Logback Pattern

Logback日志配置示例

<appender name="SYSLOG" class="ch.qos.logback.classic.net.SyslogAppender">
        <syslogHost>10.177.81.90</syslogHost>
        <facility>local0</facility>
        <port>514</port>
        <suffixPattern>%date %-5level [%thread] %logger{43}\(%L\) : %msg</suffixPattern>
</appender>
<appender name="EMAIL" class="ch.qos.logback.classic.net.SMTPAppender">
        <filter class="ch.qos.logback.classic.filter.ThresholdFilter">
            <level>ERROR</level>
        </filter>
        <smtpHost>${MAIL_HOST}</smtpHost>
        <smtpPort>${MAIL_PORT}}</smtpPort>
        <SSL>true</SSL>
        <username>${MAIL_USERNAME}</username>
        <password>${MAIL_PASSWORD}</password>
        <from>${MAIL_FROM}</from>
        <to>${MAIL_TO}</to>
        <subject>平台日志报警 [${HOSTNAME}]</subject>
        <layout class="ch.qos.logback.classic.PatternLayout">
            <pattern>%date %-5level %logger{0} - %message%n</pattern>
        </layout>
        <cyclicBufferTracker class="ch.qos.logback.core.spi.CyclicBufferTracker">
            <!-- send just one log entry per email -->
            <bufferSize>10</bufferSize>
        </cyclicBufferTracker>
    </appender>

其中SYSLOG的suffixPattern，%date %-5level [%thread] %logger{43}\(%L\) : %msg， 和EMAIL的layout pattern，%date %-5level %logger{0} - %message%n，就是配置日志的格式。

