Java：将String数组项解析为，int，double或string

Question

import java.io.File;
import java.io.FileNotFoundException;
import java.util.Arrays;
import java.util.Scanner;


public class DataStructure {
 public static void main(String[] aArgs) {
     String [] fileContents=new String[6];
     File testFile = new File ("testFile.txt");

     try{
         Scanner testScanner = new Scanner(testFile);
         int i=0;
         while (i < fileContents.length){
             fileContents[i]=testScanner.nextLine();
         i++;
         }
         testScanner.close();
     }
 catch (FileNotFoundException e) {
      e.printStackTrace();
 }
     finally{
         System.out.println(Arrays.toString(fileContents)); 

     }
     }

 }

Above is what I have already for my program. What I want to do is convert the items from the string array created in the try section and parse that further into specific useable variables, int, double ect. Should I instead just parse the string when its created and scrap the array? I am not sure how to proceed in parsing the string array. Any help would be great...I am really new to java...

Answer 1

import java.io.File;
import java.io.FileNotFoundException;
import java.util.Arrays;
import java.util.Scanner;
import java.util.ArrayList;
import java.util.List;

public class DataStructure {
 public static void main(String[] aArgs) {
     String [] fileContents=new String[6];
     ArrayList<Integer> intList = new ArrayList<>();
     ArrayList<Double> doubList = new ArrayList<>();

     File testFile = new File ("testFile.txt");

     try{
         Scanner testScanner = new Scanner(testFile);
         int i=0;
         while (i < fileContents.length){
             fileContents[i]=testScanner.nextLine();
             i++;
         }
         testScanner.close();
     }
 catch (FileNotFoundException e) {
      e.printStackTrace();
 }
     finally{
         System.out.println(Arrays.toString(fileContents)); 
         for( int i = 0; i < fileContents.length; i++ ){
            if(fileContents[i].contains(".")){
                doubList.add(Double.parseDouble(fileContents[i]));
            }else{
                intList.add(Integer.parseInt(fileContents[i]));
            }
         }
         for(int i = 0; i < intList.size(); i++ ){
            System.out.println(intList.get(i));
         }
         System.out.println(" ");
         for(int i = 0; i < doubList.size(); i++ ){
            System.out.println(doubList.get(i));
         }
     }
     }

 }

since doubles and floats and practically the same thing just one of them being able to hold a larger data value, i took all floats/doubles in as a double and the integers as a int. I tested each string to see if it contained a "." period character and if it did, i added it to my doubles arraylist and if it didn't, i added it to my integers arrayList.