My Python Code :

def import_file(file):
with open(file,"r") as f:
lines = f.readlines()
sline = []
for line in lines:
xline=line.split(" ")
sline.append(xline)
return sline

def set_file(idf,q,sline):
for i in sline:
if idf in i:
sline[sline.index(i)][1] = q + "\n"
return "Change succeeded"
sline.append([idf,q])
return "New code added"

def list_file(idf,sline):
for i in sline:
if idf in i:
return sline[sline.index(i)][1]
return "Not found"

def export_file(name,sline):
with open(name,'w') as f:
for lines in sline:
f.write(lines[0] + ' ' + lines[1])

loop = 1
while loop == 1:
choice=int(input("1:Import file\n 2:Set \n 3:List \n 4:Export file \n 5:Quit \n :"))
if choice == 1:
print("Importing file...")
use=import_file(input("Insert the path of the file:"))
elif choice == 2:
print("Setting file...")
print(set_file(input("Insert id:"),input("Insert quantity:"),use))
elif choice == 3:
print("Listing file...")
print(list_file(input("Insert id:"),use))
print(use)
elif choice == 4:
print("Exporting file...")
print(export_file(input("Name of the exported file:"),use))
elif choice == 5:
print("Goodbye")

loop = 0
My Java Code :

import java.util.*;
import java.io.*;

class ImportFile{
public static String[][] importFile(String fileName){
ArrayList<String> lines = new ArrayList<>();

try {
Scanner sc = new Scanner(new File(fileName));
while (sc.hasNextLine()) {
lines.add(sc.nextLine());
}
sc.close();
} catch (Exception e) {
e.printStackTrace();
}

String[][] slines = new String[lines.size()][];

int count = 0;
for(String line:lines){
String[] xline = line.split(" ");
slines[count] = xline;
count++;
}

return slines;
}
static void printDoubleArray(String[][] arr){
System.out.print("[");
for(int i = 0;i<arr.length;i++ ){
System.out.print("[");
for(int j = 0;j<arr[i].length;j++ ){
System.out.print(arr[i][j]);
if(j != arr[i].length-1) System.out.print(", ");
}
System.out.print("]");
if(i != arr.length-1) System.out.print(", ");
}
System.out.println("]");
}
public static void main(String[] args){
String [][] fileContent = importFile("text.txt");
printDoubleArray(fileContent);
}
}
how will I be able to achieve the desired result? It brings out only what is in text.txt while I want the following and the following legal execution :

import {file}: reads a text file where each line contains 2 integers separated by a space, the first number represents the product code and the second the new availability
set {id {{q}: changes the availability of a product with code {id} to {q}. If the product code does not exist, it is created
list {id}: prints the product availability with code {id}. If the password does not exist, print "not found"
export {file}: creates a text file corresponding to the import file
an indicative execution is the following:

import file1.txt
list 1234 # prints 0
set 1234 5
list 1234 # prints 5
list 1235 # prints 1
set 1235 0
list 1235 # prints 0
list 7897 # prints not found
set 7897 5
export file2.txt