StringBuffer

A StringBuffer is a Java class used for in-place manipulation of Strings.

From the 1.4.2 JavaDoc:

"A string buffer implements a mutable sequence of characters. A string buffer is like a String, but can be modified. At any point in time it contains some particular sequence of characters, but the length and content of the sequence can be changed through certain method calls."

J2SE 5.0 offers an alternative to StringBuffer: java.lang.StringBuilder

See AlwaysUseStringBufferMisconception for a discussion on when to use StringBuffers.

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