This program demonstrates the use of a map with key type String and value type Employee : Map « Collections Data Structure « Java






  1. Java
  2. Collections Data Structure
  3. Map

This program demonstrates the use of a map with key type String and value type Employee

      
/*
   This program is a part of the companion code for Core Java 8th ed.
   (http://horstmann.com/corejava)

   This program is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation, either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

import java.util.HashMap;
import java.util.Map;

/**
 * This program demonstrates the use of a map with key type String and value type Employee.
 * @version 1.10 2004-08-02
 * @author Cay Horstmann
 */
public class MapTest
{
   public static void main(String[] args)
   {
      Map<String, Employee> staff = new HashMap<String, Employee>();
      staff.put("144-25-5464", new Employee("Amy Lee"));
      staff.put("567-24-2546", new Employee("Harry Hacker"));
      staff.put("157-62-7935", new Employee("Gary Cooper"));
      staff.put("456-62-5527", new Employee("Francesca Cruz"));

      // print all entries

      System.out.println(staff);

      // remove an entry

      staff.remove("567-24-2546");

      // replace an entry

      staff.put("456-62-5527", new Employee("Francesca Miller"));

      // look up a value

      System.out.println(staff.get("157-62-7935"));

      // iterate through all entries

      for (Map.Entry<String, Employee> entry : staff.entrySet())
      {
         String key = entry.getKey();
         Employee value = entry.getValue();
         System.out.println("key=" + key + ", value=" + value);
      }
   }
}

/**
 * A minimalist employee class for testing purposes.
 */
class Employee
{
   /**
    * Constructs an employee with $0 salary.
    * @param n the employee name
    */
   public Employee(String n)
   {
      name = n;
      salary = 0;
   }

   public String toString()
   {
      return "[name=" + name + ", salary=" + salary + "]";
   }

   private String name;
   private double salary;
}








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