CSIS 110 – Lecture 36
Announcements
Part 2 of the last programming assignment is on the course web site.
I have put my recent notes on-line also.
String and StringBuffer
Let’s go back a revisit the String class. What are some methods provided by this class?
What do methods such as toUpperCase and toLowerCase do? They return new Strings –
the original String is unchanged.
Strings are said to be immutable – once you have created one, you can't modify it. (You
can change what the String references, but you can't modify the String itself).
The StringBuffer class is similar to String, except that StringBuffer objects can be
modified. Let's look at some methods provided by the StringBuffer class:
append – add some characters to the end of the StringBuffer
insert – insert characters in the middle of the StringBuffer
setCharAt – change the character at position p to a new value
deleteCharAt – delete the character at position p
toString – return a String representation of the StringBuffer
Also has methods like the String class: length, charAt.
Constructor: unlike Strings, we can only create StringBuffer objects using the
constructor:
StringBuffer()
StringBuffer( String s )
