一、先寫一個驗證碼工具類別
package com.yx.cus.util;import java.awt.BasicStroke;import java.awt.Color;import java.awt.Font;import java.awt.Graphics2D;import java.awt.image.BufferedImage;import java.io.IOException;import java.io.OutputStream;import java.util.Random;import javax.imageio.ImageIO;public class VerifyCode {
private int w = 70; private int h = 35; private Random r = new Random(); // {"宋体", "华文楷体", "黑体", "华文新魏", "华文隶书", "微软雅黑", "楷体_GB2312"}
private String[] fontNames = {"宋体", "华文楷体", "黑体", "微软雅黑", "楷体_GB2312"}; private String codes = "23456789abcdefghjkmnopqrstuvwxyzABCDEFGHJKMNPQRSTUVWXYZ"; private Color bgColor = new Color(255, 255, 255); public static String text ; private Color randomColor () { int red = r.nextInt(150); int green = r.nextInt(150); int blue = r.nextInt(150); return new Color(red, green, blue);
} private Font randomFont () { int index = r.nextInt(fontNames.length);
String fontName = fontNames[index]; int style = r.nextInt(4); int size = r.nextInt(5) + 24;
return new Font(fontName, style, size);//指定字体名称、样式和点大小，创建一个新 Font。
} //画干扰的线条
private void drawLine (BufferedImage image) { int num = 3;//画三条
Graphics2D g2 = (Graphics2D)image.getGraphics(); for(int i = 0; i < num; i++) { int x1 = r.nextInt(w); int y1 = r.nextInt(h); int x2 = r.nextInt(w); int y2 = r.nextInt(h);
g2.setStroke(new BasicStroke(1.5F));
g2.setColor(Color.BLUE);
g2.drawLine(x1, y1, x2, y2);
}
} private char randomChar () { int index = r.nextInt(codes.length()); return codes.charAt(index);
} private BufferedImage createImage () {
BufferedImage image = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);
Graphics2D g2 = (Graphics2D)image.getGraphics();
g2.setColor(this.bgColor);
g2.fillRect(0, 0, w, h); return image;
} public BufferedImage getImage () {
BufferedImage image = createImage();
Graphics2D g2 = (Graphics2D)image.getGraphics();
StringBuilder sb = new StringBuilder(); // 向图片中画4个字符
for(int i = 0; i < 4; i++) {
String s = randomChar() + "";
sb.append(s);
float x = i * 1.0F * w / 4;
g2.setFont(randomFont());
g2.setColor(randomColor());
/**
* 首字符的基线位于用户空间的 (x, h-5) 位置处
* 原点在左上角,X轴递增的方向是从左向右;Y轴是从上到下
* 在提供的坐标位于基线上最左边字符的情况下，可以从右到左呈现字形
* h-5表示y轴方向,向上偏移了5
*/
g2.drawString(s, x, h-5);
} this.text = sb.toString();
drawLine(image);
return image;
} public String getText () { return text;
} public static void output (BufferedImage image, OutputStream out)
throws IOException {
ImageIO.write(image, "JPEG", out);
}
}這個工具類別我們主要使用兩個方法：
1.透過getImage()方法製作驗證碼，回傳BufferedImage 類型的驗證碼
2.透過getText()方法取得驗證碼的文本，傳回String類型
二。驗證碼的介面（controller）
/**
* 验证码
* @param request
* @return
* @throws Exception
*/@RequestMapping(value = "/VC", method = RequestMethod.POST)@ResponseBodypublic void VC(HttpServletRequest request, HttpServletResponse response ) throws Exception{
VerifyCode code=new VerifyCode();
BufferedImage image = code.getImage(); //将验证码文本存到Redis
vckey=IDUtil.nextId();
JedisClient.set(vckey, code.getText(),60);
ImageIO.write(image,"jpg",response.getOutputStream());
}該介面會傳回前端一個驗證碼，是以流的形式返回的，在返回之前會產生一個唯一的標識賦給一個全域變量，用來在redis裡存入該驗證碼的文本，以作後用，存入的文本有時間限制
三、獲取驗證碼文本標識的接口（就是存入驗證碼文本的值）
/**
* 验证码文本的标识
* @param request
* @return
* @throws Exception
*/
@RequestMapping(value = "/VCkey", method = RequestMethod.POST)@ResponseBodypublic String VCkey(HttpServletRequest request, HttpServletResponse response ) throws Exception{
System.out.println(vckey); return vckey;
}#這個介面主要就是把在redis裡存驗證碼文字的鍵回傳給前端，然後在登入的時候一起傳回登入的介面
四、登入介面（試例）
String user_phone = reqstr.get("user_phone");//账号String user_pwd = reqstr.get("user_pwd");//密码String vc = reqstr.get("vc").toLowerCase();//用户输入的验证码String vckey = reqstr.get("vckey");//前端获取的验证码文本的键（标识）String vcode= (String)JedisClient.get(vckey);//通过标识从redis里获取验证码文本if(vc.equals(vcode.toLowerCase())) {//用户输入的验证码与redsi存的作比较
“验证码成功”
}else if（vcode==null）{
“验证码以过期”
}else{
“验证码错误”
}補充：驗證碼的鍵（標識）也可以在前端產生,比如產生一個時間戳，在請求驗證碼的接口時作為參數傳入，這樣後台就可以少寫一個接口和全局變量
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