java数字和中文算数验证码
效果图
本文代码 https://gitee.com/tothis/java-record/tree/master/src/main/java/com/example/captcha
- 中文实现参考 https://gitee.com/whvse/EasyCaptcha.git
- 数字实现参考 https://blog.csdn.net/weixin_34355881/article/details/90616273
代码如下
中文算法
package com.example.captcha;
import lombok.extern.slf4j.Slf4j;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.util.HashMap;
import java.util.Map;
import java.util.Random;
/**
* @author 李磊
* @datetime 2020/7/9 20:10
* @description
*/
@Slf4j
public class ChineseCaptcha {
// 宽度
private static final int IMAGE_WIDTH = 160;
// 高度
private static final int IMAGE_HEIGHT = 40;
// 字体大小
private static final int FONT_SIZE = 28;
// 干扰线数量
private static final int IMAGE_DISTURB_LINE_NUMBER = 15;
// 后缀
private static final String SUFFIX = "等于？";
// 汉字数字
private static final String SOURCE = "零一二三四五六七八九十乘除加减";
// 计算类型
private static final Map<String, Integer> calcType = new HashMap<>();
private static final Random RANDOM = new Random();
static {
// 对应SOURCE下标
calcType.put("*", 11);
calcType.put("/", 12);
calcType.put("+", 13);
calcType.put("-", 14);
}
// 计算公式
private String content;
// 计算结果
private int result;
/**
* 生成图像验证码
*/
public BufferedImage create() {
createMathChar();
BufferedImage image = new BufferedImage(IMAGE_WIDTH, IMAGE_HEIGHT, BufferedImage.TYPE_INT_RGB);
Graphics g = image.getGraphics();
// 字体颜色
g.setColor(Color.WHITE);
// 背景颜色
g.fillRect(0, 0, IMAGE_WIDTH, IMAGE_HEIGHT);
g.setColor(color());
// 图片边框
g.drawRect(0, 0, IMAGE_WIDTH - 1, IMAGE_HEIGHT - 1);
g.setColor(color());
for (int i = 0; i < IMAGE_DISTURB_LINE_NUMBER; i++) {
// 绘制干扰线
int x1 = RANDOM.nextInt(IMAGE_WIDTH);
int y1 = RANDOM.nextInt(IMAGE_HEIGHT);
int x2 = RANDOM.nextInt(13);
int y2 = RANDOM.nextInt(15);
g.drawLine(x1, y1, x1 + x2, y1 + y2);
}
StringBuilder builder = new StringBuilder();
for (int i = 0, j = content.length(); i < j; i++) {
int index;
if (i == 1) {
index = calcType.get(String.valueOf(content.charAt(i)));
} else {
index = Integer.parseInt(String.valueOf(content.charAt(i)));
}
String ch = String.valueOf(SOURCE.charAt(index));
builder.append(ch);
drawString((Graphics2D) g, ch, i);
}
drawString((Graphics2D) g, SUFFIX, 3);
content = builder.append(SUFFIX).toString();
g.dispose();
return image;
}
private void createMathChar() {
StringBuilder number = new StringBuilder();
// 10以内数字
int xx = RANDOM.nextInt(10);
int yy = RANDOM.nextInt(10);
// 0~3 对应加减乘除
int round = (int) Math.round(Math.random() * 3);
if (round == 0) {
this.result = yy + xx;
number.append(yy);
number.append("+");
number.append(xx);
} else if (round == 1) {
this.result = yy - xx;
number.append(yy);
number.append("-");
number.append(xx);
} else if (round == 2) {
this.result = yy * xx;
number.append(yy);
number.append("*");
number.append(xx);
} else {
// 0不可为被除数 yy对xx取余无余数
if (!(xx == 0) && yy % xx == 0) {
this.result = yy / xx;
number.append(yy);
number.append("/");
number.append(xx);
} else {
this.result = yy + xx;
number.append(yy);
number.append("+");
number.append(xx);
}
}
this.content = number.toString();
log.info("数字计算公式 {}", this.content);
}
private void drawString(Graphics2D g2d, String s, int i) {
g2d.setFont(new Font("黑体", Font.BOLD, FONT_SIZE));
int r = RANDOM.nextInt(255);
int g = RANDOM.nextInt(255);
int b = RANDOM.nextInt(255);
g2d.setColor(new Color(r, g, b));
int x = RANDOM.nextInt(3);
int y = RANDOM.nextInt(2);
g2d.translate(x, y);
int angle = new Random().nextInt() % 15;
g2d.rotate(angle * Math.PI / 180, 5 + i * 25, 20);
g2d.drawString(s, 5 + i * 25, 30);
g2d.rotate(-angle * Math.PI / 180, 5 + i * 25, 20);
}
// 获取随机颜色
private Color color() {
int r = RANDOM.nextInt(256);
int g = RANDOM.nextInt(256);
int b = RANDOM.nextInt(256);
return new Color(r, g, b);
}
public String content() {
return content;
}
public int result() {
return result;
}
}
数字算法
此代码使用了ttf字体 字体在此处 https://gitee.com/tothis/java-record/tree/master/src/main/resources/font
package com.example.captcha;
import lombok.SneakyThrows;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.util.Random;
/**
* @author 李磊
* @datetime 2020/7/9 20:16
* @description
