scouter.util.zipkin.HexCodec Maven / Gradle / Ivy
/*
* This source is from OpenZipkin.
*
* Copyright 2015-2018 The OpenZipkin Authors
*
* 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 scouter.util.zipkin;
/**
* @author Gun Lee ([email protected]) on 24/11/2018
*/
public class HexCodec {
/**
* Parses a 1 to 32 character lower-hex string with no prefix into an unsigned long, tossing any
* bits higher than 64.
*/
public static long lowerHexToUnsignedLong(String lowerHex) {
int length = lowerHex.length();
if (length < 1 || length > 32) throw isntLowerHexLong(lowerHex);
// trim off any high bits
int beginIndex = length > 16 ? length - 16 : 0;
return lowerHexToUnsignedLong(lowerHex, beginIndex);
}
/**
* Parses a 16 character lower-hex string with no prefix into an unsigned long, starting at the
* spe index.
*/
public static long lowerHexToUnsignedLong(String lowerHex, int index) {
long result = 0;
for (int endIndex = Math.min(index + 16, lowerHex.length()); index < endIndex; index++) {
char c = lowerHex.charAt(index);
result <<= 4; // result = result << 4
if (c >= '0' && c <= '9') {
result |= c - '0'; // result = result | c - '0'
} else if (c >= 'a' && c <= 'f') {
result |= c - 'a' + 10;
} else {
throw isntLowerHexLong(lowerHex);
}
}
return result;
}
static NumberFormatException isntLowerHexLong(String lowerHex) {
throw new NumberFormatException(
lowerHex + " should be a 1 to 32 character lower-hex string with no prefix");
}
HexCodec() {}
}