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What is the reason for the null pointer exception in getEmployeeDetails(String[] details).? What is the best way to resolve this? getEmployeeDetails method converts the employee details from the array of Strings to the array of Employee objects. I need to return the array of string have details of employees having salary more than the minimum salary.

What I have tried:

Java
import java.util.stream.Stream;
import java.util.Arrays;
import java.util.List;
import java.util.stream.Stream;
import java.util.stream.Collectors;
import java.util.ArrayList;
import java.util.Collections;
public class EmployeeUtility {

//@NotNull
public Employee[] getEmployeeDetails(String[] details) {

	//Fill your code here
	Employee[] emp_arr=new Employee[details.length];
	for(int i=0;i<details.length;i++)
{
    string[] split_details="details[i].split(";");
    system.out.println(split_details[0]+" "+split_details[1]+" "+split_details[2]);
    emp_arr[i].setempid( split_details[0]);
    emp_arr[i].setempname( split_details[1]);
    emp_arr[i].setsalary( double.valueof(split_details[2]));
 
 }
 return emp_arr;



 }

 public stream<employee=""> getStreamOfEmployee(Employee[] empDetails) {

		//Fill your code here
		
		Stream emp_stream=Arrays.stream(empDetails);
        return emp_stream;


	}

	public String[] shortlistedEmployee(Stream<employee> empStream,double minSalary) {

		//Fill your code here
		List<string> result=new ArrayList<string>();
		List<employee> empList=empStream.collect(Collectors.toList());
		int i=0;
		for(Employee obj:empList)
		{
		    String str="";
		    if(obj.getSalary()>=minSalary)
		    {
		        str=obj.getEmpId()+";"+obj.getEmpName()+";"+obj.getSalary();
		        result.add(str);
		    }
		}
		Collections.sort(result);
		String[] result_array=result.toArray(new String[result.size()]);
		//Collections.sort(result_array);
		return result_array;
	}

}



public class Employee {
	private String empId;
	private String empName;
	private double salary;

	public String getEmpId() {
		return empId;
	}
	public void setEmpId(String empId) {
		this.empId = empId;
	}
	public String getEmpName() {
		return empName;
	}
	public void setEmpName(String empName) {
		this.empName = empName;
	}
	public double getSalary() {
		return salary;
	}
	public void setSalary(double salary) {
		this.salary = salary;
	}
}



<pre>import java.util.Scanner;
//DO NOT EDIT OR DELETE
public class Main {

	public static void main(String[] args) {
		Scanner sc=new Scanner(System.in);
		EmployeeUtility utilObj=new EmployeeUtility();
		System.out.println("Enter the number of Employees");
		int n=sc.nextInt();
		sc.nextLine();
		if(n>0) {
			System.out.println("Enter the details of Employees");
			String [] details=new String[n];
			for(int i=0;i<n;i++) {
 details[i]="sc.nextLine();
}
 system.out.println("enter the minimum eligible salary");
 double minsalary="sc.nextDouble();

string[] result="utilObj.shortlistedEmployee(utilObj.getStreamOfEmployee(utilObj.getEmployeeDetails(details)),minSalary);
if(result.length="">0)	{
				System.out.println("Shortlisted Employees are");
				for(String s:result) {
					System.out.println(s);
				}
			}
			else {
				System.out.println("No Employee is having the required salary");
			}
		}
		else
		{
			System.out.println("Invalid Input");
		}
	}
}
Posted
Updated 15-Apr-21 4:43am
v2

1 solution

This is one of the most common problems we get asked, and it's also the one we are least equipped to answer, but you are most equipped to answer yourself.

Let me just explain what the error means: You have tried to use a variable, property, or a method return value but it contains null - which means that there is no instance of a class in the variable.
It's a bit like a pocket: you have a pocket in your shirt, which you use to hold a pen. If you reach into the pocket and find there isn't a pen there, you can't sign your name on a piece of paper - and you will get very funny looks if you try! The empty pocket is giving you a null value (no pen here!) so you can't do anything that you would normally do once you retrieved your pen. Why is it empty? That's the question - it may be that you forgot to pick up your pen when you left the house this morning, or possibly you left the pen in the pocket of yesterday's shirt when you took it off last night.

We can't tell, because we weren't there, and even more importantly, we can't even see your shirt, much less what is in the pocket!

Back to computers, and you have done the same thing, somehow - and we can't see your code, much less run it and find out what contains null when it shouldn't.
But you can - and the debugger will help you here. Run your program in the debugger and when it fails, the debugger will show you the line it found the problem on. You can then start looking at the various parts of it to see what value is null and start looking back through your code to find out why. So put a breakpoint at the beginning of the method containing the error line, and run your program from the start again. This time, the debugger will stop before the error, and let you examine what is going on by stepping through the code looking at your values.

But we can't do that - we don't have your code, we don't know how to use it if we did have it, we don't have your data. So try it - and see how much information you can find out!
   

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