package com.javabrahman.java8.collector;

import java.util.Arrays;
import java.util.IntSummaryStatistics;
import java.util.List;
import java.util.LongSummaryStatistics;
import java.util.DoubleSummaryStatistics;
import java.util.stream.Collectors;
import com.javabrahman.java8.Employee;
public class SummarizingCollectors {
  static List<Employee> employeeList
      = Arrays.asList(new Employee("Tom Jones", 45, 15000.00,190),
      new Employee("Tom Jones", 45, 7000.00,220),
      new Employee("Ethan Hardy", 65, 8000.00,1008),
      new Employee("Nancy Smith", 22, 10000.00,5),
      new Employee("Deborah Sprightly", 29, 9000.00,45));

  public static void main(String[] args) {
    //Using Collectors.summarizingInt()
    IntSummaryStatistics intSummaryStatistics = employeeList
        .stream()
        .collect(Collectors.summarizingInt(Employee::getAge));
    System.out.println("IntSummaryStatistics for age: " + intSummaryStatistics);

    //Using Collectors.summarizingLong()
    LongSummaryStatistics longSummaryStatistics = employeeList
        .stream()
        .collect(Collectors.summarizingLong(Employee::getLeaves));
    System.out.println("LongSummaryStatistics for leaves: " + longSummaryStatistics);

    //Using Collectors.summarizingDouble()
    DoubleSummaryStatistics doubleSummaryStatistics = employeeList
        .stream()
        .collect(Collectors.summarizingDouble(Employee::getSalary));
    System.out.println("DoubleSummaryStatistics for salary: " + doubleSummaryStatistics);
  }
}
//Employee.java POJO class
package com.javabrahman.java8;
import java.text.DecimalFormat;
public class Employee {
  private String name;
  private Integer age;
  private Double salary;
  private long leaves;

  public Employee(String name, Integer age, Double salary, long leaves) {
    this.name = name;
    this.age = age;
    this.salary = salary;
    this.leaves = leaves;
  }

  //Standard getters & setters for name, age, salary and leaves go here

  //Standard equals() & hashcode() methods go here
}