Added YdbTracer to keep trace of whole transaction

jdbc/src/main/java/tech/ydb/jdbc/YdbTracer.java

@@ -0,0 +1,89 @@
+package tech.ydb.jdbc;
+
+import java.util.ArrayList;
+import java.util.Date;
+import java.util.List;
+import java.util.concurrent.ThreadLocalRandom;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+
+
+
+/**
+ *
+ * @author Aleksandr Gorshenin
+ */
+public class YdbTracer {
+    private static final Logger LOGGER = Logger.getLogger(YdbTracer.class.getName());
+    private static final ThreadLocal<YdbTracer> LOCAL = new ThreadLocal<>();
+
+    private final Date startDate = new Date();
+    private final long startedAt = System.currentTimeMillis();
+    private final List<Record> records = new ArrayList<>();
+
+    private String txID = null;
+    private boolean isMarked = false;
+    private boolean isClosed = false;
+
+    private class Record {
+        private final long executedAt = System.currentTimeMillis();
+        private final String type;
+        private final String comment;
+
+        public Record(String type, String comment) {
+            this.type = type;
+            this.comment = comment;
+        }
+    }
+
+    public static void clear() {
+        LOCAL.remove();
+    }
+
+    public static YdbTracer current() {
+        YdbTracer tracer = LOCAL.get();
+        if (tracer == null || tracer.isClosed) {
+            tracer = new YdbTracer();
+            LOCAL.set(tracer);
+        }
+
+        return tracer;
+    }
+
+    public void trace(String type, String comment) {
+        records.add(new Record(type, comment));
+    }
+
+    public void setId(String id) {
+        this.txID = id;
+        trace("SET ID", id);
+    }
+
+    public void markToPrint() {
+        this.isMarked = true;
+        trace("MARK TO PRINT", "");
+    }
+
+    public void close() {
+        isClosed = true;
+
+        LOCAL.remove();
+
+        final Level level = isMarked ? Level.INFO : Level.FINE;
+        if (!LOGGER.isLoggable(level) || records.isEmpty()) {
+            return;
+        }
+
+        long finishedAt = System.currentTimeMillis();
+
+        final String id = txID != null ? txID : "UKNOWN-" + ThreadLocalRandom.current().nextLong();
+        LOGGER.log(level, "Trace[{0}] started at {1}", new Object[] { id, startDate });
+        long last = startedAt;
+        for (Record record: records) {
+            long ms = record.executedAt - last;
+            LOGGER.log(level, "Trace[{0}] {1} ms {2}: {3}", new Object[] { id, ms, record.type, record.comment });
+            last = record.executedAt;
+        }
+        LOGGER.log(level, "Trace[{0}] finished in {1} ms", new Object[] { id, finishedAt - startedAt });
+    }
+}