java实现后台返回base64图形编码

package com.liginfo.app.util; import java.awt.Color; import java.awt.Font; import java.awt.Graphics; import java.awt.Graphics2D; import java.awt.RenderingHints; import java.awt.geom.AffineTransform; import java.awt.image.BufferedImage; import java.io.ByteArrayOutputStream; import java.io.IOException; import java.security.SecureRandom; import java.util.Arrays; import java.util.Random; import javax.imageio.ImageIO; import org.apache.tomcat.util.codec.binary.Base64; import sun.misc.BASE64Encoder; /* * 返回base64验证码的工具类 */ public class RandomGraphic { // 默认验证码6位 private static int DEFAULT_CODE_NUMBERS = 6; private static Random random = new SecureRandom(); public static String generateCode(){ StringBuffer sb = new StringBuffer(); for (int i = 0; i 255) fc = 255; if (bc > 255) bc = 255; int r = fc + random.nextInt(bc - fc); int g = fc + random.nextInt(bc - fc); int b = fc + random.nextInt(bc - fc); return new Color(r, g, b); } private static int getRandomIntColor() { int[] rgb = getRandomRgb(); int color = 0; for (int c : rgb) { color = color << 8; color = color | c; } return color; } private static int[] getRandomRgb() { int[] rgb = new int[3]; for (int i = 0; i <3; i++) { rgb[i] = random.nextInt(255); } return rgb; } private static void shear(Graphics g, int w1, int h1, Color color) { shearX(g, w1, h1, color); shearY(g, w1, h1, color); } private static void shearX(Graphics g, int w1, int h1, Color color) { int period = random.nextInt(2); boolean borderGap = true; int frames = 1; int phase = random.nextInt(2); for (int i = 0; i > 1) * Math.sin((double) i / (double) period + (6.2831853071795862D * (double) phase) / (double) frames); g.copyArea(0, i, w1, 1, (int) d, 0); if (borderGap) { g.setColor(color); g.drawLine((int) d, i, 0, i); g.drawLine((int) d + w1, i, w1, i); } } } private static void shearY(Graphics g, int w1, int h1, Color color) { int period = random.nextInt(40) + 10; // 50; boolean borderGap = true; int frames = 20; int phase = 7; for (int i = 0; i > 1) * Math.sin((double) i / (double) period + (6.2831853071795862D * (double) phase) / (double) frames); g.copyArea(i, 0, 1, h1, 0, (int) d); if (borderGap) { g.setColor(color); g.drawLine(i, (int) d, i, 0); g.drawLine(i, (int) d + h1, i, h1); } } } public  static void main(String arg[]){ for (int i =0;i<2000;i++){ String s = RandomGraphic.generateCode(); System.out.println(s); } } } 

		String code = RandomGraphic.generateVerifyCode(4); String data = ""; try { data = RandomGraphic.outputImage(100,30,code); j.setAttributes(map); } catch (IOException e) { j.setSuccess(false); j.setMsg("获取验证码失败"); // TODO Auto-generated catch block e.printStackTrace(); }