*/
public class NumberCaptcha {
// 宽度
private static final int IMAGE_WIDTH = 160;
// 高度
private static final int IMAGE_HEIGHT = 40;
// 字体大小
private static final int FONT_SIZE = 28;
// 字体目录
private static final String FONT_PATH = "/font/";
// 字体列表
private static final String[] FONT_NAMES = {
"actionj.ttf", "epilog.ttf", "headache.ttf"
, "lexo.ttf", "prefix.ttf", "robot.ttf"
};
private static final Random RANDOM = new Random();
// 计算公式
private String content;
// 计算结果
private int result;
/**
* 生成随机验证码
*/
private void createMathChar() {
StringBuilder number = new StringBuilder();
int xx = RANDOM.nextInt(10);
int yy = RANDOM.nextInt(10);
// 0~3 对应加减乘除
int round = (int) Math.round(Math.random() * 3);
if (round == 0) {
this.result = yy + xx;
number.append(yy);
number.append("+");
number.append(xx);
} else if (round == 1) {
this.result = yy - xx;
number.append(yy);
number.append("-");
number.append(xx);
} else if (round == 2) {
this.result = yy * xx;
number.append(yy);
number.append("x");
number.append(xx);
} else {
// 0不可为被除数 yy对xx取余无余数
if (!(xx == 0) && yy % xx == 0) {
this.result = yy / xx;
number.append(yy);
number.append("/");
number.append(xx);
} else {
this.result = yy + xx;
number.append(yy);
number.append("+");
number.append(xx);
}
}
content = number.append("=?").toString();
}
// 获取随机颜色
private Color color() {
int r = RANDOM.nextInt(256);
int g = RANDOM.nextInt(256);
int b = RANDOM.nextInt(256);
return new Color(r, g, b);
}
/**
* 随机画干扰圆
*
* @param num 数量
* @param g Graphics2D
*/
private void drawOval(int num, Graphics2D g) {
for (int i = 0; i < num; i++) {
g.setColor(color());
int j = 5 + RANDOM.nextInt(10);
g.drawOval(RANDOM.nextInt(IMAGE_WIDTH - 25), RANDOM.nextInt(IMAGE_HEIGHT - 15), j, j);
}
}
@SneakyThrows
private Font font() {
int index = RANDOM.nextInt(FONT_NAMES.length);
Font font = Font.createFont(Font.TRUETYPE_FONT
, getClass().getResourceAsStream(FONT_PATH + FONT_NAMES[index]))
.deriveFont(Font.BOLD, FONT_SIZE);
return font;
}
/**
* 生成验证码图形
*/
public BufferedImage create() {
createMathChar();
char[] chars = content.toCharArray();
BufferedImage image = new BufferedImage(IMAGE_WIDTH, IMAGE_HEIGHT, BufferedImage.TYPE_INT_RGB);
Graphics2D g2d = (Graphics2D) image.getGraphics();
// 填充背景
g2d.setColor(Color.WHITE);
g2d.fillRect(0, 0, IMAGE_WIDTH, IMAGE_HEIGHT);
// 抗锯齿
g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
// 画干扰圆
drawOval(2, g2d);
// 画字符串
g2d.setFont(font());
FontMetrics fontMetrics = g2d.getFontMetrics();
// 每一个字符所占的宽度
int fx = IMAGE_WIDTH / chars.length;
// 字符左填充
int flp = 10;
for (int i = 0; i < chars.length; i++) {
String item = String.valueOf(chars[i]);
g2d.setColor(color());
// 文字的纵坐标
int fy = IMAGE_HEIGHT - ((IMAGE_HEIGHT - (int) fontMetrics
.getStringBounds(item, g2d).getHeight()) >> 1);
g2d.drawString(item, flp + i * fx + 3, fy - 3);
}
g2d.dispose();
return image;
}
public String content() {
return content;
}
public int result() {
return result;
}
}
测试类
package com.example.captcha;
import com.greenpineyu.fel.FelEngine;
import com.greenpineyu.fel.FelEngineImpl;
import lombok.SneakyThrows;
import javax.imageio.ImageIO;
import java.awt.image.BufferedImage;
import java.io.File;
/**
* @author 李磊
* @datetime 2020/7/9 20:10
* @description
*/
public class Main {
@SneakyThrows
public static void main(String[] args) {
// 图片类型
String IMAGE_TYPE = "png";
ChineseCaptcha chinese = new ChineseCaptcha();
NumberCaptcha number = new NumberCaptcha();
for (int i = 0; i < 10; i++) {
BufferedImage image1 = chinese.create();
// 输出文件
ImageIO.write(image1, IMAGE_TYPE, new File("D:/data/a" + i + ".png"));
System.out.println(chinese.content() + ' ' + chinese.result());
BufferedImage image2 = number.create();
// 输出文件
ImageIO.write(image2, IMAGE_TYPE, new File("D:/data/b" + i + ".png"));
System.out.println(number.content() + ' ' + number.result());
}
}
}
如需要多级运算如1+2-3*4/5 则需要使用表达式引擎计算 如下为使用fel计算表达式
// fel计算表达式
FelEngine fel = new FelEngineImpl();
System.out.println(3 * 2 + 1);
System.out.println(fel.eval("3*2+1"));
System.out.println(3 * (2 + 1));
System.out.println(fel.eval("3*(2+1)"));