J2ME in a Nutshell

Name

Vector

Synopsis

Vector is a collection class that behaves like a variable-length array of objects. A Vector can contain an arbitrary number of Java objects, accessed with an integer position index. The first entry is index 0. Since an entry in a Vector is distinguished only by its index, the same object can appear any number of times in the same Vector.

Entries can be appended to the end of the Vector using the addElement() method. Entries can be inserted at a given index using the insertElementAt() method. The insertElementAt() method causes all elements at that location and higher to be shifted up by one position. An element at a given index can be replaced using the setElementAt() method.

Elements can be removed from a Vector by index or by value. The removeElementAt() method removes the element with the given index, while removeElement(Object obj) removes the element with the lowest index that is equivalent to the object passed in. Both of these methods cause the indices of all elements that follow the removed element to be reduced by 1. The removeAllElements() removes all entries from the Vector.

There are several ways to access the elements in a Vector. The elementAt() returns the element at the specified index. The convenience methods firstElement() and lastElement() return the first and last elements (which will be the same if the Vector has only one element). The elements() method returns an Enumeration that iterates over all of the elements in the Vector in order ...