ch/qos/logback/core/status/StatusListener.java

ch/qos/logback/core/util/OptionHelper.java

ch/qos/logback/core/status/StatusManager.java

ch/qos/logback/core/status/StatusListener.java

ch/qos/logback/core/util/OptionHelper.java

org/springframework/boot/logging/logback/SpringBootJoranConfigurator.java

org/springframework/boot/logging/logback/defaults.xml

org/springframework/boot/logging/logback/defaults.xml

logback的FileAppender继承了OutputStreamAppender，它定义了append、prudent、bufferSize属性，它使用的是ResilientFileOutputStream，其writeOut方法主要是新增了对prudent模式的支持，在prudent为true时采用的是safe......

logback-core/src/main/java/ch/qos/logback/core/OutputStreamAppender.java