For example, If elements 4,5,3 are inserted into an implementation of Set interface, it might store the elements in any order. Set interface does not guarantee any Order. Main difference between Set and SortedSet is - an implementation of SortedSet interface maintains its elements in a sorted order. Both Set and SortedSet do not allow duplicate elements. SortedSet Interface extends the Set Interface. What is the difference between Set and SortedSet? Other important methods in Map Inteface are shown below: interface Mapīoolean containsValue(Object paramObject) Get method allows to get a value from the Map based on the key. Put method allows to add a key, value pair to the Map. A key value pair in a Map interface is called an Entry. Key-value pairs are used in lookup tables, hash tables and configuration files. A key-value pair is a set of linked data items: a key, which is a unique identifier for some item of data, and the value, which is either the data or a pointer to the data. So, it does not inherit any of the methods from the Collection interface.Ī Map interface supports Collections that use a key value pair. List subList(int paramInt1, int paramInt2) Ĭan you briefly explain about the Map Interface?įirst and foremost, Map interface does not extend Collection interface. Listed below are some of the important methods in the List interface (other than those inherited from Collection interface): interface List extends Collectionīoolean addAll(int paramInt, Collection paramCollection) However, We can also use the void add(int position, E paramE) method to insert an element at a specific position. When a new element is inserted without specifying a position, it is inserted at the end of the list of elements. When an element A is inserted into a List (without specifying position) and then another element B is inserted, A is stored before B in the List. Most important thing to remember about a List interface - any implementation of the List interface would maintain the insertion order. In addition, List interface allows operation specifying the position of the element in the Collection. So, it contains all methods defined in the Collection interface. List interface extends Collection interface. interface Collection extends Iterableīoolean containsAll(Collection paramCollection) īoolean addAll(Collection paramCollection) īoolean removeAll(Collection paramCollection) īoolean retainAll(Collection paramCollection) Ĭan you explain briefly about the List Interface? Other important methods defined as part of collection interface are shown below. Size() methods returns number of elements in the collection.

add method allows adding an element to a collection and delete method allows deleting an element from a collection. Most important methods declared in the collection interface are the methods to add and remove an element. What are the important methods that are declared in the Collection Interface? What is difference between fail-safe and fail-fast iterators?.When does a Java collection throw UnsupportedOperationException?.What is initial capacity of a Java Collection?.What is a Lock? How is it different from using synchronized approach?.Explain about CopyOnWrite concurrent collections approach?.Explain about the new concurrent collections in Java?.What is the difference between synchronized and concurrent collections in Java?.What are the static methods present in the Collections class?.Can you give an example of implementation of NavigableMap Interface?.What is a TreeMap? How is different from a HashMap?.What are the different methods in a Hash Map?.What are the different implementations of a Map Interface?.What are the important methods in the NavigableSet interface?.Can you give examples of implementations of NavigableSet?.What is a TreeSet? How is different from a HashSet?.What is a LinkedHashSet? How is different from a HashSet?.Can you give examples of classes that implement the Set Interface?.What is LinkedList? What interfaces does it implement? How is it different from an ArrayList?.What is Vector class? How is it different from an ArrayList?.How do you sort elements in an ArrayList using Comparator interface?.How do you sort elements in an ArrayList using Comparable interface?.How do you iterate around an ArrayList using Iterator?.Can an ArrayList have Duplicate elements?.Explain about ArrayList with an example?.What is difference between Map and SortedMap?.What is the difference between Set and SortedSet?.Can you briefly explain about the Map Interface?.Can you explain briefly about the List Interface?.What are the important methods that are declared in the Collection Interface?.

Collections in java interview questions