09번째 프로그램(성적처리) – 예외처리, 파일 읽기/쓰기

Posted on: 2019년 04월 03일 2019년 04월 03일
Categories: 강의자료, 자바

HighStudent.java : HighStudent 클래스를 사용하여 성적처리

package kr.ac.jj.java201812345;

import java.io.BufferedWriter;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Scanner;

public class HighStudent{
	String name = "No Name";
	int kor;
	int eng;
	int mat;
	int tot;
	double ave;
	String grade;

	public HighStudent() {

	}

	public HighStudent(int kor, int eng, int mat) {
		this.kor = kor;
		this.eng = eng;
		this.mat = mat;

		this.Calc();
	}

	public HighStudent(String name, int kor, int eng, int mat) {
		this(kor, eng, mat);
		this.name = name;
	}

	public void Calc() {
		this.tot = kor + eng + mat;
		this.ave = this.tot / 3.0;

		if(this.ave >= 90) {
			this.grade = "수";
		}
		else if(this.ave >= 80) {
			this.grade = "우";
		}
		else if(this.ave >= 70) {
			this.grade = "미";
		}
		else if(this.ave >= 60) {
			this.grade = "양";
		}
		else{
			this.grade = "가";
		}
	}

	public void Input() {
		Scanner scan = new Scanner(System.in);

		System.out.print("이름 : ");
		this.name = scan.nextLine();
		System.out.print("국어 : ");
		this.kor = scan.nextInt();
		System.out.print("영어 : ");
		this.eng = scan.nextInt();
		System.out.print("수학 : ");
		this.mat = scan.nextInt();

		this.Calc();
	}

	public void Print() {
		System.out.println(
				"이름 : " + this.name
				+ "\t국어 : " + this.kor
				+ "\t영어 : " + this.eng
				+ "\t수학 : " + this.mat
				+ "\t총점 : " + this.tot
				//+ "\t평균 : " + this.ave
				+ "\t평균 : " + String.format("%6.2f", this.ave)
				+ "\t등급 : " + this.grade
				);
	}

	public void PrintNew() {
		System.out.println(
				this.name
				+ "\t" + this.kor
				+ "\t" + this.eng
				+ "\t" + String.format("%3d", this.mat)
				+ "\t" + this.tot
				+ "\t" + String.format("%6.2f", this.ave)
				+ "\t" + this.grade
				);
	}

	public static void PrintHead() {
		System.out.println("이름\t국어\t영어\t수학\t총점\t평균\t등급");
	}

	public static void FilePrintHead() {
		PrintWriter out = null;

		try {
			out = new PrintWriter(new BufferedWriter(new FileWriter("D:\\out.txt", false)));
			out.println("이름\t국어\t영어\t수학\t총점\t평균\t등급");
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		finally {
			if(out != null) {
				out.close();
			}
		}
	}

	public void FilePrint() {
		PrintWriter out = null;

		try {
			out = new PrintWriter(new BufferedWriter(new FileWriter("D:\\out.txt", true)));
			out.println(
					this.name
					+ "\t" + this.kor
					+ "\t" + this.eng
					+ "\t" + this.mat
					+ "\t" + this.tot
					+ "\t" + String.format("%6.2f", this.ave)
					+ "\t" + this.grade
					);
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		finally {
			if(out != null) {
				out.close();
			}
		}
	}

}

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package kr.ac.jj.java201812345;

import java.io.BufferedWriter;

import java.io.FileWriter;

import java.io.IOException;

import java.io.PrintWriter;

import java.util.Scanner;

public class HighStudent{

String name = "No Name";

int kor;

int eng;

int mat;

int tot;

double ave;

String grade;

public HighStudent() {

}

public HighStudent(int kor, int eng, int mat) {

this.kor = kor;

this.eng = eng;

this.mat = mat;

this.Calc();

}

public HighStudent(String name, int kor, int eng, int mat) {

this(kor, eng, mat);

this.name = name;

}

public void Calc() {

this.tot = kor + eng + mat;

this.ave = this.tot / 3.0;

if(this.ave >= 90) {

this.grade = "수";

}

else if(this.ave >= 80) {

this.grade = "우";

}

else if(this.ave >= 70) {

this.grade = "미";

}

else if(this.ave >= 60) {

this.grade = "양";

}

else{

this.grade = "가";

}

public void Input() {

Scanner scan = new Scanner(System.in);

System.out.print("이름 : ");

this.name = scan.nextLine();

System.out.print("국어 : ");

this.kor = scan.nextInt();