Pattern关键字

Conversion Word	Effect
c{length} lo{length} logger{length}	Outputs the name of the logger at the origin of the logging event.This conversion word takes an integer as its first and only option. The converter's abbreviation algorithm will shorten the logger name, usually without significant loss of meaning. Setting the value of length option to zero constitutes an exception. It will cause the conversion word to return the sub-string right to the rightmost dot character in the logger name. The next table provides examples of the abbreviation algorithm in action.Conversion specifierLogger nameResult%loggermainPackage.sub.sample.BarmainPackage.sub.sample.Bar%logger{0}mainPackage.sub.sample.BarBar%logger{5}mainPackage.sub.sample.Barm.s.s.Bar%logger{10}mainPackage.sub.sample.Barm.s.s.Bar%logger{15}mainPackage.sub.sample.Barm.s.sample.Bar%logger{16}mainPackage.sub.sample.Barm.sub.sample.Bar%logger{26}mainPackage.sub.sample.BarmainPackage.sub.sample.BarPlease note that the rightmost segment in a logger name is never abbreviated, even if its length is longer than the length option. Other segments may be shortened to at most a single character but are never removed.
C{length} class{length}	Outputs the fully-qualified class name of the caller issuing the logging request.Just like the %logger conversion word above, this conversion takes an integer as an option to shorten the class name. Zero carries special meaning and will cause the simple class name to be printed without the package name prefix. By default the class name is printed in full.Generating the caller class information is not particularly fast. Thus, its use should be avoided unless execution speed is not an issue.
contextName****cn	Outputs the name of the logger context to which the logger at the origin of the event was attached to.
d{pattern} date{pattern} d{pattern, timezone} date{pattern, timezone}	Used to output the date of the logging event. The date conversion word admits a pattern string as a parameter. The pattern syntax is compatible with the format accepted by java.text.SimpleDateFormat.You can specify the string "ISO8601" for the ISO8601 date format. Note that the %date conversion word defaults to the ISO 8601 date format in the absence of a pattern parameter.Here are some sample parameter values. They assume that the actual date is Friday 20th of October, 2006 and that the author has returned to working on this document just after lunch.Conversion PatternResult%d2006-10-20 14:06:49,812%date2006-10-20 14:06:49,812%date{ISO8601}2006-10-20 14:06:49,812%date{HH:mm:ss.SSS}14:06:49.812%date{dd MMM yyyy;HH:mm:ss.SSS}20 oct. 2006;14:06:49.812The second parameter specifies a timezone. For example, the '%date{HH:mm:ss.SSS, Australia/Perth} would print the time in the time zone of Perth, Australia, the world's most isolated city. Note that in the absence of the timezone parameter, the default timezone of the host Java platform is used. If the specified timezone identifier is unknown or misspelled, the GMT timezone is assumed as dictated by the TimeZone.getTimeZone(String) method specification.COMMON ERROR Given that the comma ',' character is interpreted as the parameter separator, the pattern HH:mm:ss,SSS will be interpreted as the pattern HM:mm:ss and the timezone SSS. If you wish to include a comma in your date pattern, then simply enclose the pattern between quotes. For example, %date{"HH:mm:ss,SSS"}.
F / file	Outputs the file name of the Java source file where the logging request was issued.Generating the file information is not particularly fast. Thus, its use should be avoided unless execution speed is not an issue.
caller{depth}caller{depthStart..depthEnd}caller{depth, evaluator-1, ... evaluator-n}****caller{depthStart..depthEnd, evaluator-1, ... evaluator-n}	Outputs location information of the caller which generated the logging event.The location information depends on the JVM implementation but usually consists of the fully qualified name of the calling method followed by the caller's source, the file name and line number between parentheses.A integer can be added to the caller conversion specifier's options to configure the depth of the information to be displayed.For example, %caller{2} would display the following excerpt:0 [main] DEBUG - logging statement Caller+0 at mainPackage.sub.sample.Bar.sampleMethodName(Bar.java:22)Caller+1 at mainPackage.sub.sample.Bar.createLoggingRequest(Bar.java:17)And %caller{3} would display this other excerpt:16 [main] DEBUG - logging statement Caller+0 at mainPackage.sub.sample.Bar.sampleMethodName(Bar.java:22)Caller+1 at mainPackage.sub.sample.Bar.createLoggingRequest(Bar.java:17)Caller+2 at mainPackage.ConfigTester.main(ConfigTester.java:38)A range specifier can be added to the caller conversion specifier's options to configure the depth range of the information to be displayed.For example, %caller{1..2} would display the following excerpt:0 [main] DEBUG - logging statementCaller+0 at mainPackage.sub.sample.Bar.createLoggingRequest(Bar.java:17)This conversion word can also use evaluators to test logging events against a given criterion before computing caller data. For example, using %caller{3, CALLER_DISPLAY_EVAL} will display three lines of stacktrace, only if the evaluator called CALLER_DISPLAY_EVAL returns a positive answer.Evaluators are described below.
L / line	Outputs the line number from where the logging request was issued.Generating the line number information is not particularly fast. Thus, its use should be avoided unless execution speed is not an issue.
m / msg / message	Outputs the application-supplied message associated with the logging event.
M / method	Outputs the method name where the logging request was issued.Generating the method name is not particularly fast. Thus, its use should be avoided unless execution speed is not an issue.
n	Outputs the platform dependent line separator character or characters.This conversion word offers practically the same performance as using non-portable line separator strings such as "\n", or "\r\n". Thus, it is the preferred way of specifying a line separator.
p / le / level	Outputs the level of the logging event.
r / relative	Outputs the number of milliseconds elapsed since the start of the application until the creation of the logging event.
t / thread	Outputs the name of the thread that generated the logging event.
X{key:-defaultVal} mdc{key:-defaultVal}	Outputs the MDC (mapped diagnostic context) associated with the thread that generated the logging event.If the mdc conversion word is followed by a key between braces, as in %mdc{userid}, then the MDC value corresponding to the key 'userid' will be output. If the value is null, then the default value specified after the :- operator is output. If no default value is specified than the empty string is output.If no key is given, then the entire content of the MDC will be output in the format "key1=val1, key2=val2".See the chapter on MDC for more details on the subject.
