Someone can fix or tell me what is wrong with this Java code? package projPak; i

Question

Someone can fix or tell me what is wrong with this Java code?

package projPak;
import java.util.*;
import javax.swing.JOptionPane;

public class Proj2 {
private int newArray[];
String input;
private int searchKey;

//More efficient binary search (sort array first)
   //Create three private data members newArray[] of ints and string input
   //and int searchKey
  
Proj2(){
   input = " ";
   searchKey = 0;
   newArray = new int [50];
   for(int i =0; i <newArray.length; i++) {
       newArray[i]= i*2;
   }
showArray();
}

   //constructor - create on that initializes input to null, searchKey to zero
   //and fills newArray with even numbers up to 100.
  
  
  

   //Starting class method
       public void startApp(){
           //take input from the user asking to search for what value
           input = JOptionPane.showInputDialog("Enter a search value: ");
           searchKey = Integer.parseInt(input);
          
           if(binarySearch()){
               JOptionPane.showMessageDialog(null, "The value "+searchKey+" was found!");
           }
           else{
               JOptionPane.showMessageDialog(null, "The value "+searchKey+" was not found!");
           }
          
       }
   //class method binarySearch
       public boolean binarySearch(){
           int low = 0;
           int high = newArray.length - 1;
           int middle;
           while(low <= high){
               middle = (low + high)/ 2;
               if(searchKey == newArray[middle]){
                   return true; //key found
               }
               else if(searchKey < newArray[middle]){
                   high = middle - 1;
               }
               else {
                   low = middle + 1;
               }
           }
           return false;
       }
      
       public void showArray(){
           for(int i = 0; i < newArray.length; i++){
               System.out.print(newArray[i] + " ");
           }
       }
       public static void main(String[] args) {
       //create and instantiate an object of type Proj2
      
       //use the object to start the application
   Proj2 obj = new Proj2();
     
   obj.startApp();
       }

}

}

Explanation / Answer

Proj2(){
   input = " ";
   searchKey = 0;
   newArray = new int [50];
   for(int i =0; i <newArray.length; i++) {
       newArray[i]= i*2;
   }
showArray();
}

newArray.length......since you are using constructor to fill data...but newArray is empty at this spot..then length is always zero

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