dcutils.rpg.Vital Maven / Gradle / Ivy

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package dcutils.rpg;

/**
 * The Vital class represents things like hit points, magic points.

 * E.g.:
Vital hp = new Vital(50);<br/>
if(hp.reduce(num)) {<br/>
   System.out.println("still alive");<br/>
} else {<br/>
   System.out.println("dead");<br/>
} // END if/else

 * @author dca
 */
public class Vital {
   /** The maximum value this vital can be set to.
 */
   private int max;

   /** The value which this vital is currently set.
 */
   private int cur;

   /**
    * The constructor initializes the max and cur values to match the supplied maximum value.

    * @param max The supplied maximum value.

    */
   public Vital(int max) {
      max(max);
      cur(max);
   } // END constructor

   /**
    * The constructor initializes the max and cur values to match the supplied maximum and current values respectively.

    * @param max The supplied maximum value.

    * @param cur the supplied current value.

    */
   public Vital(int max, int cur) {
      max(max);
      cur(max);
   } // END constructor

   /**
    * Returns the maximum value of this vital.

    * @return max The maximum value of this vital.

    */
   public int max() {
      return max;
   } // END max getter

   /**
    * Sets the maximum value of this vital.

    * @param num The supplied maximum value.

    * @return Vital A reference to this vital.

    * @see #check()
    */
   public Vital max(int num) {
      this.max = num;
      check();
      return this;
   } // END max setter

   /**
    * Returns the current value of this vital.

    * @return cur The current value of this vital.

    */
   public int cur() {
      return cur;
   } // END cur getter

   /**
    * Sets the current value of this vital.

    * @param num The supplied current value.

    * @return Vital A reference to this vital.

    * @see #check()
    */
   public Vital cur(int num) {
      this.cur = num;
      check();
      return this;
   } // END cur setter

   /**
    * Sets the current value of this vital to the maximum value.

    * @return Vital A reference to this vital.

    */
   public Vital refresh() {
      cur = max;
      return this;
   } // END refresh

   /**
    * Adds the supplied amount to the current value of this vital, as long as the amount is positive.

    * Otherwise, nothing happens.

    * @param amt The supplied amount.  Cannot be negative.

    * @return Vital A reference to this vital.

    * @see #check()
    */
   public Vital refresh(int amt) {
      // disallow negative param and overflow
      if(0 < amt && 0 < cur + amt) {
         cur += amt;
         check();
      } // END if
      return this;
   } // END refresh

   /**
    * Subtracts the supplied amount to the current value of this vital, as long as the amount is positive.

    * Otherwise, nothing happens.

    * @param amt The supplied amount.  Cannot be negative.

    * @return Vital A reference to this vital.

    * @see #check()
    */
   public boolean reduce(int amt) {
      // disallow negative param
      if(0 < amt) {
         cur -= amt;
         check();
      } // END if
      return 0 < cur;
   } // END reduce

   /**
    * Adds the supplied amount to the maximum value of this vital, as long as the amount is positive.

    * Otherwise, nothing happens.

    * @param amt The supplied amount.  Cannot be negative.

    * @return Vital A reference to this vital.

    */
   public Vital increase(int amt) {
      // disallow negative param and overflow
      if(0 < amt && 0 < max + amt) {
         max += amt;
      } // END if
      return this;
   } // END increase

   /**
    * Checks current and maximum values of this vital to make sure they are both positive and the current value is <= to the maximum value.

    * Called by other methods of this class, usually after a change to either cur or max has occurred.

    * If either cur or max goes negative, they will be set to zero.

    * If cur is found to be greater than max, then cur will be set to max.

    * Generally, none of these cases should occur since negative parameter values are checked in their respective methods.

    */
   private void check() {
      if(cur < 0) cur = 0;
      if(max < 0) max = 0;
      if(cur > max) cur = max;
   } // END check

   /**
    * Returns a string containing the current value over the maximum value.

    * I.e.: cur/max

    * @return String cur/max

    */
   @Override
   public String toString() {
      return String.format("%d/%d", cur, max);
   } // END toString

   /**
    * Creates a hash code for this vital object.

    * The hash code uses prime numbers and max and cur

    * @return integer The hash code.

    */
   @Override
   public int hashCode() {
      int result = 1;

      result = 151 * result + max;
      result = 151 * result + cur;

      return result;
   } // END hashCode

   /**
    * Decides if an object is equal to this vital.

    * In order for an object to be equal to this vital:

    * the object must also be a vital, must not be null, and cur and max must be the same as this vital's.

    * @param obj The item to check for value equality.

    * @return True or false

    */
   @Override
   public boolean equals(Object obj) {
      if(this == obj)                       return true;
      if(null == obj)                       return false;
      if(this.getClass() != obj.getClass()) return false;
      Vital v = (Vital)obj;
      return (this.max == v.max && this.cur == v.cur);
   } // END equals
} // END class Vital