类：
import java.io.InputStream; import com.ilucky.util.image.ImageUtil; /** * 本事例主要讲了如下几点: * 1:将图片转换为BASE64加密字符串. * 2:将图片流转换为BASE64加密字符串. * 3:将BASE64加密字符串转换为图片. * 4:在jsp文件中以引用的方式和BASE64加密字符串方式展示图片. * @author IluckySi * @since 20150122 */ public class MainTest { public static void main(String[] args) { ImageUtil imageUtil = new ImageUtil(); String base64String = imageUtil.convertImageToByte("D:\\test.png", "png"); System.out.println(base64String); imageUtil.convertByteToImage(base64String, "D:\\test2.png", "png"); InputStream is = MainTest.class.getResourceAsStream("test.png"); String base64String2 = imageUtil.convertImageStreamToByte(is, "png"); System.out.println(base64String2); imageUtil.convertByteToImage(base64String2, "D:\\test3.png", "png"); } } 最后看jsp文件:
<!DOCTYPE html> <html> <head> <title>index.html</title> <meta http-equiv="keywords" content="keyword1,keyword2,keyword3"> <meta http-equiv="description" content="this is my page"> <meta http-equiv="content-type" content="text/html; charset=UTF-8"> </head> <body> <!-- data表示取得数据的协定名称,image/png是数据类型名称,base64 是数据的编码方法, 逗号后面是image/png文件base64编码后的数据. data:text/css;base64,base64编码的CSS代码 data:text/javascript,Javascript代码 data:text/javascript;base64,base64编码的Javascript代码 data:image/gif;base64,base64编码的gif图片数据 data:image/png;base64,base64编码的png图片数据 data:image/jpeg;base64,base64编码的jpeg图片数据 data:image/x-icon;base64,base64编码的icon图片数据 --> <img src="test.png"/> <img src="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAACAAAAAgCAYAAABzenr0AAAFYklEQVR42sVXfUyUdRz/8XKhMZQO 7nmeuwMFwrBEVJqgDOcUHZvNuTarrdKam0zdKrckAy4goowxbaM5hE1yjVVzLjLRokBFz2qsQPGF F8vmamtkL4s4OHDy6ff5EQcXx91hf/jHB777fj8v3+d57p7nOQFA3EuoPxcLhV90SlxziOSeUrHd WRz5fv1uc1fl03OGizdGgmBd/5K5mzNyyO0M4EkEXqBAiI58Ed9WEFp1+MXYm1vW68hKM7AwJR5W mx3RZqsCa/Y4I4dcaqilx10t0PGqCOssEjuvH7H9vW1zEgzNgK5ZYVh02HUN86w65tvGwJo9zhRH cqmhlh70mtEC7a8Ie2ep6dPfW5eM3OnbhMo9S6GbLV6h04Eccqmhlh70omdQC3TsFbbLZaYL/W2Z wA+PYbQ9B780rUJu1nxoMZaAC5BDLjXU0oNe9KS33wXkqRKXXguv+as1HejOxYhzNdwS+G4NjlUs U0cX7+cscEYOudRQSw960ZPezPC9QIE69dv6Pk4exLX1GDm/Cu5z2Qojzmy4WrOxZUOSPELNz9Fr ikMuNR699KInvZkx/sH0WqB9rzCuH5j7Mzrk1uel8HQW3GcmgK+y4axOR0qCVX7gpoazxxk55E7W 0oue9GYGs7wXKFCnP7+/cdEovs7GUHMm3C0rvHD7jMTZFSjYugAW89RvAXuckUPuf/X0pDczmMVM zwJyI8v3lVFX7pzLxMiXGXB/sdwncDoDvfXLkJFqh1WbuBSs2eOMnOn09GYGs5g5eYHcXw/HAWcz MfRZOtwSQz7APloexcHdD0GLnVhAlzV7nPnT8j8zmMVMzwKdjtCy/qPJuN0kSY1L/OL250tw61ga Nqy0Q7doCqzZ4yygXmYwi5meBa6Wmk4NNaRgpDEVQ8cX+YVbAk2L0VCcrL52BGv23AG0hMqQWcz0 LNBTHtGFkw9D4UQQkLxR+X/LujiF0RMz0xIqc3yBb4sifmp+80G0lCcFhWYJZ0USDu6ar8C6OUit 0sssZnoWaNhh+tFqGIg3dM9p9QvJM5t1vP1cvALrmWiZxUzPAidfMLWlJBjqZhKMiRarY+UiAzer 5ymwZi8Y7dgNywAzPQuc3xNet3Ypv8+Bn3Y0sUqTQ3k24MM4BdZW3f9zYuKeoYNZzPQscNkRsv35 1WbExhoBDXT5zN+4XMcfNVYMv2dTYM0eZ4H0zGAWMz0L9JaK1P1PRQ7EWa0Bn3aJdh2NL2vAEQ2u 2jGwZo+zQHq7zJBZrusyc9IZEOEX8sM/yFxokafI8LO9jrx1GgaqY+CujYHr0BhYs5eXoynO9Kff ADOc+eEfyUyT19Owp0SsKd0U5eYrlU+xvMaLk3S0OcxAbTRcB73BHmdpSWNcn5dPejNDZq2d8jiW G4W07Q39JCctVr3T+br2ZY+bcac6CoPvzoGryhvscUaOr88CPenNDGb5fCPqKha2o3kRF1MTKfA+ +uxHNNx4IwrDVZFwveMbnJFD7uSzQC960psZft8Je4rFkzXPzh5eME+HTTfUs94mbxx1W+cCVbMw uH82XNOAM3LIpUZppQe96EnvoN6K5TXaVfPMbCxO1BAVbeCJzBj89tYsDO+/DwOVEX5BDrmbpYZa etCLnkG/ll8qEqK7WOQe32lybs54AKd23I/RA+EYqDAFBXJPSg219KAXPWf8y+iKQxhXHaLyRklI 363yUAzsC8OghGtfqE9wRg651FBLj7v/aTb+ul4oUi4VipIuh+i+WSKG+spC8Gd5CPr/BWv2OJOc Hsl9XWoW/v/fht5LhLUXiARZb71cJOquFIlv5BH2EqzZ40xyEsm9OJMfp/cS/wC6xRqbyM2GFQAA AABJRU5ErkJggg=="/> </body> </html>
部署项目，启动服务器,访问jsp页面,会看到浏览器上有两张一样的图片.