java繪圖相關類

驗證碼工具類

package dt2008.util;

import javax.imageio.ImageIO;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import java.awt.*;

import java.awt.image.BufferedImage;

import java.io.IOException;

import java.util.Random;

/**

* 驗證碼工具類

*/

public class RandomValidateCodeUtil {

//定義隨機類

private Random random = new Random();

public void code(HttpServletRequest request, HttpServletResponse response){

//1.創建緩存圖片類

//構造方法：new BufferedImage(int width,int height,int model)

BufferedImage image = new BufferedImage(150,50,BufferedImage.TYPE_INT_RGB);

//2.獲取畫筆

Graphics g = image.getGraphics();

//3.設置畫筆顏色

g.setColor(Color.white);//白色

//4.填充矩形

//g.fillRect(x,y,width,height); x,y 起點的坐標，width矩形寬度，height矩形的高度

g.fillRect(0,0,150,50);

//5.畫矩形邊框

//設置畫筆顏色(邊框的顏色)

g.setColor(Color.blue);//藍色

//畫邊框的語法：g.drawRect(x,y,width,height); x,y 起點的坐標，width邊框寬度，height邊框的高度

g.drawRect(1,1,147,47);

//6.畫4條干擾線

//畫直線語法：g.drawLine(x1,y1,x2,y2); x1,y1 線的起點坐標，x2,y2先的終點坐標

for (int i = 0; i < 4; i++) {

//設置畫筆為隨機顏色

g.setColor(getRandomColor());

//隨機獲取2個點

int x1 = random.nextInt(147)+1;

int y1 = random.nextInt(47)+1;

int x2 = random.nextInt(147)+1;

int y2 = random.nextInt(47)+1;

//畫直線

g.drawLine(x1,y1,x2,y2);

}

//7.畫驗證碼字符串

String checkCodeScope = "qwertyupasdfghjkzxcvbnm";

//定義接收拼接隨機獲取到的驗證碼字符變量

StringBuilder checkCodeBuilder = new StringBuilder();

//循環隨機獲取4個驗證碼字符

for (int i = 0; i < 4; i++) {

//獲取隨機位置

int index = random.nextInt(checkCodeScope.length());

//根據位置獲取字符

char c = checkCodeScope.charAt(index);

//checkCodeBuilder拼接獲取的隨機字符

checkCodeBuilder.append(c);

//設置畫筆的字體

//字符構造方法：new Font(字體，樣式，大小)

g.setFont(new Font("微軟雅黑",Font.BOLD,20));

//將每個字符畫到圖片上

//語法：g.drawString(字符串,x,y);

g.drawString(c+"",30+i*30,30);

}

request.getSession().setAttribute("SESSION_CHECKCODE", checkCodeBuilder.toString());

//8.將驗證碼圖片輸出給瀏覽器

//輸出緩存圖片的語法：ImageIO.write(緩存圖片,圖片的格式,輸出給瀏覽器的字節流);

try {

ImageIO.write(image,"png",response.getOutputStream());

} catch (IOException e) {

e.printStackTrace();

}

}

//獲取隨機的顏色

private Color getRandomColor(){

int r = random.nextInt(256);

int g = random.nextInt(256);

int b = random.nextInt(256);

//構造方法語法：new Color(int r,int g,int b) //由紅、綠、藍組成， 每個顏色值范圍0~255

return new Color(r,g,b);

}

}

Controller(生成驗證碼)

package yingshi.web;

import org.slf4j.Logger;

import org.slf4j.LoggerFactory;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.web.bind.annotation.RequestMapping;

import org.springframework.web.bind.annotation.RequestMethod;

import org.springframework.web.bind.annotation.RequestParam;

import org.springframework.web.bind.annotation.RestController;

import yingshi.util.RandomValidateCodeUtil;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import javax.servlet.http.HttpSession;

import java.io.IOException;

/**

* 登錄以及驗證碼

*/

@RestController

@RequestMapping("login/admin")

public class LoginController {

/**

* 生成驗證碼

*/

@RequestMapping("getVerify")

public void getVerify(HttpServletRequest request, HttpServletResponse response) {

RandomValidateCodeUtil randomValidateCodeUtil = new RandomValidateCodeUtil();

randomValidateCodeUtil.code(request, response);

}

}

這時，可以訪問驗證碼了，可以在前端那寫個js點擊切換驗證碼

接下來就是校驗驗證碼(注意：是分大小寫的)

package yingshi.web;

import org.slf4j.Logger;

import org.slf4j.LoggerFactory;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.web.bind.annotation.RequestMapping;

import org.springframework.web.bind.annotation.RequestMethod;

import org.springframework.web.bind.annotation.RequestParam;

import org.springframework.web.bind.annotation.RestController;

import yingshi.util.RandomValidateCodeUtil;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import javax.servlet.http.HttpSession;

import java.io.IOException;

/**

* 登錄以及驗證碼

*/

@RestController

@RequestMapping("login/admin")

public class LoginController {

/**

* 校驗后臺登錄

*/

@RequestMapping("checkVerify")

public String checkVerify(String username, String password, String verifyInput, HttpServletRequest request, HttpServletResponse response) {

//驗證碼校驗

//獲取session中的驗證碼

String sessionCheckCode = (String) request.getSession().getAttribute("SESSION_CHECKCODE");

//判斷驗證碼是否正確

if(!verifyInput.equals(sessionCheckCode)){

return "錯誤";

}else{

return "正確";

}

}

}

希望這篇文章對您有幫助！

總結

以上是生活随笔為你收集整理的java 生成校验验证码_java 验证码生成与校验的全部內容，希望文章能夠幫你解決所遇到的問題。

如果覺得生活随笔網站內容還不錯，歡迎將生活随笔推薦給好友。