在spring中使用logging.config=logback-spring.xml将日志转存到了文件中。但是代码中的捕获的异常无法用 e.printStackTrace 打印到文件中。使用如下方法打印:
main: catch(Exception e){ log.error("xxx",e); }
这里可以重新定向 system.out 和err的输出,到logback:
https://stackoverflow.com/questions/1200175/log4j-redirect-stdout-to-dailyrollingfileappender
用于捕获运行时异常。
package com.italktv.platform.audioDist; import java.io.IOException; import java.io.OutputStream; import java.io.PrintStream; import org.apache.log4j.Level; import org.apache.log4j.Logger; public class Log4jStdOutErrProxy { public static void bind() { bind(Logger.getLogger("STDOUT"), Logger.getLogger("STDERR")); } @SuppressWarnings("resource") public static void bind(Logger loggerOut, Logger loggerErr) { // System.setOut(new PrintStream(new LoggerStream(loggerOut, Level.INFO, System.out), true)); System.setErr(new PrintStream(new LoggerStream(loggerErr, Level.ERROR, System.err), true)); } private static class LoggerStream extends OutputStream { private final Logger logger; private final Level logLevel; private final OutputStream outputStream; private StringBuilder sbBuffer; public LoggerStream(Logger logger, Level logLevel, OutputStream outputStream) { this.logger = logger; this.logLevel = logLevel; this.outputStream = outputStream; sbBuffer = new StringBuilder(); } @Override public void write(byte[] b) throws IOException { doWrite(new String(b)); } @Override public void write(byte[] b, int off, int len) throws IOException { doWrite(new String(b, off, len)); } @Override public void write(int b) throws IOException { doWrite(String.valueOf((char) b)); } private void doWrite(String str) throws IOException { sbBuffer.append(str); if (sbBuffer.charAt(sbBuffer.length() - 1) == ' ') { // The output is ready sbBuffer.setLength(sbBuffer.length() - 1); // remove ' ' if (sbBuffer.charAt(sbBuffer.length() - 1) == ' ') { sbBuffer.setLength(sbBuffer.length() - 1); // remove ' ' } String buf = sbBuffer.toString(); sbBuffer.setLength(0); outputStream.write(buf.getBytes()); outputStream.write(' '); logger.log(logLevel, buf); } } } // inner class LoggerStream }
初始化时调用:
// initialize logging to go to rolling log file
LogManager.resetConfiguration();
// and output on the original stdout
System.out.println("Hello on old stdout");
Log4jStdOutErrProxy.bind();