traceId的生成

public String getTransactionId() {        return TransactionIdUtils.formatString(agentId, agentStartTime, transactionSequence);    }    public static final String TRANSACTION_ID_DELIMITER = "^";    public static String formatString(String agentId, long agentStartTime, long transactionSequence) {        if (agentId == null) {            throw new NullPointerException("agentId must not be null");        }        StringBuilder sb = new StringBuilder(64);        sb.append(agentId);        sb.append(TRANSACTION_ID_DELIMITER);        sb.append(agentStartTime);        sb.append(TRANSACTION_ID_DELIMITER);        sb.append(transactionSequence);        return sb.toString();    }

spanId的生成

public class SpanId {    public static final long NULL = -1;//    private static final Random seed = new Random();    public static long newSpanId() {        final Random random = getRandom();        return createSpanId(random);    }    // Changed to ThreadLocalRandom because unique value per thread will be enough.    // If you need to change Random implementation, modify this method.    private static Random getRandom() {        return ThreadLocalRandomUtils.current();    }    private static long createSpanId(Random seed) {        long id = seed.nextLong();        while (id == NULL) {            id = seed.nextLong();        }        return id;    }    public static long nextSpanID(long spanId, long parentSpanId) {        final Random seed = getRandom();        long newId = createSpanId(seed);        while (newId == spanId || newId == parentSpanId) {            newId = createSpanId(seed);        }        return newId;    }}

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