KeyStore类如何写入并保存SecretKey,报一个异常..

try
{
char[] password=storepassword.toCharArray();
SecretKeyFactory kf=SecretKeyFactory.getInstance("DESede");
FileOutputStream fos =new java.io.FileOutputStream("E:/test.store");
KeyStore ks = KeyStore.getInstance("JKS");
ks.load(null, storepassword.toCharArray());
DESedeKeySpec desk=new DESedeKeySpec(keys[0].getBytes());
SecretKey mySecretKey=kf.generateSecret(desk);
KeyStore.SecretKeyEntry skEntry =new KeyStore.SecretKeyEntry(mySecretKey);
ks.setEntry(alias[0],skEntry,new PasswordProtection(password));
ks.store(fos,storepassword.toCharArray());
}
catch(Exception e)
{
e.printStackTrace();
}