AbstractMap

Removes all elements from this Map , leaving it empty.

This implementation calls entrySet().clear() .

Returns whether this Map contains the specified key.

This implementation iterates its key set, looking for a key that key equals.

Returns whether this Map contains the specified value.

This implementation iterates its entry set, looking for an entry with a value that value equals.

Returns a Set containing all of the mappings in this Map . Each mapping is an instance of Map.Entry . As the Set is backed by this Map , changes in one will be reflected in the other.

Compares this instance with the specified object and indicates if they are equal. In order to be equal, o must represent the same object as this instance using a class-specific comparison. The general contract is that this comparison should be reflexive, symmetric, and transitive. Also, no object reference other than null is equal to null.

The default implementation returns true only if this == o . See Writing a correct equals method if you intend implementing your own equals method.

The general contract for the equals and hashCode() methods is that if equals returns true for any two objects, then hashCode() must return the same value for these objects. This means that subclasses of Object usually override either both methods or neither of them.

This implementation first checks the structure of object . If it is not a map or of a different size, this returns false. Otherwise it iterates its own entry set, looking up each entry's key in object . If any value does not equal the other map's value for the same key, this returns false. Otherwise it returns true.

Returns the value of the mapping with the specified key.

This implementation iterates its entry set, looking for an entry with a key that key equals.

Returns an integer hash code for this object. By contract, any two objects for which equals(Object) returns true must return the same hash code value. This means that subclasses of Object usually override both methods or neither method.

Note that hash values must not change over time unless information used in equals comparisons also changes.

See Writing a correct hashCode method if you intend implementing your own hashCode method.

This implementation iterates its entry set, summing the hashcodes of its entries.

Returns whether this map is empty.

This implementation compares size() to 0.

Returns a set of the keys contained in this Map . The Set is backed by this Map so changes to one are reflected by the other. The Set does not support adding.

This implementation returns a view that calls through this to map. Its iterator transforms this map's entry set iterator to return keys.

Maps the specified key to the specified value.

This base implementation throws UnsupportedOperationException .

Copies every mapping in the specified Map to this Map .

This implementation iterates through map 's entry set, calling put() for each.

Removes a mapping with the specified key from this Map .

This implementation iterates its entry set, removing the entry with a key that key equals.

Returns the number of mappings in this Map .

This implementation returns its entry set's size.

Returns a string containing a concise, human-readable description of this object. Subclasses are encouraged to override this method and provide an implementation that takes into account the object's type and data. The default implementation is equivalent to the following expression:

          getClass().getName() + '@' + Integer.toHexString(hashCode())
         

See Writing a useful toString method if you intend implementing your own toString method.

This implementation composes a string by iterating its entry set. If this map contains itself as a key or a value, the string "(this Map)" will appear in its place.

Returns a Collection of the values contained in this Map . The Collection is backed by this Map so changes to one are reflected by the other. The Collection supports remove(Object) , )">removeAll(Collection ) , )">retainAll(Collection ) , and clear() operations, and it does not support add(E) or )">addAll(Collection ) operations.

This method returns a Collection which is the subclass of AbstractCollection . The iterator() method of this subclass returns a "wrapper object" over the iterator of this Map 's entrySet() . The size() method wraps this Map 's size() method and the contains(Object) method wraps this Map 's containsValue(Object) method.

The collection is created when this method is called at first time and returned in response to all subsequent calls. This method may return different Collection when multiple calls to this method, since it has no synchronization performed.

This implementation returns a view that calls through this to map. Its iterator transforms this map's entry set iterator to return values.

Creates and returns a copy of this Object . The default implementation returns a so-called "shallow" copy: It creates a new instance of the same class and then copies the field values (including object references) from this instance to the new instance. A "deep" copy, in contrast, would also recursively clone nested objects. A subclass that needs to implement this kind of cloning should call super.clone() to create the new instance and then create deep copies of the nested, mutable objects.