それ以外の場合は他のJavaで実行する場合

Question

私は理解できないように見えるこの問題に苦しんでいる、私は完全に新しいJavaと私は助けが必要です..私はあなたが合格したかどうかを判断する簡単なプログラムを作っている対象かどうかの点の成績を経由して、それはそうです、それはここでしか... ELSE文を決定するコードです...それは本当に...事前のおかげで

String studID=" ",course=" ", name=" ", dept=" ", subj=" "; 
    double exam1=0, exam2=0, exam3=0, exam4=0; 
    double avg, pgrade; 
    String msg=" "; 

studID =JOptionPane.showInputDialog("Please fill-out the following fields:" 
     + "\nStudent ID: "); 
name = JOptionPane.showInputDialog("Name: "); 
dept = JOptionPane.showInputDialog("Department: "); 
course = JOptionPane.showInputDialog("Course: "); 
subj = JOptionPane.showInputDialog("Subject: "); 
exam1 = Double.parseDouble(JOptionPane.showInputDialog("First Examination: ")); 
exam2 = Double.parseDouble(JOptionPane.showInputDialog("Second Examination: ")); 
exam3 = Double.parseDouble(JOptionPane.showInputDialog("Third Examination: ")); 
exam4 = Double.parseDouble(JOptionPane.showInputDialog("Final Examination: ")); 
avg = (exam1 + exam2 + exam3 + exam4)/4; 
pgrade =(100 - avg + 10)/10; 

if (avg==100) 
{ 
    msg = "passed - Excellent!"; 
}else if (avg>100 && avg<89) 
{ 
    msg = "Passed - Very Good!"; 
}else if (avg>90 && avg<84) 
{ 
    msg = "Passed - Average"; 
}else if (avg>85 && avg<79) 
{ 
    msg = "Passed - Good"; 
}else if (avg>80 && avg<74) 
{ 
    msg = "Passed - Satisfactory"; 
}else if (avg>75 && avg<49) 
{ 
    msg = "Failed"; 
}else if (avg>50 && avg<0.00) 
{ 
    msg = "Dropped"; 
}else if (avg==0.00 && avg<0.00) 
{ 
    msg = "No such Grade"; 
}else 
{ 
    msg = "Out of Range or Invalid."; 
} 


JOptionPane.showMessageDialog(null, new JTextArea (
     "|======Student Details=======|" 
    + "\n|StudentID:\t" + studID +"\t |" 
    + "\n|Name:\t" + name + "\t |" 
    + "\n|Department:\t" +dept+ "\t |" 
    + "\n|Course:\t"+course+"\t |" 
    + "\n|Subject:\t"+subj + "\t |" 
    + "\n|=======Grade Details======= |" 
    + "\n|First  Second  Third  Fourth |" 
    + "\n|"+exam1+"  "+exam2+"  "+exam3+"  "+exam4+"\t  |" 
    + "\n|Average:\t" +avg + "\t|" 
    + "\n|Point Grade\t:" +pgrade+"\t|" 
    + "\n|Remarks:"+msg+"\t|" 
    + "\n|=============================|")); 





} 

}

Answer 1

条件が間違っているたくさん私を助けますあなたが設定しなければならない範囲に変数を含めるため、

else if(avg>89 && avg<100) 

Answer 2

あなたの比較はまず間違っていましたので、私が訂正した線に沿って試してみてください。

String studID=" ",course=" ", name=" ", dept=" ", subj=" "; 
    double exam1=0, exam2=0, exam3=0, exam4=0; 
    double avg, pgrade; 
    String msg=" "; 

studID =JOptionPane.showInputDialog("Please fill-out the following fields:" 
     + "\nStudent ID: "); 
name = JOptionPane.showInputDialog("Name: "); 
dept = JOptionPane.showInputDialog("Department: "); 
course = JOptionPane.showInputDialog("Course: "); 
subj = JOptionPane.showInputDialog("Subject: "); 
exam1 = Double.parseDouble(JOptionPane.showInputDialog("First Examination: ")); 
exam2 = Double.parseDouble(JOptionPane.showInputDialog("Second Examination: ")); 
exam3 = Double.parseDouble(JOptionPane.showInputDialog("Third Examination: ")); 
exam4 = Double.parseDouble(JOptionPane.showInputDialog("Final Examination: ")); 
avg = (exam1 + exam2 + exam3 + exam4)/4; 
pgrade =(100 - avg + 10)/10; 

if (avg==100) 
{ 
    msg = "passed - Excellent!"; 
}else if (avg<100 && avg>89) 
{ 
    msg = "Passed - Very Good!"; 
}else if (avg<90 && avg>84) 
{ 
    msg = "Passed - Average"; 
}else if (avg<85 && avg>79) 
{ 
    msg = "Passed - Good"; 
}else if (avg<80 && avg>74) 
{ 
    msg = "Passed - Satisfactory"; 
}else if (avg<75 && avg>49) 
{ 
    msg = "Failed"; 
}else if (avg<50 && avg>0.00) 
{ 
    msg = "Dropped"; 
}else if (avg==0.00)//no one gets below zero in a fair system 
{ 
    msg = "No such Grade"; 
}else 
{ 
    msg = "Out of Range or Invalid."; 
} 


JOptionPane.showMessageDialog(null, new JTextArea (
     "|======Student Details=======|" 
    + "\n|StudentID:\t" + studID +"\t |" 
    + "\n|Name:\t" + name + "\t |" 
    + "\n|Department:\t" +dept+ "\t |" 
    + "\n|Course:\t"+course+"\t |" 
    + "\n|Subject:\t"+subj + "\t |" 
    + "\n|=======Grade Details======= |" 
    + "\n|First  Second  Third  Fourth |" 
    + "\n|"+exam1+"  "+exam2+"  "+exam3+"  "+exam4+"\t  |" 
    + "\n|Average:\t" +avg + "\t|" 
    + "\n|Point Grade\t:" +pgrade+"\t|" 
    + "\n|Remarks:"+msg+"\t|" 
    + "\n|=============================|")); 





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