#1183 - ENH: Add support for transaction profiling

src/main/java/io/ebeaninternal/server/transaction/ProfileStream.java

@@ -0,0 +1,102 @@
+package io.ebeaninternal.server.transaction;
+
+import io.ebeaninternal.api.TxnProfileEventCodes;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.io.ByteArrayOutputStream;
+import java.io.DataOutputStream;
+import java.io.IOException;
+
+/**
+ * A binary encoding of the transaction profiling events.
+ */
+public class ProfileStream implements TxnProfileEventCodes {
+
+  private static final Logger logger = LoggerFactory.getLogger(ProfileStream.class);
+
+  private final int profId;
+  private final long startNanos;
+  private final DataOutputStream out;
+  private final ByteArrayOutputStream profileBuffer;
+
+  public ProfileStream(int profId) {
+    this.profId = profId;
+    this.startNanos = System.nanoTime();
+    this.profileBuffer = new ByteArrayOutputStream(200);
+    this.out = new DataOutputStream(profileBuffer);
+    try {
+      out.writeLong(System.currentTimeMillis());
+      out.writeInt(profId);
+    } catch (IOException e) {
+      throw new RuntimeException("Unexpected error starting transaction profiling", e);
+    }
+  }
+
+  /**
+   * Return the time offset from the beginning of the transaction.
+   */
+  public int offset() {
+    // int max of 2,147,483,648 as micros = 35 minutes
+    // use 10_000 to get 100th of millis to max at 357 minutes (almost 6 hours)
+    // not micros so we can reasonably use int rather than long
+    return (int)((System.nanoTime() - startNanos) / 10_000L);
+  }
+
+  /**
+   * Add the commit/rollback event.
+   */
+  public void addEvent(byte event, int startOffset) {
+    try {
+      out.writeByte(event);
+      out.writeInt(startOffset);
+      out.writeInt(offset() - startOffset);
+    } catch (IOException e) {
+      logger.error("Error writing event to transaction profiling", e);
+    }
+  }
+
+  /**
+   * Add a query execution event.
+   */
+  public void addQueryEvent(byte event, int offset, short beanTypeId, int beanCount, short queryId) {
+    add(event, offset, beanTypeId, beanCount, queryId);
+  }
+
+  /**
+   * Add a persist event.
+   */
+  public void addEvent(byte event, int offset, short beanTypeId, int beanCount) {
+    add(event, offset, beanTypeId, beanCount, (short)0);
+  }
+
+  private void add(byte event, int offset, short beanTypeId, int beanCount, short queryId) {
+    try {
+      out.writeByte(event);
+      out.writeInt(offset);
+      out.writeInt(offset() - offset);
+      out.writeShort(beanTypeId);
+      out.writeInt(beanCount);
+      out.writeShort(queryId);
+    } catch (IOException e) {
+      logger.error("Error writing event to transaction profiling", e);
+    }
+  }
+
+  /**
+   * End the transaction profiling.
+   */
+  public void end(TransactionManager manager) {
+    try {
+      long totalMicros = ((System.nanoTime() - startNanos) / 1_000L);
+      out.writeByte(EVT_END);
+      out.writeLong(totalMicros);
+      out.flush();
+      out.close();
+      manager.profileCollect(new TransactionProfile(profId, totalMicros, profileBuffer.toByteArray()));
+    } catch (IOException e) {
+      logger.error("Error flushing and collecting profiling", e);
+    }
+  }
+
+}