core/src/main/java/com/orientechnologies/orient/core/db/ODatabasePoolBase.java
public int getAvailableConnections(final String name, final String userName) {
    setup();
    return dbPool.getAvailableConnections(name, userName);
  }
public int getAvailableConnections(final String name, final String userName) {
    setup();
    return dbPool.getAvailableConnections(name, userName);
  }
Returns amount of available connections which you can acquire for given source and user name. Source id is consist of
"source name" and "source user name".

@param name
Source name.
@param userName
User name which is used to acquire source.
@return amount of available connections which you can acquire for given source and user name.