List<KeyPair> keys = new ArrayList<KeyPair>();
for (String file : files) {
try {
PEMReader r = new PEMReader(new InputStreamReader(new FileInputStream(file)), passwordFinder);
try {
Object o = r.readObject();
if (o instanceof KeyPair) {
keys.add(new KeyPair(((KeyPair)o).getPublic(), null));
} else if (o instanceof PublicKey) {
keys.add(new KeyPair((PublicKey)o, null));
}