System.out.print("영어 : ");

this.eng = scan.nextInt();

System.out.print("수학 : ");

this.mat = scan.nextInt();

this.Calc();

}

public void Print() {

System.out.println(

"이름 : " + this.name

+ "\t국어 : " + this.kor

+ "\t영어 : " + this.eng

+ "\t수학 : " + this.mat

+ "\t총점 : " + this.tot

//+ "\t평균 : " + this.ave

+ "\t평균 : " + String.format("%6.2f", this.ave)

+ "\t등급 : " + this.grade

);

}

public void PrintNew() {

System.out.println(

this.name

+ "\t" + this.kor

+ "\t" + this.eng

+ "\t" + String.format("%3d", this.mat)

+ "\t" + this.tot

+ "\t" + String.format("%6.2f", this.ave)

+ "\t" + this.grade

);

}

public static void PrintHead() {

System.out.println("이름\t국어\t영어\t수학\t총점\t평균\t등급");

}

public static void FilePrintHead() {

PrintWriter out = null;

try {

out = new PrintWriter(new BufferedWriter(new FileWriter("D:\\out.txt", false)));

out.println("이름\t국어\t영어\t수학\t총점\t평균\t등급");

} catch (IOException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

finally {

if(out != null) {

out.close();

}

public void FilePrint() {

PrintWriter out = null;

try {

out = new PrintWriter(new BufferedWriter(new FileWriter("D:\\out.txt", true)));

out.println(

this.name

+ "\t" + this.kor

+ "\t" + this.eng

+ "\t" + this.mat

+ "\t" + this.tot

+ "\t" + String.format("%6.2f", this.ave)

+ "\t" + this.grade

);

} catch (IOException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

finally {

if(out != null) {

out.close();

}

S009_Sungjuk.java : HighStudent 클래스를 사용하여 성적처리

package kr.ac.jj.java201812345;

import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.util.Scanner;

public class S009_Sungjuk {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		HighStudent[] st = new HighStudent[5];

		Scanner scan = null;
		try {
			scan = new Scanner(new BufferedReader(new FileReader("D:\\in.txt")));

			for(int i=0; i<st.length; i++) {
				String name = scan.next();
				int kor = scan.nextInt();
				int eng = scan.nextInt();
				int mat = scan.nextInt();
				st[i] = new HighStudent(name, kor, eng, mat);
			}

		} catch (FileNotFoundException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		finally {
			if(scan != null) {
				scan.close();
			}
		}

		HighStudent.FilePrintHead();
		for(int i=0; i<st.length; i++) {
			//st[i].Print();
			st[i].FilePrint();
		}
	}
}

package kr.ac.jj.java201812345;

import java.io.BufferedReader;

import java.io.FileNotFoundException;

import java.io.FileReader;

import java.util.Scanner;

public class S009_Sungjuk {

public static void main(String[] args) {

// TODO Auto-generated method stub

HighStudent[] st = new HighStudent[5];

Scanner scan = null;

try {

scan = new Scanner(new BufferedReader(new FileReader("D:\\in.txt")));

for(int i=0; i<st.length; i++) {

String name = scan.next();

int kor = scan.nextInt();

int eng = scan.nextInt();

int mat = scan.nextInt();

st[i] = new HighStudent(name, kor, eng, mat);

}

} catch (FileNotFoundException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

finally {

if(scan != null) {

scan.close();

}

HighStudent.FilePrintHead();

for(int i=0; i<st.length; i++) {

//st[i].Print();

st[i].FilePrint();

}

D:\in.txt 생성

홍길동 95 90 100 길동이 85 88 98 길동삼 100 89 99 길동사 99 98 97 길동오 87 100 84

1
2
3
4
5

홍길동 95 90 100
길동이 85 88 98
길동삼 100 89 99
길동사 99 98 97
길동오 87 100 84

실행 후 생성되는 D:\out.txt

이름	국어	영어	수학	총점	평균	등급
홍길동	95	90	100	285	 95.00	수
길동이	85	88	98	271	 90.33	수
길동삼	100	89	99	288	 96.00	수
길동사	99	98	97	294	 98.00	수
길동오	87	100	84	271	 90.33	수

이름 국어 영어 수학 총점 평균 등급

홍길동 95 90 100 285 95.00 수

길동이 85 88 98 271 90.33 수

길동삼 100 89 99 288 96.00 수

길동사 99 98 97 294 98.00 수

길동오 87 100 84 271 90.33 수

whan0623

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