more jmx stuff

utils/src/com/cloud/utils/db/Transaction.java

@@ -29,6 +29,7 @@ import java.util.Iterator;
 import java.util.LinkedList;
 import java.util.List;
 import java.util.Properties;
+import java.util.concurrent.atomic.AtomicLong;
 
 import javax.sql.DataSource;
 
@@ -77,8 +78,19 @@ public class Transaction {
     public static final short CLOUD_DB = 0;
     public static final short USAGE_DB = 1;
     public static final short CONNECTED_DB = -1;
+    
+    private static final TransactionMBeanImpl s_mbean = new TransactionMBeanImpl();
+    static {
+        try {
+            JmxUtil.registerMBean("Transaction", "Transaction", s_mbean);
+        } catch (Exception e) {
+            s_logger.error("Unable to register mbean for transaction", e);
+        }
+    }
 
     private final LinkedList<StackElement> _stack;
+    private static AtomicLong s_id = new AtomicLong();
+    private long _id;
     
     private final LinkedList<Pair<String, Long>> _lockTimes = new LinkedList<Pair<String, Long>>();
 
@@ -89,6 +101,7 @@ public class Transaction {
     private long _txnTime;
     private Statement _stmt;
     private final Merovingian _lockMaster;
+    private String _creator;
     
     private Transaction _prev = null;
     
@@ -125,12 +138,8 @@ public class Transaction {
         tls.set(txn);
         
         txn.takeOver(name, true);
-        try {
-            s_logger.debug("Registering txn" + System.identityHashCode(txn));
-            JmxUtil.registerMBean("Transaction", "txn" + System.identityHashCode(txn), new TransactionMBeanImpl(txn));
-        } catch (Exception e) {
-            s_logger.error("Unable to register MBean", e);
-        }
+        s_logger.debug("Registering txn" + txn.getId());
+        s_mbean.addTransaction(txn);
         return txn;
     }
     
@@ -162,12 +171,8 @@ public class Transaction {
 
         txn.takeOver(name, false);
         if (isNew) {
-            try {
-                s_logger.debug("Registering txn" + System.identityHashCode(txn));
-                JmxUtil.registerMBean("Transaction", "txn" + System.identityHashCode(txn), new TransactionMBeanImpl(txn));
-            } catch (Exception e) {
-                s_logger.error("Unable to register MBean", e);
-            }
+            s_logger.debug("Registering txn" + txn.getId());
+            s_mbean.addTransaction(txn);
         }
         return txn;
     }
@@ -307,6 +312,16 @@ public class Transaction {
         _txn = false;
         _dbId = databaseId;
         _lockMaster = forLocking ? null : new Merovingian(_dbId);
+        _id = s_id.incrementAndGet();
+        _creator = Thread.currentThread().getName();
+    }
+    
+    public String getCreator() {
+        return _creator;
+    }
+    
+    public long getId() {
+        return _id;
     }
 
     public String getName() {
@@ -601,12 +616,8 @@ public class Transaction {
         if(this._dbId == CONNECTED_DB) {
 	        tls.set(_prev);
 	        _prev = null;
-            try {
-                s_logger.debug("Unregistering txn" + System.identityHashCode(this));
-                JmxUtil.unregisterMBean("Transaction", "txn" + System.identityHashCode(this));
-            } catch (Exception e) {
-                s_logger.error("Unable to unregister MBean", e);
-            }
+            s_logger.debug("Unregistering txn" + getId());
+	        s_mbean.removeTransaction(this);
         }
     }
     

utils/src/com/cloud/utils/db/TransactionMBean.java

@@ -20,12 +20,12 @@ package com.cloud.utils.db;
 import java.util.List;
 
 public interface TransactionMBean {
-    List<String> getStack();
+    int getTransactionCount();
     
-    String getName();
+    int getActiveTransactionCount();
     
-    String getDbConnection();
+    List<String> getTransactions();
+    
+    List<String> getActiveTransactions();
     
-    String getThreadName();
-
 }

utils/src/com/cloud/utils/db/TransactionMBeanImpl.java

@@ -17,52 +17,80 @@
  */
 package com.cloud.utils.db;
 
-import java.sql.Connection;
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
 
 import javax.management.StandardMBean;
 
 import com.cloud.utils.db.Transaction.StackElement;
 
 public class TransactionMBeanImpl extends StandardMBean implements TransactionMBean {
-    Transaction _txn = null;
-    String _threadName = null;
     
-    public TransactionMBeanImpl(Transaction txn) {
+    Map<Long, Transaction> _txns = new ConcurrentHashMap<Long, Transaction>();
+    
+    public TransactionMBeanImpl() {
         super(TransactionMBean.class, false);
-        _txn = txn;
-        _threadName = Thread.currentThread().getName();
+    }
+    
+    public void addTransaction(Transaction txn) {
+        _txns.put(txn.getId(), txn);
+    }
+    
+    public void removeTransaction(Transaction txn) {
+        _txns.remove(txn.getId());
     }
     
     @Override
-    public String getThreadName() {
-        return _threadName;
+    public int getTransactionCount() {
+        return _txns.size();
     }
     
     @Override
-    public List<String> getStack() {
-        ArrayList<StackElement> elements = new ArrayList<StackElement>(_txn.getStack());
-        ArrayList<String> stack = new ArrayList<String>(elements.size());
-        
-        for (StackElement element : elements) {
-            stack.add(element.toString());
+    public int getActiveTransactionCount() {
+        int count = 0;
+        for (Transaction txn : _txns.values()) {
+            if (txn.getStack().size() > 0) {
+                count++;
+            }
         }
-        
-        return stack;
+        return count;
     }
     
     @Override
-    public String getDbConnection() {
-        Connection conn = _txn.getCurrentConnection();
-        
-        return (conn != null) ? conn.toString() : "No DB connection";
+    public List<String> getTransactions() {
+        ArrayList<String> txns = new ArrayList<String>();
+        for (Transaction info : _txns.values()) {
+            txns.add(toString(info));
+        }
+        return txns;
     }
     
-
     @Override
-    public String getName() {
-        return _txn.getName();
+    public List<String> getActiveTransactions() {
+        ArrayList<String> txns = new ArrayList<String>();
+        for (Transaction txn : _txns.values()) {
+            if (txn.getStack().size() > 0 || txn.getCurrentConnection() != null) {
+                txns.add(toString(txn));
+            }
+        }
+        return txns;
     }
     
+    protected String toString(Transaction txn) {
+        StringBuilder buff = new StringBuilder("[Name=");
+        buff.append(txn.getName());
+        buff.append("; Creator=");
+        buff.append(txn.getCreator());
+        buff.append("; DB=");
+        buff.append(txn.getCurrentConnection());
+        buff.append("; Stack=");
+        for (StackElement element : txn.getStack()) {
+            buff.append(",").append(element.toString());
+        }
+        buff.append("]");
+        
+        return buff.toString();
+    }
 }