如何让java日志输出显示在一行上?

问题

目前,默认条目如下所示:

Oct 12, 2008 9:45:18 AM myClassInfoHere
INFO: MyLogMessageHere

我怎么做到这一点?

Oct 12, 2008 9:45:18 AM myClassInfoHere - INFO: MyLogMessageHere

澄清我正在使用java.util.logging


#1 热门回答(71 赞)

从Java 7,java.util.logging.SimpleFormatter开始,支持从系统属性获取其format,因此将这样的内容添加到JVM命令行将导致它在一行上打印:

-Djava.util.logging.SimpleFormatter.format='%1$tY-%1$tm-%1$td %1$tH:%1$tM:%1$tS %4$s %2$s %5$s%6$s%n'

或者,你也可以将此添加到你的logger.properties

java.util.logging.SimpleFormatter.format='%1$tY-%1$tm-%1$td %1$tH:%1$tM:%1$tS %4$s %2$s %5$s%6$s%n'

#2 热门回答(67 赞)

1)-Djava.util.logging.SimpleFormatter.format

Java 7支持具有java.util.Formatter格式字符串语法的属性。

-Djava.util.logging.SimpleFormatter.format=...

Seehere

我最喜欢的是:

-Djava.util.logging.SimpleFormatter.format=%1$tY-%1$tm-%1$td %1$tH:%1$tM:%1$tS %4$-6s %2$s %5$s%6$s%n

这使输出像:

2014-09-02 16:44:57 SEVERE org.jboss.windup.util.ZipUtil unzip: Failed to load: foo.zip

2)将它放到IDE中

IDE通常允许你为项目设置系统属性。例如。在NetBeans中,而不是在某处添加-D ... = ...,在动作对话框中添加属性,形式为java.util.logging.SimpleFormatter.format=%1$tY-%1$tm-...-没有任何引号。 IDE应该弄清楚。

3)把它放到Maven - Surefire

为了你的方便,以下是如何将它放到Surefire:

<!-- Surefire -->
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-surefire-plugin</artifactId>
            <version>2.17</version>
            <configuration>
                <systemPropertyVariables>
                    <!-- Set JUL Formatting -->
                    <java.util.logging.SimpleFormatter.format>%1$tY-%1$tm-%1$td %1$tH:%1$tM:%1$tS %4$-6s %2$s %5$s%6$s%n</java.util.logging.SimpleFormatter.format>
                </systemPropertyVariables>
            </configuration>
        </plugin>

4)手工制作

我有一个图书馆withfewjava.util.logging相关课程。其中,它是SingleLineFormatter。可下载的jarhere

public class SingleLineFormatter extends Formatter {

  Date dat = new Date();
  private final static String format = "{0,date} {0,time}";
  private MessageFormat formatter;
  private Object args[] = new Object[1];

  // Line separator string.  This is the value of the line.separator
  // property at the moment that the SimpleFormatter was created.
  //private String lineSeparator = (String) java.security.AccessController.doPrivileged(
  //        new sun.security.action.GetPropertyAction("line.separator"));
  private String lineSeparator = "\n";

  /**
   * Format the given LogRecord.
   * @param record the log record to be formatted.
   * @return a formatted log record
   */
  public synchronized String format(LogRecord record) {

    StringBuilder sb = new StringBuilder();

    // Minimize memory allocations here.
    dat.setTime(record.getMillis());    
    args[0] = dat;


    // Date and time 
    StringBuffer text = new StringBuffer();
    if (formatter == null) {
      formatter = new MessageFormat(format);
    }
    formatter.format(args, text, null);
    sb.append(text);
    sb.append(" ");


    // Class name 
    if (record.getSourceClassName() != null) {
      sb.append(record.getSourceClassName());
    } else {
      sb.append(record.getLoggerName());
    }

    // Method name 
    if (record.getSourceMethodName() != null) {
      sb.append(" ");
      sb.append(record.getSourceMethodName());
    }
    sb.append(" - "); // lineSeparator



    String message = formatMessage(record);

    // Level
    sb.append(record.getLevel().getLocalizedName());
    sb.append(": ");

    // Indent - the more serious, the more indented.
    //sb.append( String.format("% ""s") );
    int iOffset = (1000 - record.getLevel().intValue()) / 100;
    for( int i = 0; i < iOffset;  i++ ){
      sb.append(" ");
    }


    sb.append(message);
    sb.append(lineSeparator);
    if (record.getThrown() != null) {
      try {
        StringWriter sw = new StringWriter();
        PrintWriter pw = new PrintWriter(sw);
        record.getThrown().printStackTrace(pw);
        pw.close();
        sb.append(sw.toString());
      } catch (Exception ex) {
      }
    }
    return sb.toString();
  }
}

#3 热门回答(38 赞)

与Tervor类似,但我喜欢在运行时更改属性。

请注意,这需要在创建第一个SimpleFormatter之前设置 - 正如在注释中所写的那样。

System.setProperty("java.util.logging.SimpleFormatter.format", 
            "%1$tF %1$tT %4$s %2$s %5$s%6$s%n");