两道java程序题 新手请教要怎么写？

import java.math.BigDecimal;

public class JavaCourse {

private String sName; //学生姓名
private String sId; //学号
private int testGrade; //测试成绩
private int regularGrade; //平时成绩
private int endOfTermGrade;//期末成绩
private int totalGrade; //总成绩
public final double TR= 0.3;
public final double RR= 0.3;
public final double ER= 0.4;

public JavaCourse() {
}

public JavaCourse(String sName, String sId, int testGrade, int regularGrade, int endOfTermGrade) {
this.sName = sName;
this.sId = sId;
this.testGrade = testGrade;
this.regularGrade = regularGrade;
this.endOfTermGrade = endOfTermGrade;
}

public String getsName() {
return sName;
}

public void setsName(String sName) {
this.sName = sName;
}

public String getsId() {
return sId;
}

public void setsId(String sId) {
this.sId = sId;
}

public int getTestGrade() {
return testGrade;
}

public void setTestGrade(int testGrade) {
this.testGrade = testGrade;
}

public int getRegularGrade() {
return regularGrade;
}

public void setRegularGrade(int regularGrade) {
this.regularGrade = regularGrade;
}

public int getEndOfTermGrade() {
return endOfTermGrade;
}

public void setEndOfTermGrade(int endOfTermGrade) {
this.endOfTermGrade = endOfTermGrade;
}

public int getTotalGrade() {
return totalGrade;
}

@Override
public String toString() {
return "JavaCourse{" +
"sName='" + sName + '\'' +
", sId='" + sId + '\'' +
", testGrade=" + testGrade +
", regularGrade=" + regularGrade +
", endOfTermGrade=" + endOfTermGrade +
'}';
}

public void showTotalGrad() {
//double四舍五入（0.5->1）转int类型
totalGrade = Integer.parseInt(new BigDecimal((testGrade * TR + regularGrade * RR + endOfTermGrade * ER)).setScale(0, BigDecimal.ROUND_HALF_UP).toString());
System.out.println("课程的总成绩：" + totalGrade);
}
}

public class DemoTest02 {

public static void main(String[] args) {
JavaCourse student1 = new JavaCourse();
student1.setsName("小张");
student1.setsId("10086");
student1.setTestGrade(85);
student1.setRegularGrade(90);
student1.setEndOfTermGrade(86);
System.out.println(student1.toString());
student1.showTotalGrad();

JavaCourse student2 = new JavaCourse("老王","10010",60,80,45);
System.out.println(student2.toString());
student2.showTotalGrad();
}
}