获取验证码逻辑，无需加锁，不涉及线程安全问题，提高效率 (#755)

eladmin-system/src/main/java/me/zhengjie/modules/security/config/bean/LoginProperties.java

@@ -68,33 +68,31 @@ public class LoginProperties {
      */
     private Captcha switchCaptcha(LoginCode loginCode) {
         Captcha captcha;
-        synchronized (this) {
-            switch (loginCode.getCodeType()) {
-                case ARITHMETIC:
-                    // 算术类型 https://gitee.com/whvse/EasyCaptcha
-                    captcha = new FixedArithmeticCaptcha(loginCode.getWidth(), loginCode.getHeight());
-                    // 几位数运算，默认是两位
-                    captcha.setLen(loginCode.getLength());
-                    break;
-                case CHINESE:
-                    captcha = new ChineseCaptcha(loginCode.getWidth(), loginCode.getHeight());
-                    captcha.setLen(loginCode.getLength());
-                    break;
-                case CHINESE_GIF:
-                    captcha = new ChineseGifCaptcha(loginCode.getWidth(), loginCode.getHeight());
-                    captcha.setLen(loginCode.getLength());
-                    break;
-                case GIF:
-                    captcha = new GifCaptcha(loginCode.getWidth(), loginCode.getHeight());
-                    captcha.setLen(loginCode.getLength());
-                    break;
-                case SPEC:
-                    captcha = new SpecCaptcha(loginCode.getWidth(), loginCode.getHeight());
-                    captcha.setLen(loginCode.getLength());
-                    break;
-                default:
-                    throw new BadConfigurationException("验证码配置信息错误！正确配置查看 LoginCodeEnum ");
-            }
+        switch (loginCode.getCodeType()) {
+            case ARITHMETIC:
+                // 算术类型 https://gitee.com/whvse/EasyCaptcha
+                captcha = new FixedArithmeticCaptcha(loginCode.getWidth(), loginCode.getHeight());
+                // 几位数运算，默认是两位
+                captcha.setLen(loginCode.getLength());
+                break;
+            case CHINESE:
+                captcha = new ChineseCaptcha(loginCode.getWidth(), loginCode.getHeight());
+                captcha.setLen(loginCode.getLength());
+                break;
+            case CHINESE_GIF:
+                captcha = new ChineseGifCaptcha(loginCode.getWidth(), loginCode.getHeight());
+                captcha.setLen(loginCode.getLength());
+                break;
+            case GIF:
+                captcha = new GifCaptcha(loginCode.getWidth(), loginCode.getHeight());
+                captcha.setLen(loginCode.getLength());
+                break;
+            case SPEC:
+                captcha = new SpecCaptcha(loginCode.getWidth(), loginCode.getHeight());
+                captcha.setLen(loginCode.getLength());
+                break;
+            default:
+                throw new BadConfigurationException("验证码配置信息错误！正确配置查看 LoginCodeEnum ");
         }
         if(StringUtils.isNotBlank(loginCode.getFontName())){
             captcha.setFont(new Font(loginCode.getFontName(), Font.PLAIN, loginCode.getFontSize()));