Save and load public/private RSA key on file

Question

hi
i'm triyng to save and load an RSA key to a file
i generate the keys:
        KeyPairGenerator generator=null;
        KeyPair coppia=null;
        PrivateKey c_privata=null;
        PublicKey c_pubblica=null;
            generator=KeyPairGenerator.getInstance("RSA");
            //imposto la dimensione
            generator.initialize(1024);
            //genero le 2 chiavi
            coppia=generator.genKeyPair();
            //imposto la privata
            c_privata=coppia.getPrivate();
            //imposo la pubblica
            c_pubblica=coppia.getPublic();
//i save the key
        FileOutputStream file = new FileOutputStream("key");
        file.write(c_pubblica.getEncoded());
        file.close();and then i use another program that imports the key:
   Key chiave=null;
   FileInputStream file=new FileInputStream("key");
   byte[]byte_chiave=new byte[162];
             X509EncodedKeySpec chiave_spec = new X509EncodedKeySpec(byte_chiave);
            KeyFactory keyFactory = KeyFactory.getInstance("RSA");
            chiave = keyFactory.generatePublic(chiave_spec);but when i try to reload he key i get:
java.security.InvalidKeyException: IOException : DER input, Integer tag error
where am i wrong?
thanks

Answer 1

sorry...
this is the correct code:
        Key chiave=null;
        FileInputStream file=new FileInputStream(path);
        byte[]byte_chiave=new byte[file.available()];
        System.out.println("leggo: "+file.read(byte_chiave));
        X509EncodedKeySpec chiave_spec = new X509EncodedKeySpec(byte_chiave);
        KeyFactory keyFactory = KeyFactory.getInstance("RSA");
        chiave = keyFactory.generatePublic(chiave_spec);