如何让Saxon XSLT处理器向stderr或log4j报告错误？

import net.sf.saxon.s9api.*;

public class XSLTProcessor {
    public static void main(String[] args) {
        try {
            Processor processor = new Processor(false);
            XsltCompiler compiler = processor.newXsltCompiler();
            XsltExecutable executable = compiler.compile(new StreamSource("input.xsl"));
            XsltTransformer transformer = executable.load();
            
            // 设置错误监听器，将错误信息输出到标准错误流
            transformer.setErrorListener(new StandardErrorListener());
            
            // 设置输入和输出
            transformer.setSource(new StreamSource("input.xml"));
            transformer.setDestination(new StreamResult("output.xml"));
            
            // 执行转换
            transformer.transform();
        } catch (SaxonApiException e) {
            e.printStackTrace();
        }
    }
}

class StandardErrorListener implements ErrorListener {
    @Override
    public void error(XdmNode node, QName qname, org.xml.sax.SAXParseException exception) throws XPathException {
        System.err.println("Error: " + exception.getMessage());
    }

    @Override
    public void fatalError(XdmNode node, QName qname, org.xml.sax.SAXParseException exception) throws XPathException {
        System.err.println("Fatal Error: " + exception.getMessage());
    }

    @Override
    public void warning(XdmNode node, QName qname, org.xml.sax.SAXParseException exception) throws XPathException {
        System.err.println("Warning: " + exception.getMessage());
    }
}

# 设置日志输出级别
log4j.rootLogger=ERROR, console

# 配置控制台输出
log4j.appender.console=org.apache.log4j.ConsoleAppender
log4j.appender.console.layout=org.apache.log4j.PatternLayout
log4j.appender.console.layout.ConversionPattern=%-4r [%t] %-5p %c %x - %m%n

import net.sf.saxon.s9api.*;

import org.apache.log4j.Logger;

public class XSLTProcessor {
    private static final Logger logger = Logger.getLogger(XSLTProcessor.class);

    public static void main(String[] args) {
        try {
            // 配置log4j
            PropertyConfigurator.configure("log4j.properties");

            Processor processor = new Processor(false);
            XsltCompiler compiler = processor.newXsltCompiler();
            XsltExecutable executable = compiler.compile(new StreamSource("input.xsl"));
            XsltTransformer transformer = executable.load();

            // 设置错误监听器，将错误信息记录到log4j日志
            transformer.setErrorListener(new Log4jErrorListener());

            // 设置输入和输出
            transformer.setSource(new StreamSource("input.xml"));
            transformer.setDestination(new StreamResult("output.xml"));

            // 执行转换
            transformer.transform();
        } catch (SaxonApiException e) {
            logger.error("Error: " + e.getMessage());
        }
    }
}

class Log4jErrorListener implements ErrorListener {
    private static final Logger logger = Logger.getLogger(Log4jErrorListener.class);

    @Override
    public void error(XdmNode node, QName qname, org.xml.sax.SAXParseException exception) throws XPathException {
        logger.error("Error: " + exception.getMessage());
    }

    @Override
    public void fatalError(XdmNode node, QName qname, org.xml.sax.SAXParseException exception) throws XPathException {
        logger.error("Fatal Error: " + exception.getMessage());
    }

    @Override
    public void warning(XdmNode node, QName qname, org.xml.sax.SAXParseException exception) throws XPathException {
        logger.warn("Warning: " + exception.getMessage());
    }
}