ex{depth} exception{depth} throwable{depth} ex{depth, evaluator-1, ..., evaluator-n} exception{depth, evaluator-1, ..., evaluator-n} throwable{depth, evaluator-1, ..., evaluator-n}	Outputs the stack trace of the exception associated with the logging event, if any. By default the full stack trace will be output.The throwable conversion word can followed by one of the following options:short: prints the first line of the stack tracefull: prints the full stack traceAny integer: prints the given number of lines of the stack traceHere are some examples:Conversion PatternResult%exmainPackage.foo.bar.TestException: Houston we have a problem at mainPackage.foo.bar.TestThrower.fire(TestThrower.java:22) at mainPackage.foo.bar.TestThrower.readyToLaunch(TestThrower.java:17) at mainPackage.ExceptionLauncher.main(ExceptionLauncher.java:38)%ex{short}mainPackage.foo.bar.TestException: Houston we have a problem at mainPackage.foo.bar.TestThrower.fire(TestThrower.java:22)%ex{full}mainPackage.foo.bar.TestException: Houston we have a problem at mainPackage.foo.bar.TestThrower.fire(TestThrower.java:22) at mainPackage.foo.bar.TestThrower.readyToLaunch(TestThrower.java:17) at mainPackage.ExceptionLauncher.main(ExceptionLauncher.java:38)%ex{2}mainPackage.foo.bar.TestException: Houston we have a problem at mainPackage.foo.bar.TestThrower.fire(TestThrower.java:22) at mainPackage.foo.bar.TestThrower.readyToLaunch(TestThrower.java:17)This conversion word can also use evaluators to test logging events against a given criterion before creating the output. For example, using %ex{full, EX_DISPLAY_EVAL} will display the full stack trace of the exception only if the evaluator called EX_DISPLAY_EVALreturns a negative answer. Evaluators are described further down in this document.If you do not specify %throwable or another throwable-related conversion word in the conversion pattern, PatternLayout will automatically add it as the last conversion word, on account of the importance of stack trace information. The $nopex conversion word can be substituted for %throwable, if you do not wish stack trace information to be displayed. See also the %nopex conversion word.
xEx{depth} xException{depth} xThrowable{depth} xEx{depth, evaluator-1, ..., evaluator-n} xException{depth, evaluator-1, ..., evaluator-n} xThrowable{depth, evaluator-1, ..., evaluator-n}	Same as the %throwable conversion word above with the addition of class packaging information.At the end of each stack frame of the exception, a string consisting of the jar file containing the relevant class followed by the "Implementation-Version" as found in that jar's manifest will be added. This innovative technique was originally suggested by James Strachan. If the information is uncertain, then the class packaging data will be preceded by a tilde, i.e. the '~' character.Here is an example:java.lang.NullPointerException at com.xyz.Wombat(Wombat.java:57) ~[wombat-1.3.jar:1.3] at com.xyz.Wombat(Wombat.java:76) ~[wombat-1.3.jar:1.3] at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.5.0_06] at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) ~[na:1.5.0_06] at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) ~[na:1.5.0_06] at java.lang.reflect.Method.invoke(Method.java:585) ~[na:1.5.0_06] at org.junit.internal.runners.TestMethod.invoke(TestMethod.java:59) [junit-4.4.jar:na] at org.junit.internal.runners.MethodRoadie.runTestMethod(MethodRoadie.java:98) [junit-4.4.jar:na] ...etc Logback goes to great lengths to ensure that the class packaging information it displays is correct, even in arbitrarily complex class loader hierarchies. However, when it is unable to guarantee the absolute correctness of the information, then it will prefix the data with a tilde, i.e. the '~' character. Thus, it is theoretically possible for the printed class packaging information to differ from the real class packaging information. So, in the above example, given that packaging data for the Wombat class is preceded by a tilde, it is possible that the correct packaging data is in reality [wombat.jar:1.7].Please note that given its potential cost, computation of packaging data is disabled by default. When computation of packaging data is enabled, PatternLayout will automatically assume the %xThrowable suffix instead of %throwable suffix at the end of the pattern string.Feedback from users indicates that Netbeans chokes on packaging information.
nopex nopexception	Although it pretends to handle stack trace data, this conversion word does not output any data, thus, effectively ignoring exceptions.The %nopex conversion word allows the user to override PatternLayout's internal safety mechanism which silently adds the %xThrowable conversion keyword in the absence of another conversion word handling exceptions.
marker	Outputs the marker associated with the logger request.In case the marker contains children markers, the converter displays the parent as well as childrens' names according to the format shown below.parentName [ child1, child2 ]
property{key}	Outputs the value associated with a property named key. The the relevant docs on how to define ion entitled define variables and variable scopes. If key is not a property of the logger context, then key will be looked up in the System properties.There is no default value for key. If it is omitted, the returned value will be "Property_HAS_NO_KEY", expliciting the error condition.
replace(p){r, t}	Replaces occurrences of 'r', a regex, with its replacement 't' in the string produces by the sub-pattern 'p'. For example, "%replace(%msg){'\s', ''}" will remove all spaces contained in the event message.The pattern 'p' can be arbitrarily complex and in particular can contain multiple conversion keywords. For instance, "%replace(%logger %msg){'.', '/'}" will replace all dots in the logger or the message of the event with a forward slash.
rEx{depth} rootException{depth} rEx{depth, evaluator-1, ..., evaluator-n} rootException{depth, evaluator-1, ..., evaluator-n}	Outputs the stack trace of the exception associated with the logging event, if any. The root cause will be output first instead of the standard "root cause last". Here is a sample output (edited for space):java.lang.NullPointerException at com.xyz.Wombat(Wombat.java:57) ~[wombat-1.3.jar:1.3] at com.xyz.Wombat(Wombat.java:76) ~[wombat-1.3.jar:1.3]Wrapped by: org.springframework.BeanCreationException: Error creating bean with name 'wombat': at org.springframework.AbstractBeanFactory.getBean(AbstractBeanFactory.java:248) [spring-2.0.jar:2.0] at org.springframework.AbstractBeanFactory.getBean(AbstractBeanFactory.java:170) [spring-2.0.jar:2.0] at org.apache.catalina.StandardContext.listenerStart(StandardContext.java:3934) [tomcat-6.0.26.jar:6.0.26]The %rootException converter admits the same optional parameters as the %xException converter described above, including depth and evaluators. It outputs also packaging information. In short, %rootException is very similar to %xException, only the order of exception output is reversed.Tomasz Nurkiewicz, the author of %rootException converter, documents his contribution in a blog entry entitled "Logging exceptions root cause first".

