fix stackoverflow exception in testConnection

Author: nPraml

ebean-datasource/src/main/java/io/ebean/datasource/pool/ConnectionPool.java

@@ -369,10 +369,10 @@ private void heartBeat() {
   }
 
   private void testConnection() {
-    Connection conn = null;
+    PooledConnection conn = null;
     try {
       // Get a connection from the pool and test it
-      conn = getConnection();
+      conn = getPooledConnection();
       heartbeatPoolExhaustedCount = 0;
       if (testConnection(conn)) {
         notifyDataSourceIsUp();
@@ -394,7 +394,7 @@ private void testConnection() {
           if (!conn.getAutoCommit()) {
             conn.rollback();
           }
-          conn.close();
+          conn.closePooledConnection(false);
         }
       } catch (SQLException ex) {
         Log.warn("Can't close connection in checkDataSource!");
@@ -541,8 +541,12 @@ void returnConnection(PooledConnection pooledConnection) {
   /**
    * This is a bad connection and must be removed from the pool's busy list and fully closed.
    */
-  void returnConnectionForceClose(PooledConnection pooledConnection) {
+  void returnConnectionForceClose(PooledConnection pooledConnection, boolean testPool) {
     returnTheConnection(pooledConnection, true);
+    if (testPool) {
+      // Got a bad connection so check the pool
+      testConnection();
+    }
   }
 
   void removeClosedConnection(PooledConnection pooledConnection) {
@@ -558,10 +562,6 @@ private void returnTheConnection(PooledConnection pooledConnection, boolean forc
       poolListener.onBeforeReturnConnection(pooledConnection);
     }
     queue.returnPooledConnection(pooledConnection, forceClose);
-    if (forceClose) {
-      // Got a bad connection so check the pool
-      testConnection();
-    }
   }
 
   void returnConnectionReset(PooledConnection pooledConnection) {

ebean-datasource/src/main/java/io/ebean/datasource/pool/PooledConnection.java

@@ -445,12 +445,16 @@ private boolean isReadOnlyMessage(SQLException ex) {
    */
   @Override
   public void close() throws SQLException {
+    closePooledConnection(true);
+  }
+
+  void closePooledConnection(boolean testPool) throws SQLException {
     if (status == STATUS_IDLE) {
       throw new SQLException(IDLE_CONNECTION_ACCESSED_ERROR + "close()");
     }
     boolean mayHaveUncommittedChanges = !autoCommit && !readOnly && status == STATUS_ACTIVE;
     if (mayHaveUncommittedChanges && pool.enforceCleanClose()) {
-      pool.returnConnectionForceClose(this);
+      pool.returnConnectionForceClose(this, testPool);
       throw new AssertionError("Tried to close a dirty connection. See https://github.com/ebean-orm/ebean-datasource/issues/116 for details.");
     }
     if (hadErrors) {
@@ -459,7 +463,7 @@ public void close() throws SQLException {
         return;
       } else if (pool.invalidConnection(this)) {
         // the connection is BAD, remove it, close it and test the pool
-        pool.returnConnectionForceClose(this);
+        pool.returnConnectionForceClose(this, testPool);
         return;
       }
     }
@@ -513,7 +517,7 @@ public void close() throws SQLException {
     } catch (Exception ex) {
       // the connection is BAD, remove it, close it and test the pool
       Log.warn("Error when trying to return connection to pool, closing fully.", ex);
-      pool.returnConnectionForceClose(this);
+      pool.returnConnectionForceClose(this, testPool);
     }
   }