org.apache.rocketmq.shaded.io.opentelemetry.api.trace.SpanId Maven / Gradle / Ivy
/*
* Copyright The OpenTelemetry Authors
* SPDX-License-Identifier: Apache-2.0
*/
package org.apache.rocketmq.shaded.io.opentelemetry.api.trace;
import org.apache.rocketmq.shaded.io.opentelemetry.api.internal.OtelEncodingUtils;
import org.apache.rocketmq.shaded.io.opentelemetry.api.internal.TemporaryBuffers;
import org.apache.rocketmq.shaded.io.opentelemetry.api.internal.ValidationUtil;
import javax.annotation.concurrent.Immutable;
/**
* Helper methods for dealing with a span identifier. A valid span identifier is a 16 character
* lowercase hex (base16) String, where at least one of the characters is not a "0".
*
* There are two more other representation that this class helps with:
*
*
* - Bytes: a 8-byte array, where valid means that at least one of the bytes is not `\0`.
*
- Long: a {@code long} value, where valid means that the value is non-zero.
*
*/
@Immutable
public final class SpanId {
private static final int BYTES_LENGTH = 8;
private static final int HEX_LENGTH = 2 * BYTES_LENGTH;
private static final String INVALID = "0000000000000000";
private SpanId() {}
/**
* Returns the length of the lowercase hex (base16) representation of the {@code SpanId}.
*
* @return the length of the lowercase hex (base16) representation of the {@code SpanId}.
*/
public static int getLength() {
return HEX_LENGTH;
}
/**
* Returns the invalid {@code SpanId} in lowercase hex (base16) representation. All characters are
* "0".
*
* @return the invalid {@code SpanId} lowercase in hex (base16) representation.
*/
public static String getInvalid() {
return INVALID;
}
/**
* Returns whether the span identifier is valid. A valid span identifier is a 16 character hex
* String, where at least one of the characters is not a '0'.
*
* @return {@code true} if the span identifier is valid.
*/
public static boolean isValid(CharSequence spanId) {
return spanId != null
&& spanId.length() == HEX_LENGTH
&& !INVALID.contentEquals(spanId)
&& OtelEncodingUtils.isValidBase16String(spanId);
}
/**
* Returns the lowercase hex (base16) representation of the {@code SpanId} converted from the
* given bytes representation, or {@link #getInvalid()} if input is {@code null} or the given byte
* array is too short.
*
* It converts the first 8 bytes of the given byte array.
*
* @param spanIdBytes the bytes (8-byte array) representation of the {@code SpanId}.
* @return the lowercase hex (base16) representation of the {@code SpanId}.
*/
public static String fromBytes(byte[] spanIdBytes) {
if (spanIdBytes == null || spanIdBytes.length < BYTES_LENGTH) {
ValidationUtil.log("spanIdBytes is null or too short");
return INVALID;
}
char[] result = TemporaryBuffers.chars(HEX_LENGTH);
OtelEncodingUtils.bytesToBase16(spanIdBytes, result, BYTES_LENGTH);
return new String(result, 0, HEX_LENGTH);
}
/**
* Returns the lowercase hex (base16) representation of the {@code SpanId} converted from the
* given {@code long} value representation.
*
*
There is no restriction on the specified values, other than the already established validity
* rules applying to {@code SpanId}. Specifying 0 for the long value will effectively return
* {@link #getInvalid()}.
*
*
This is equivalent to calling {@link #fromBytes(byte[])} with the specified value stored as
* big-endian.
*
* @param id {@code long} value representation of the {@code SpanId}.
* @return the lowercase hex (base16) representation of the {@code SpanId}.
*/
public static String fromLong(long id) {
if (id == 0) {
return getInvalid();
}
char[] result = TemporaryBuffers.chars(HEX_LENGTH);
OtelEncodingUtils.longToBase16String(id, result, 0);
return new String(result, 0, HEX_LENGTH);
}
}