avgofclass.java

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package file;

import java.io.File;
import java.io.RandomAccessFile;
import java.text.NumberFormat;

public class AvgOfClass {
	private float sumca=0.0f,summa=0.0f,sumea=0.0f,sumaa=0.0f,sum=0.0f;
    public void avgOfClass(int i){
    float sumc=0.0f,summ=0.0f,sume=0.0f,suma=0.0f;
    int number=0;
    String s;
    float chi,math,eng,avg;
    
	try{
    	RandomAccessFile raf,rafAvg;
        switch( i){
    	case 1:
    		File file1=new File(".","xsjb1.txt");
    		File f1=new File(".","xspj1.txt");
    	    raf=new RandomAccessFile(file1,"r");
    	    rafAvg=new RandomAccessFile(f1,"rw");
    		break;
    	case 2:
    		File file2=new File(".","xsjb2.txt");
    		File f2=new File(".","xspj2.txt");
    		raf=new RandomAccessFile(file2,"r");
    		rafAvg=new RandomAccessFile(f2,"rw");
    		break;
    	case 3:
    		File file3=new File(".","xsjb3.txt");
    		File f3=new File(".","xspj3.txt");
    		raf=new RandomAccessFile(file3,"r");
    		rafAvg=new RandomAccessFile(f3,"rw");
    		break;
    	default:
    		File file4=new File(".","xsjb4.txt");
    	    File f4=new File(".","xspj4.txt");
    		raf=new RandomAccessFile(file4,"r");
    		rafAvg=new RandomAccessFile(f4,"rw");
    		break;
        }
        while(raf.getFilePointer() !=raf.length() ){
            number++;       
        	s=raf.readLine() ;
        	chi=Float.parseFloat( AnalyseString.getChinese ( s));
        	math=Float.parseFloat( AnalyseString.getEnglish( s));
        	eng=Float.parseFloat( AnalyseString.getMath ( s));
        	avg=Float.parseFloat( AnalyseString.getAvg(  s));
        	sumc=sumc+chi;
        	summ=summ+math;
        	sume=sume+eng;
        	suma=suma+avg;
        }
        
        sumca=sumc/number;
        summa=summ/number;
        sumea=sume/number;
        sumaa=suma/number;
    	sum=sumc+summ+sume;
    }
	catch(Exception e){
		System.out.println(e);
	}
}
    public float getAvgChinese(){
    	return format(sumca);
    }
    public float getAvgMath(){
    	return format(summa);
    }
    public float getAvgEnglish(){
    	return format(sumea);
    }
    public float getAvgSum(){
    	return format(sumaa);
    }
    public float getSum(){
    	return format(sum);
    }
    public float format(float f){
		NumberFormat nf=NumberFormat.getInstance() ;
		nf.setMaximumIntegerDigits( 3);
		nf.setMaximumFractionDigits( 2);
		return Float.parseFloat( nf.format(f));
    }
}