### Question:
WalletManager { public static void changePassword(String id, String oldPassword, String newPassword) { IMTKeystore keystore = mustFindKeystoreById(id); IMTKeystore newKeystore = (IMTKeystore) keystore.changePassword(oldPassword, newPassword); flushWallet(newKeystore, true); } private  WalletManager(); static void changePassword(String id, String oldPassword, String newPassword); static String exportPrivateKey(String id, String password); static List<KeyPair> exportPrivateKeys(String id, String password); static MnemonicAndPath exportMnemonic(String id, String password); static String exportKeystore(String id, String password); static void removeWallet(String id, String password); static void clearKeystoreMap(); static Wallet importWalletFromKeystore(Metadata metadata, String keystoreContent, String password, boolean overwrite); static Wallet importWalletFromPrivateKey(Metadata metadata, String prvKeyHex, String password, boolean overwrite); static Wallet importWalletFromPrivateKeys(Metadata metadata, String accountName, List<String> prvKeys, List<EOSKeystore.PermissionObject> permissions, String password, boolean overwrite); @Deprecated static Wallet importWalletFromPrivateKey(Metadata metadata, String accountName, String prvKeyHex, String password, boolean overwrite); static Wallet importWalletFromMnemonic(Metadata metadata, @Nullable String accountName, String mnemonic, String path, @Nullable List<EOSKeystore.PermissionObject> permissions, String password, boolean overwrite); static Wallet importWalletFromMnemonic(Metadata metadata, String mnemonic, String path, String password, boolean overwrite); static Wallet findWalletByPrivateKey(String chainType, String network, String privateKey, String segWit); static Wallet findWalletByKeystore(String chainType, String keystoreContent, String password); static Wallet findWalletByMnemonic(String chainType, String network, String mnemonic, String path, String segWit); static Wallet switchBTCWalletMode(String id, String password, String model); static Wallet setAccountName(String id, String accountName); static Wallet mustFindWalletById(String id); static Wallet findWalletByAddress(String type, String address); static void scanWallets(); static KeystoreStorage storage; }### Answer:
@Test public void changePassword() { String m = "victory truck motion great urge loyal supply pipe ship code where hub"; Wallet wallet = WalletManager.importWalletFromMnemonic( new Metadata(ChainType.BITCOIN, Network.TESTNET, "name", "passwordHint"), m, BIP44Util.BITCOIN_TESTNET_PATH, SampleKey.PASSWORD, true); WalletManager.changePassword(wallet.getId(), SampleKey.PASSWORD, "hello1234"); assertEquals(WalletManager.findWalletById(wallet.getId()).verifyPassword("hello1234"), true); MnemonicAndPath result = WalletManager.exportMnemonic(wallet.getId(), "hello1234"); assertEquals(result.getMnemonic(), m); assertEquals(result.getPath(), "m/44'/1'/0'"); wallet.delete("hello1234"); }