Interface Map<K,V>

    • Method Summary

      All Methods Instance Methods Abstract Methods 
      Modifier and Type Method and Description
      java.lang.Iterable<Entry<K,V>> entrySet()
      Returns an iterable collection of all key-value entries of the map.
      V get(K key)
      Returns the value associated with the specified key, or null if no such entry exists.
      boolean isEmpty()
      Tests whether the map is empty.
      V put(K key, V value)
      Associates the given value with the given key.
      V remove(K key)
      Removes the entry with the specified key, if present, and returns its associated value.
      int size()
      Returns the number of entries in the map.
    • Method Detail

      • size

        int size()
        Returns the number of entries in the map.
        Returns:
        number of entries in the map
      • isEmpty

        boolean isEmpty()
        Tests whether the map is empty.
        Returns:
        true if the map is empty, false otherwise
      • get

        V get(K key)
        Returns the value associated with the specified key, or null if no such entry exists.
        Parameters:
        key - the key whose associated value is to be returned
        Returns:
        the associated value, or null if no such entry exists
      • put

        V put(K key,
              V value)
        Associates the given value with the given key. If an entry with the key was already in the map, this replaces the previous value with the new one and returns the old value. Otherwise, a new entry is added and null is returned.
        Parameters:
        key - key with which the specified value is to be associated
        value - value to be associated with the specified key
        Returns:
        the previous value associated with the key (or null, if no such i entry)
      • remove

        V remove(K key)
        Removes the entry with the specified key, if present, and returns its associated value. Otherwise does nothing and returns null.
        Parameters:
        key - the key whose entry is to be removed from the map
        Returns:
        the previous value associated with the removed key, or null if no such entry exists
      • entrySet

        java.lang.Iterable<Entry<K,V>> entrySet()
        Returns an iterable collection of all key-value entries of the map.
        Returns:
        iterable collection of the map's entries