When closing database resources it is possible to get multiple exceptions and it is important not to lose any of them.

All of the tutorials that I have read only show the use of printStackTrace() during exception handling. However, that approach is not sophisticated enough for Enterprise applications. I use the following technique: Exceptions (and Errors if applicable) are held in an ArrayList until all resources are closed. Then the list is examined. If exceptions are present, they are processed as needed.

    // This code is part of my DataAccess class. Other code in the class is responsible for
    // opening the database connection and creating a prepared statement - both are
    // static objects.

    public synchronized static void free() {
        // This list holds any exception objects that are caught.
        List caughtExceptions = new ArrayList();

        if (ps != null) {
            try {
                ps.close();
                logger.debug("free; closed prepared statement.");
            } catch (SQLException e) {
                caughtExceptions.add(e);
            }
        }
        if (con != null) {
            try {
                con.close();
	    	logger.debuf("free; closed database connection.");
            } catch (SQLException e) {
                caughtExceptions.add(e);
            }
        }

        if (caughtExceptions.size() > 0) {
            LogConfiguration.message(caughtExceptions, "Problem closing database resources.");
        }
    }

    // Here is the LogConfiguration.message() method which resides in a different class
    // from the above code.

	public static void message(final List exceptions, final String message) {
	    logger.fatal(message);
	    int throwableIndex = 1;
	    int throwableCount = exceptions.size();
	    for (Iterator iter = exceptions.iterator(); iter.hasNext(); ) {
	        Throwable t = (Throwable) iter.next();
		    logger.fatal("Exception [" + throwableIndex + "] of [" + throwableCount + "]", t);
		    throwableIndex++;
	    }
	}