consenlabs/token-core-android

a blockchain private key management library on android

Token Core

TokenCore is a blockchain library. TokenCore provides the relatively consistent API that allows you to manage your wallets and sign transactions in BTC, ETH and EOS chains simultaneously. In addition, TokenCore introduces the concept of ‘identity’, you can use the same mnemonic to manage wallets on the three chains.

Installation

Step 1. Add the JitPack repository to your build file Add it in your root build.gradle at the end of repositories:

	allprojects {
		repositories {
			...
			maven { url 'https://jitpack.io' }
		}
	}

Step 2. Add the dependency

dependencies {
	implementation 'com.github.consenlabs:token-core-android:v0.1'
}

Step 3. Add the JAVA8 support to your build.gradle

android {
    ……
    compileOptions {
        sourceCompatibility JavaVersion.VERSION_1_8
        targetCompatibility JavaVersion.VERSION_1_8
    }
   ……
}

Step 4. (Optional) When you wants to debug your app in Android Oreo you shoud add the blow code to your build.gradle. Pls ref to https://issuetracker.google.com/issues/65941637 for more info.

android {
    ……
    packagingOptions {
        exclude 'lib/x86_64/darwin/libscrypt.dylib'
    }
   ……
}

Try the API

Init the storage to store the keystore file

public class MainActivity extends AppCompatActivity implements KeystoreStorage {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        WalletManager.storage = this;
        WalletManager.scanWallets();
    }

    public File getKeystoreDir() {
        return this.getFilesDir();
    }
}

Create new Identity and derive the eth, btc wallets

// You should create or recover Identity first before you create other wallets
// The last param, Metadata.P2WPKH means that the derived btc wallet is a SegWit wallet
Identity identity = Identity.createIdentity("MyFirstIdentity", SampleKey.PASSWORD, SampleKey.PASSWORD_HINT, Network.MAINNET, Metadata.P2WPKH);


Wallet ethereumWallet = identity.getWallets().get(0);
Wallet bitcoinWallet = identity.getWallets().get(1);

Export Wallet

String prvKey = WalletManager.exportPrivateKey(ethereumWallet.getId(), SampleKey.PASSWORD);
System.out.println(String.format("PrivateKey: %s", prvKey));
String mnemonic = WalletManager.exportMnemonic(ethereumWallet.getId(), SampleKey.PASSWORD).getMnemonic();
System.out.println(String.format("Mnemonic: %s", mnemonic));
String json = WalletManager.exportKeystore(ethereumWallet.getId(), SampleKey.PASSWORD);
System.out.println(String.format("Keystore: %s", json));

// output:
// PrivateKey: f653be3f639f45ea1ed3eb152829b6d881ce62257aa873891e06fa9569a8d9aa
// Mnemonic: tide inmate cloud around wise bargain celery cement jungle melody galaxy grocery
// Keystore: {"id":"c7575eba-3ae3-4cc3-86ba-2eb9c6839cad","version":3,"crypto":{"ciphertext":"7083ba3dd5470ba4be4237604625e05fa6b668954d270beb848365cbf6933ec5","mac":"f4f9ea8d42ff348b11fc146c396da446cc975309b3538e08a58c0b218bddd15d","cipher":"aes-128-ctr","cipherparams":{"iv":"db3f523faf4da4f1c6edcd7bc1386879"},"kdf":"pbkdf2","kdfparams":{"dklen":32,"c":10240,"prf":"hmac-sha256","salt":"0ce830e9f888dfe33c31e6cfc444d6f588161c9d4128d4066ee5dfdcbc5d0079"}},"address":"4a1c2072ac67b616e5c578fd9e2a4d30e0158471"}

SignTransaction

EthereumTransaction tran = new EthereumTransaction(BigInteger nonce, BigInteger gasPrice, BigInteger gasLimit, String to, BigInteger value, String data)
TxSignResult result = tran.signTransaction(chainId, SampleKey.PASSWORD, ethereumWallet);
String signedTx = result.getSignedTx(); // This is the signature result which you need to broadcast.
String txHash = result.getTxHash(); // This is txHash which you can use for locating your transaction record

Copyright and License

  Copyright 2018 imToken PTE. LTD.

  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.

Thanks and more info

Thanks bitcoinj, CoreBitcoin and others library.