io.neow3j.utils.AddressUtils Maven / Gradle / Ivy
package io.neow3j.utils;
import static io.neow3j.crypto.Hash.hash256;
import static io.neow3j.protocol.Neow3jConfig.getAddressVersion;
import static io.neow3j.utils.ArrayUtils.concatenate;
import static io.neow3j.utils.ArrayUtils.getFirstNBytes;
import static io.neow3j.utils.ArrayUtils.reverseArray;
import io.neow3j.crypto.Base58;
import io.neow3j.crypto.exceptions.AddressFormatException;
import io.neow3j.protocol.Neow3jConfig;
public class AddressUtils {
/**
* Checks whether the given string is a valid Neo address.
*
* Make sure that the address version used in the address is the same as the one configured in
* {@link Neow3jConfig#setAddressVersion(byte)}.
*
* @param address The address to be checked.
* @return whether the address is valid or not.
*/
public static boolean isValidAddress(String address) {
byte[] data;
try {
data = Base58.decode(address);
} catch (AddressFormatException e) {
return false;
}
if (data.length != 25) {
return false;
}
if (data[0] != getAddressVersion()) {
return false;
}
byte[] checksum = hash256(data, 0, 21);
for (int i = 0; i < 4; i++) {
if (data[data.length - 4 + i] != checksum[i]) {
return false;
}
}
return true;
}
/**
* Transforms the given address into its script hash.
*
* @param address The address.
* @return the script hash byte array in big-endian order.
*/
public static byte[] addressToScriptHash(String address) {
if (!isValidAddress(address)) {
throw new IllegalArgumentException("Not a valid NEO address.");
}
byte[] data = Base58.decode(address);
byte[] buffer = new byte[20];
System.arraycopy(data, 1, buffer, 0, 20);
return reverseArray(buffer);
}
/**
* Derives the Neo address from the given script hash.
*
* Make sure that the address version configured in {@link Neow3jConfig#getAddressVersion()}
* matches the blockchain network you are intending the address for.
*
* @param scriptHash The script hash in big-endian order.
* @return the address
*/
public static String scriptHashToAddress(byte[] scriptHash) {
byte[] script = concatenate(getAddressVersion(), reverseArray(scriptHash));
byte[] checksum = getFirstNBytes(hash256(script), 4);
return Base58.encode(concatenate(script, checksum));
}
}