java.io.File.list()

public String[] list(FilenameFilter filter)

Returns an array of strings naming the files
and directories in the directory denoted by this abstract pathname that satisfy
the specified filter. The behavior of this method is the same as that of the list()
method, except that the strings in the returned array must satisfy the filter. If
the given filter is null then all names are accepted. Otherwise, a name satisfies
the filter if and only if the value true results when the FilenameFilter.accept
java.io.File, java.lang.String) method of the filter is invoked on this abstract
pathname and the name of a file or directory in the directory that it denotes. 

Parameters:
filter - A filename filter 
Returns:
An array of strings naming the files and directories in the directory denoted by
this abstract pathname that were accepted by the given filter. The array will
be empty if the directory is empty or if no names were accepted by the filter.
Returns null if this abstract pathname does not denote a directory, or if an I/O
error occurs. 
Throws: 
SecurityException - If a security manager exists and its
SecurityManager.checkRead(java.lang.String) method denies read access to
the directory