EasyCaptcha/src/main/java/com/wf/captcha/ChineseCaptcha.java

109 lines
3.2 KiB
Java

package com.wf.captcha;
import javax.imageio.ImageIO;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.io.OutputStream;
public class ChineseCaptcha extends ChineseCaptchaAbstract {
public ChineseCaptcha() {
super();
}
public ChineseCaptcha(int width, int height) {
this();
setWidth(width);
setHeight(height);
}
public ChineseCaptcha(int width, int height, int len) {
this(width, height);
setLen(len);
}
public ChineseCaptcha(int width, int height, int len, Font font) {
this(width, height, len);
setFont(font);
}
/**
* 生成验证码
*
* @param out 输出流
* @return 是否成功
*/
@Override
public boolean out(OutputStream out) {
checkAlpha();
return graphicsImage(textChar(), out);
}
/**
* 生成验证码图形
*
* @param strs 验证码
* @param out 输出流
* @return boolean
*/
private boolean graphicsImage(char[] strs, OutputStream out) {
boolean ok;
try {
BufferedImage bi = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
Graphics2D g = (Graphics2D) bi.getGraphics();
AlphaComposite ac3;
int len = strs.length;
g.setColor(Color.WHITE);
g.fillRect(0, 0, width, height);
// 抗锯齿
g.setColor(color());
g.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
int hp = (height - font.getSize()) >> 1;
int h = height - hp;
int w = width / strs.length;
int sp = (w - font.getSize()) / 2;
// 画字符串
for (int i = 0; i < len; i++) {
// 计算坐标
int x = i * w + sp + num(-5, 5);
int y = h + num(-5, 5);
if (x < 5) {
x = 5;
}
if (x + font.getSize() > width) {
x = width - font.getSize();
}
if (y > height) {
y = height;
}
if (y - font.getSize() < 0) {
y = font.getSize();
}
g.setFont(font.deriveFont(num(2) == 0 ? Font.PLAIN : Font.ITALIC));
g.drawString(String.valueOf(strs[i]), x, y);
}
// 随机画干扰线
g.setStroke(new BasicStroke(1.25f, BasicStroke.CAP_BUTT, BasicStroke.JOIN_BEVEL));
ac3 = AlphaComposite.getInstance(AlphaComposite.SRC_OVER, 0.7f); // 指定透明度
g.setComposite(ac3);
drawLine(2, g.getColor(), g);
// 画干扰圆圈
drawOval(5, g.getColor(), g);
ImageIO.write(bi, "png", out);
out.flush();
ok = true;
} catch (IOException e) {
ok = false;
e.printStackTrace();
} finally {
try {
out.close();
} catch (IOException e) {
e.printStackTrace();
}
}
return ok;
}
}