优化及清理代码

src/main/java/cn/com/qmth/examcloud/support/cache/bean/ExamStudentCacheBean.java

@@ -56,7 +56,7 @@ public class ExamStudentCacheBean extends RandomCacheBean {
 	/**
 	 * 年级
 	 */
-	private String Grade;
+	private String grade;
 
 	public Long getExamStudentId() {
 		return examStudentId;
@@ -123,10 +123,10 @@ public class ExamStudentCacheBean extends RandomCacheBean {
 	}
 
 	public String getGrade() {
-		return Grade;
+		return grade;
 	}
 
 	public void setGrade(String grade) {
-		Grade = grade;
+		this.grade = grade;
 	}
 }