使用注意项

在pattern中括号"()"有特殊含义，如：%-30(%d{HH:mm:ss.SSS} [%thread]) %-5level %logger{32} - %msg%n，可以用来表示一个group，然后对这个group设定格式，所以要使用括号的时候需要用反斜杠转义，如：%date %-5level [%thread] %logger{43}\(%L\) : %msg。

格式设定

格式说明

Format modifier	Left justify	Minimum width	Maximum width	Comment
%20logger	false	20	none	Left pad with spaces if the logger name is less than 20 characters long.
%-20logger	true	20	none	Right pad with spaces if the logger name is less than 20 characters long.
%.30logger	NA	none	30	Truncate from the beginning if the logger name is longer than 30 characters.
%20.30logger	false	20	30	Left pad with spaces if the logger name is shorter than 20 characters. However, if logger name is longer than 30 characters, then truncate from the beginning.
%-20.30logger	true	20	30	Right pad with spaces if the logger name is shorter than 20 characters. However, if logger name is longer than 30 characters, then truncate from the beginning.
%.-30logger	NA	none	30	Truncate from the end if the logger name is longer than 30 characters.

示例

Format modifier	Logger name	Result
[%20.20logger]	main.Name	[ main.Name]
[%-20.20logger]	main.Name	[main.Name ]
[%10.10logger]	main.foo.foo.bar.Name	[o.bar.Name]
[%10.-10logger]	main.foo.foo.bar.Name	[main.foo.f]

更多

Logback日志颜色设置等更多特性请参考logback layout。

参考

Logback PatternLayout