/**
* compute a frequency table from an InputStream and save a compacted representation of this table
* in the system preferences. (To be used later by @see #useStandardTable(String) )
*
* @param name name to give the table.
* @param in InputStream
* @return true on success
* @throws Exception
*/
public static boolean CreateStandardTableFromStream(String name, InputStream in)
throws Exception {
int[] tbl = new int[TABLESIZE];
while (in.available() != 0) {
int c = in.read();
tbl[c]++;
}
byte[] dest = HuffmanTree.compactTable(tbl);
Preferences pref = Preferences.userNodeForPackage(Huff.class);
Preferences node = pref.node("StandardTables");
node.putByteArray(name, dest);
pref.flush();
return true;
}
/**
* Import a compaced frequency table from the system preferences (In windows from the registry
* HKLM/JavaSoft/Prefs/ch/rgw/tools/Compress/StandardTables, in Linux from ~/.prefs)
*
* @param name Name of the table in the registry. If no table with this name is found, the default
* table (TextDeutsch) is returned.
* @return the table
*/
public static int[] useStandardTable(String name) {
Preferences pr = Preferences.userNodeForPackage(Huff.class);
Preferences node = pr.node("StandardTables");
byte[] res = node.getByteArray(name, TextDeutsch);
return HuffmanTree.expandTable(res);
}