Generic Object Type in Java

Generic Object Type in Java . In this Article i will explain what is a Generic Object in Java by stepping through the Sample code created by me.

What is a Java Generic Class

Java Generic Class, restrict the Type of related class which can only be used within a Class.
The Generics functionality provide compile-time type safety that allows programmers to catch invalid types during compile time.

The Sample Code

The Sample Code consist of 4 class:

gameCharacter
armory
weaponry
recruitSoldier

Class gameCharacter

package genericExample;
 
public class gameCharacter <T,A>{
     
    // Types of Input
     
    T weapon;
    A armor;
     
    // THis is a Constructor
     
    public gameCharacter(T weapon, A armor) {
        super();
        this.weapon = weapon;
        this.armor = armor;
    }
 
    // Get Info ( armor)
     
    public A getArmor() {
        return armor;
    }
 
   // Set Info ( armor)
 
    public void setArmor(A armor) {
        this.armor = armor;
    }
 
    // Get Info ( armor)
     
     public T getWeapon() {
        return weapon;
    }
      
    // Set Info ( armor)
 
    public void setWeapon(T weapon) {
        this.weapon = weapon;
    }
 
}

Class armory

package genericExample;
 
public class armory {
     
     
    public String armorName;
     
    // This is a constructor
    public armory(String armorName) {
        super();
        this.armorName = armorName;
    }
     
    // Get Info
     
    public String getArmorName() {
        return armorName;
    }
     
    // Set Info
 
    public void setArmorName(String armorName) {
        this.armorName = armorName;
    }
 
     
 
}

Class weaponry

package genericExample;
 
public class weaponry {
     
    public String weaponName;
     
    //This is a Constructor
 
    public weaponry(String weaponName) {
        super();
        this.weaponName = weaponName;
    }
     
    //Get Info
 
    public String getWeaponName() {
        return weaponName;
    }
     
    // Set Info
 
    public void setWeaponName(String weaponName) {
        this.weaponName = weaponName;
    }
 
}

Class recruitSoldier

package genericExample;
 
public class recruitSoldier {
    public static void main(String[] args) {
         
    weaponry sacredSword = new weaponry("Sword Of Gray Skull");
    armory noArmor = new armory("Naked");
     
    gameCharacter<weaponry,armory> Heman = new gameCharacter<weaponry,armory>(sacredSword,noArmor);
             
    String HemanWeapon  = Heman.weapon.getWeaponName();
     
    String HemanArmor = Heman.armor.getArmorName();
 
    System.out.println("Heman owns a  weapon  named "+HemanWeapon);
     
    System.out.println("Heman Armor is  "+HemanArmor);
 
    }
     
}

The Explanation

Initially i have created a class called “gameCharacter”
This Class only accept 2 types “”
T for weapon type , A for armor type
Then i created a Constructor/ getter and setter for “gameCharacter “
The Second and third class which i created were the “weaponry and armory ” class
Constructor, Getter and Setter were created for both class
The final class i created was “recruitSoldier ” Class this class will be used to access the ” gameCharacter , armory, weaponry” class
“weaponry sacredSword = new weaponry(“Sword Of Gray Skull”); ” Create a new weapon object named “sacredSword” and pass a name to the new Weapon “”Sword Of Gray Skull””
“armory noArmor = new armory(“Naked”); ” Create a new amory object named “noArmor” and pass a name to the new armor”Naked”
” gameCharacter Heman = new gameCharacter(sacredSword,noArmor);”Cretate a new gameCharacter called” Heman , equipped with the new object Type being created above
” String HemanWeapon = Heman.weapon.getWeaponName(); ” Retrieve the Name of the Weapon Assign to Heman
” String HemanArmor = Heman.armor.getArmorName(); ” Retrieve the Name of the Armor Assign to Heman
Finally print out Heman weapon and armor

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