使用filebeat5.0.1版本，用filebeat作爲日誌收集工具時：
java日誌格式需要多行匹配，在filebeat配置文件中添加：
### Multiline options
# Mutiline can be used for log messages spanning multiple lines. This is common
# for Java Stack Traces or C-Line Continuation
# The regexp Pattern that has to be matched. The example pattern matches all lines starting with [
multiline.pattern: ^\[
# Defines if the pattern set under pattern should be negated or not. Default is false.
multiline.negate: true
# Match can be set to "after" or "before". It is used to define if lines should be append to a pattern
# that was (not) matched before or after or as long as a pattern is not matched based on negate.
# Note: After is the equivalent to previous and before is the equivalent to to next in Logstash
multiline.match: after
上面配置的意思是：不以[開頭的行都合併到上一行的末尾
pattern：正則表達式
negate：true 或 false；默認是false，匹配pattern的行合併到上一行；true，不匹配pattern的行合併到上一行
match：after 或 before，合併到上一行的末尾或開頭