我在 JBoss AS 7.1.1.Final 上部署的 Spring 3.1.1.RELEASE 应用程序中使用 log4j 1.2.15。我正在尝试将 log4j 中写入的输出路由到我的响应输出流。我的输出是这样写的
private static final Logger LOG = Logger.getLogger(TrainingSessionServiceImpl.class);
…
LOG.info("Creating/updating training session associated with order #:" + order.getId());
我正在尝试将其路由到我的输出流,就像这样......
@RequestMapping(value = "/refreshPd", method = RequestMethod.GET)
public void refreshPD(final HttpServletResponse response) throws IOException
{
...
final WriterAppender appender = new WriterAppender(new PatternLayout("%d{ISO8601} %p - %m%n"),response.getWriter());
appender.setName("CONSOLE_APPENDER");
appender.setThreshold(org.apache.log4j.Level.DEBUG);
Logger.getRootLogger().addAppender(appender);
worker.work();
Logger.getRootLogger().removeAppender("CONSOLE_APPENDER");
但遗憾的是,即使我知道(通过调试)正在调用日志记录语句,我的浏览器也没有任何输出。有谁知道我如何调整我的设置以使其正常工作?下面是我的 log4j.properties 文件,部署到我的 war 的 WEB-INF/classes 目录。
log4j.rootLogger=DEBUG, CA, FA
#Console Appender
log4j.appender.CA=org.apache.log4j.ConsoleAppender
log4j.appender.CA.layout=org.apache.log4j.PatternLayout
log4j.appender.CA.layout.ConversionPattern=%-4r [%t] %-5p %c %x - %m%n
#File Appender
log4j.appender.FA=org.apache.log4j.FileAppender
log4j.appender.FA.File=/usr/java/jboss/server/default/log/log4j.log
log4j.appender.FA.layout=org.apache.log4j.PatternLayout
log4j.appender.FA.layout.ConversionPattern=%-4r [%t] %-5p %c %x - %m%n
# Set the logger level of File Appender to WARN
log4j.appender.FA.Threshold = DEBUG
谢谢,-戴夫
最佳答案
这是一个有趣的问题。 关键是编写自己的附加程序。我查找了内置的 org.apache.log4j.ConsoleAppender 代码以获取灵感。我已经在我的 tomcat 中对此进行了测试并验证了它的工作原理。我使用了 log4j-1.2.17 (希望不重要)
1) 首先实现你自己的appender。此附加程序会将所有日志事件写入当前线程的输出流
package com.tstwbprj.log;
import org.apache.log4j.Layout;
import org.apache.log4j.WriterAppender;
import java.io.IOException;
import java.io.OutputStream;
public class HttpLogAppender extends WriterAppender {
static ThreadLocal<OutputStream> streamPerHttpThread = new ThreadLocal<OutputStream>();
public HttpLogAppender() {
}
public HttpLogAppender(Layout layout) {
setLayout(layout); //super-class method
activateOptions();
}
public void setCurrentHttpStream(OutputStream stream) {
streamPerHttpThread.set(stream);
}
public void activateOptions() {
setWriter(createWriter(new CurrentHttpThreadOutStream()));
}
/**
* An implementation of OutputStream that redirects to the
* current http threads servlet output stream
*/
private static class CurrentHttpThreadOutStream extends OutputStream {
public CurrentHttpThreadOutStream() {
}
public void close() {
}
public void flush() throws IOException {
OutputStream stream = streamPerHttpThread.get();
if (stream != null) {
stream.flush();
}
}
public void write(final byte[] b) throws IOException {
OutputStream stream = streamPerHttpThread.get();
if (stream != null) {
stream.write(b);
}
}
public void write(final byte[] b, final int off, final int len)
throws IOException {
OutputStream stream = streamPerHttpThread.get();
if (stream != null) {
stream.write(b, off, len);
}
}
public void write(final int b) throws IOException {
OutputStream stream = streamPerHttpThread.get();
if (stream != null) {
stream.write(b);
}
}
}
}
2)像其他设置一样将此附加程序添加到您的 log4j 配置文件中
log4j.rootLogger=DEBUG, CA, FA , HA
..
log4j.appender.HA=com.tstwbprj.log.HttpLogAppender log4j.appender.HA.layout=org.apache.log4j.PatternLayout log4j.appender.HA.layout.ConversionPattern=%-4r [%t] %-5p %c %x - %m%n
3) 在您的 servlet 中添加一小段代码,以便此附加程序正常工作。这是我的 servlet。
import org.apache.log4j.Category;
import org.apache.log4j.Logger;
import javax.servlet.ServletOutputStream;
import java.io.IOException;
public class LogServlet extends javax.servlet.http.HttpServlet {
private static final Logger LOG = Logger.getLogger(LogServlet.class);
protected void doPost(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response) throws javax.servlet.ServletException, IOException {
}
protected void doGet(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response) throws javax.servlet.ServletException, IOException {
ServletOutputStream outstream = response.getOutputStream();
configureLogForCurrentRequest(outstream);
LOG.info("Got request");//this is now send to the servlet output stream !!
LOG.info("Hello!!");
LOG.info("Done!!");
}
private void configureLogForCurrentRequest(ServletOutputStream outstream) {
HttpLogAppender appender = (HttpLogAppender) LOG.getAppender("HA");
while (appender == null) {
Category parent = LOG.getParent();
if (parent == null) {
break; //This ideally shouldn't happen. Navigated all the way to root logger and still did not find appender !!..something wrong with log4j configuration setup
}
appender = (HttpLogAppender) parent.getAppender("HA");
}
appender.setCurrentHttpStream(outstream);
}
}
警告:这没有经过彻底的测试,特别是对于多个 servlet 请求等。也不确定为什么要这样做。将日志消息通过管道传输到浏览器并不常见。谨慎行事..:)-
关于spring - 如何将 log4j 输出重定向到 HttpServletResponse 输出流?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/14408822/