{"id":7913,"date":"2025-02-07T13:35:33","date_gmt":"2025-02-07T13:35:33","guid":{"rendered":"https:\/\/msgprogramator.sk\/?p=7913"},"modified":"2026-04-01T11:56:29","modified_gmt":"2026-04-01T11:56:29","slug":"java-vector","status":"publish","type":"post","link":"https:\/\/msgprogramator.sk\/en\/java-vector\/","title":{"rendered":"Java Vector: data structure and Vector class (dynamic array) in Java"},"content":{"rendered":"

As part of our series on data structures (collections), we introduce Java Vector<\/strong> for easier data manipulation. As part of our series on data structures,<\/a> we’ll introduce each structure, collection, and class by showing their uses, available methods, advantages and disadvantages, and providing tips on when to use them.<\/p>\n

In today’s section, we will focus on a collection that represents a dynamic array of objects and can increase or decrease its size according to the needs of the application – Vector<\/strong>.<\/p>\n

\"Hierarchy
Hierarchy of inheritance for the Vector collection<\/figcaption><\/figure>\n

Java Vector: introducing the \u201cdynamic object array\u201d data structure in Java<\/h2>\n

Programmers often work with static or dynamic arrays. However, these are fixed and can only store a predetermined number of elements. If the storage capacity of an array is exceeded, we most often have to create a new array – much larger, copy the elements from the old array into it, and delete the old array so that it doesn’t take up memory space unnecessarily.<\/p>\n

And this is what the Vector collection, which automates the whole process in the background, does away with from the programmer’s point of view. Vector is flexibly enlarged when more elements are added to it<\/strong> than its current capacity. If it runs out of capacity to store new elements, the new capacity is calculated as twice the old capacity (assuming the programmer<\/a> doesn’t set a custom capacityIncrement<\/em> increment).<\/p>\n

What is also interesting about this dynamic list is that it can contain objects of different data types.<\/p>\n

The Vector class<\/strong> was introduced in Java 1.2 and is found in the java.util<\/em> package<\/strong>. Although it is currently less used than the similar ArrayList collection<\/strong>, directly in its implementation Vector is synchronized, that is, only one thread can access a given area at a time, while other threads must wait. This feature makes it particularly suitable for use in multithreaded applications.<\/p>\n

Java Vector – constructors<\/h2>\n

To create a Vector instance, we can use one of four constructors.<\/p>\n

1. Creates an empty vector with capacity 10 (default value)<\/p>\n

Vector<E> vector = new Vector<E>();<\/code><\/pre>\n
2. Empty vector with initial capacity size<\/em><\/p>\n
Vector<E> vector = new Vector<E>(int size);<\/code><\/pre>\n
3. Empty vector with initial capacity size<\/em> and increment capacityIncrement<\/em><\/p>\n
The capacity is incremented by capacityIncrement<\/em> when the current capacity is exceeded.<\/p>\n
Vector<E> vector = new Vector<E>(int size, int capacityIncrement);<\/code><\/pre>\n
4. Vector constructed using collection<\/em><\/p>\n
Initializes the vector with elements from the given collection.<\/p>\n
Vector<E> vector = new Vector<E>(Collection<E> collection);<\/code><\/pre>\n
Java Vector – basic operations<\/h2>\n
The basic operations with the Vektor collection include:<\/p>\n