webapp中的derby.log(etc)控件

Derby有一系列由系统属性控制的配置选项。在webapp中安排系统属性设置是非常痛苦的。有人想出解决办法了吗?

下面是servlet上下文侦听器的代码。仍然在容器的cwd中创建derby.log,而不是调用我的日志过程。

/**
 * Listener to try to get Derby to behave better.
 */
public class ContextListener implements ServletContextListener {

    private static final String TEMP_DIR_ATTRIBUTE = "javax.servlet.context.tempdir";
    private static ServletContext context;
    private static Writer logWriter;

    private class LogWriter extends Writer {

        @Override
        public void close() throws IOException {
        }

        @Override
        public void flush() throws IOException {
        }

        @Override
        public void write(char[] cbuf, int off, int len) throws IOException {
            context.log(new String(cbuf, off, len));
        }

    }

    /** {@inheritDoc}*/
    public void contextDestroyed(ServletContextEvent sce) {
    }

    public static Writer getLogSteam() {
        return logWriter;
    }

    /** {@inheritDoc}*/
    public void contextInitialized(ServletContextEvent sce) {
        logWriter = new LogWriter();
        File tempDirFile = (File)sce.getServletContext().getAttribute(TEMP_DIR_ATTRIBUTE);
        context = sce.getServletContext();
        System.setProperty("derby.system.home", tempDirFile.getAbsolutePath());
        System.setProperty("derby.stream.error.method", "com.basistech.vws.ContextListener.getLogStream");
    }

}