我需要创建一个 add 方法来添加用户输入的英尺和英寸。用户可以输入任何以英尺或英寸为单位的整数，然后将其取回，但我需要添加这些值。我不完全确定我该如何处理。任何帮助都会很棒！
以下是我的代码：
import java.util.Scanner;
public class MixWithUnit_JM {
Fraction_JM a;
int first;
int second;
public String displayMixWithUnit_JM() {
String str="";
if (first == 0) str= first%second+"/"+second+"in";
else if (first%second == 0) str= ""+first/second+"ft";
else if (first < second) str=first+"/"+second+"in";
else str= first/second+"ft" +" "+ first%second+"/"+second+"in";
return str;
}//display
public MixWithUnit_JM(String str) {
int pos = str.indexOf("ft");
int pos2 = str.indexOf("in");
String a1 = "";
String a2 ="";
String b1 = "";
String b2 ="";
String b3 ="";
if(pos == -1){
a2 = str.substring(0,pos2 +2).trim();
b2 = str.substring(0,pos2);
b3 = b2;
}
else if(pos2 == -1){
a1 = str.substring(0,pos +2);
b1 = str.substring(0, pos);
b3 = b1;
}
else{
a1 = str.substring(0,pos +2);
b1 = str.substring(0, pos);
a2 = str.substring(pos +2).trim();
b2 = str.substring(pos+2, str.length()-2);
b3 = b1 + b2;
}
int[] iA= parse (b3);
int top=iA[0]*iA[2]+iA[1];
int bot= iA[2];
a = new Fraction_JM (top,bot);
int gcd = a.gcd(top,bot);
first=top/gcd;
second =bot/gcd;
}//Mix
public static String get (){
Scanner scan = new Scanner (System.in);
String userInput = scan.nextLine();
userInput =userInput.trim();
return (userInput);
} //get
public static int[] parse (String userInput){
int iNum = 0;
int iTop = 0;
int iBot = 1;
userInput = userInput.trim();
int pos = userInput.indexOf(" ");
int pos2 = userInput.indexOf("/");
if (pos == -1 && pos2 != -1){
pos= userInput.indexOf("/");
String sTop=userInput.substring(0,pos);
iTop = Integer.parseInt(sTop);//second integer
String sBot=userInput.substring(pos+1);
iBot = Integer.parseInt(sBot);//third integer
//case 2
}
else if (pos == -1 && pos2== -1) {
iNum = Integer.parseInt(userInput);//first integer
//case 1
}
else{
String sNum=userInput.substring(0,pos);
iNum = Integer.parseInt(sNum);//first integer
String sNum2=userInput.substring(pos+1);
pos= sNum2.indexOf("/");
String sTop=sNum2.substring(0,pos);
iTop = Integer.parseInt(sTop);//second integer
String sBot=sNum2.substring(pos+1);
iBot = Integer.parseInt(sBot);//third integer
}
int[] sA = {iNum,iTop,iBot};
return (sA);
} //parse
public static void main(String[] args) {
System.out.print("Please enter a mixed-format number :");
String userInput = MixWithUnit_JM.get();
System.out.println("Input is: "+userInput);
MixWithUnit_JM s = new MixWithUnit_JM(userInput);
s.displayMixWithUnit_JM();
System.out.print("Please enter a mixed-format number :");
userInput = MixWithUnit_JM.get();
System.out.println("Input is: "+userInput);
MixWithUnit_JM s2 = new MixWithUnit_JM(userInput);
s2.displayMixWithUnit_JM();
}//main
}//class
程序运行，我只需要一个 add 方法。