org.fisco.bcos.sdk.v3.utils.Hex Maven / Gradle / Ivy
/**
* Copyright 2014-2020 [fisco-dev]
*
* 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.
*/
package org.fisco.bcos.sdk.v3.utils;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.util.Objects;
import org.fisco.bcos.sdk.v3.utils.exceptions.DecoderException;
import org.fisco.bcos.sdk.v3.utils.exceptions.EncoderException;
/** Utility class for converting hex data to bytes and back again. */
public class Hex {
private Hex() {}
private static final HexEncoder encoder = new HexEncoder();
public static boolean hasHexPrefix(String data) {
return (data != null) && (data.startsWith("0x") || data.startsWith("0X"));
}
public static String addPrefix(String data) {
if (Objects.isNull(data)) {
return null;
}
if (data.startsWith("0x")) {
return data;
}
return "0x" + data;
}
public static String trimPrefix(String data) {
if (Objects.nonNull(data) && data.startsWith("0x")) {
return data.substring(2);
}
return data;
}
public static String toHexStringWithPrefix(byte[] data) {
return addPrefix(toHexString(data, 0, data.length));
}
public static String toHexStringWithPrefixNullable(byte[] data, String defaultValue) {
return addPrefix(toHexStringMaybeNullData(data, defaultValue));
}
public static String toHexStringMaybeNullData(byte[] data, String defaultValue) {
if (Objects.isNull(data)) {
return defaultValue;
}
return toHexString(data, 0, data.length);
}
public static String toHexString(byte[] data) {
return toHexString(data, 0, data.length);
}
public static String toHexString(byte[] data, int off, int length) {
byte[] encoded = encode(data, off, length);
return StringUtils.fromByteArray(encoded);
}
/**
* encode the input data producing a Hex encoded byte array.
*
* @param data the input data
* @return a byte array containing the Hex encoded data.
*/
public static byte[] encode(byte[] data) {
return encode(data, 0, data.length);
}
/**
* encode the input data producing a Hex encoded byte array.
*
* @param data the input byte array
* @param off the offset of the data to be converted
* @param length the length of the data to be converted
* @return a byte array containing the Hex encoded data.
*/
public static byte[] encode(byte[] data, int off, int length) {
ByteArrayOutputStream bOut = new ByteArrayOutputStream();
try {
encoder.encode(data, off, length, bOut);
} catch (Exception e) {
throw new EncoderException("exception encoding Hex string: " + e.getMessage(), e);
}
return bOut.toByteArray();
}
/**
* Hex encode the byte data writing it to the given output stream.
*
* @param data the byte array
* @param out the output stream
* @throws IOException the I/O exception
* @return the number of bytes produced.
*/
public static int encode(byte[] data, OutputStream out) throws IOException {
return encoder.encode(data, 0, data.length, out);
}
/**
* Hex encode the byte data writing it to the given output stream.
*
* @param data the byte array
* @param off the offset of the data to be converted
* @param length the length of the data to be converted
* @param out the output stream
* @throws IOException the I/O exception
* @return the number of bytes produced.
*/
public static int encode(byte[] data, int off, int length, OutputStream out)
throws IOException {
return encoder.encode(data, off, length, out);
}
/**
* decode the Hex encoded input data. It is assumed the input data is valid.
*
* @param data the input byte array
* @return a byte array representing the decoded data.
*/
public static byte[] decode(byte[] data) {
ByteArrayOutputStream bOut = new ByteArrayOutputStream();
try {
encoder.decode(data, 0, data.length, bOut);
} catch (Exception e) {
throw new DecoderException("exception decoding Hex data: " + e.getMessage(), e);
}
return bOut.toByteArray();
}
/**
* decode the Hex encoded String data - whitespace will be ignored.
*
* @param data the input byte array
* @return a byte array representing the decoded data.
*/
public static byte[] decode(String data) {
if (data.startsWith("0x") || data.startsWith("0X")) {
return Hex.decodeInner(data.substring(2));
} else {
return Hex.decodeInner(data);
}
}
private static byte[] decodeInner(String data) {
ByteArrayOutputStream bOut = new ByteArrayOutputStream();
try {
encoder.decode(data, bOut);
} catch (Exception e) {
throw new DecoderException("exception decoding Hex string: " + e.getMessage(), e);
}
return bOut.toByteArray();
}
/**
* decode the Hex encoded String data writing it to the given output stream, whitespace
* characters will be ignored.
*
* @param data the input byte array
* @param out the output stream
* @throws IOException the I/O exception
* @return the number of bytes produced.
*/
public static int decode(String data, OutputStream out) throws IOException {
return encoder.decode(data, out);
}
}