IPV6Mask.java

/*
 * Copyright (C) 2020-2023 Dipl.-Inform. Kai Hofmann. All rights reserved!
 */
package de.powerstat.validation.values;


import java.util.Objects;

import de.powerstat.validation.interfaces.IValueObject;


/**
 * IP V6 mask.
 *
 * Not DSGVO relevant.
 */
public final class IPV6Mask implements Comparable<IPV6Mask>, IValueObject
 {
  /* *
   * Cache for singletons.
   */
  // private static final Map<Integer, IPV6Mask> CACHE = new WeakHashMap<>();

  /**
   * Prefix length.
   */
  private final int length;


  /**
   * Constructor.
   *
   * @param length Prefix length (0-128)
   * @throws IndexOutOfBoundsException if the prefix length is &lt; 0 or &gt; 128
   */
  private IPV6Mask(final int length)
   {
    super();
    if ((length < 0) || (length > 128))
     {
      throw new IndexOutOfBoundsException("Netmask prefix < 0 or > 128"); //$NON-NLS-1$
     }
    this.length = length;
   }


  /**
   * IPV6Mask factory.
   *
   * @param length IP V6 prefix length (0-128)
   * @return IPV6Mask object
   */
  public static IPV6Mask of(final int length)
   {
    /*
    synchronized (IPV6Mask.class)
     {
      IPV6Mask obj = IPV6Mask.CACHE.get(length);
      if (obj != null)
       {
        return obj;
       }
      obj = new IPV6Mask(length);
      IPV6Mask.CACHE.put(Integer.valueOf(length), obj);
      return obj;
     }
    */
    return new IPV6Mask(length);
   }


  /**
   * IPV6Mask factory.
   *
   * @param value IP V6 prefix length string (0-128)
   * @return IPV6Mask object
   */
  public static IPV6Mask of(final String value)
   {
    return of(Integer.parseInt(value));
   }


  /**
   * Returns the value of this IPV6Mask as an int.
   *
   * @return The numeric value represented by this object after conversion to type int (0-128).
   */
  public int intValue()
   {
    return this.length;
   }


  /**
   * Returns the value of this IPV6Mask as an String.
   *
   * @return The numeric value represented by this object after conversion to type String (0-128).
   */
  @Override
  public String stringValue()
   {
    return String.valueOf(this.length);
   }


  /**
   * Calculate hash code.
   *
   * @return Hash
   * @see java.lang.Object#hashCode()
   */
  @Override
  public int hashCode()
   {
    return Integer.hashCode(this.length);
   }


  /**
   * Is equal with another object.
   *
   * @param obj Object
   * @return true when equal, false otherwise
   * @see java.lang.Object#equals(java.lang.Object)
   */
  @Override
  public boolean equals(final Object obj)
   {
    if (this == obj)
     {
      return true;
     }
    if (!(obj instanceof IPV6Mask))
     {
      return false;
     }
    final IPV6Mask other = (IPV6Mask)obj;
    return this.length == other.length;
   }


  /**
   * Returns the string representation of this IPV4Address.
   *
   * The exact details of this representation are unspecified and subject to change, but the following may be regarded as typical:
   *
   * "IPV6Mask[length=128, mask=]"
   *
   * @return String representation of this IPV4Mask
   * @see java.lang.Object#toString()
   */
  @Override
  public String toString()
   {
    final var builder = new StringBuilder(17);
    builder.append("IPV6Mask[length=").append(this.length).append(']'); //$NON-NLS-1$
    return builder.toString();
   }


  /**
   * Compare with another object.
   *
   * @param obj Object to compare with
   * @return 0: equal; 1: greater; -1: smaller
   * @see java.lang.Comparable#compareTo(java.lang.Object)
   */
  @Override
  public int compareTo(final IPV6Mask obj)
   {
    Objects.requireNonNull(obj, "obj"); //$NON-NLS-1$
    return Integer.compare(this.length, obj.length);
   }

 }