Rolling log Files & removing old log files

Question

I am working on a Java SOAP based webservice application where I am writing stdout to a text file as log for our reference. That file is growing enormously, so I need to check for the size of the file... For example if the file size crosses 10 Mb, I have to create another file.

Like this, I have to create 10 files, rotating one after the other until ten files. After reaching ten files, I have to delete the starting files and start creating again...

How can I delete files after the no. of files will become 10?

Answer 1

I use logback to do this. The example below is a time based rolling policy. Depending upon how much data your outputting during your logs, this may work for you as-is.

Also, as a bonus, my config file tosses the log into HTML to make it easy to view for management types who want to look though the log file.

Relevant part of the config file:

 <appender name="FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">     <file>logs\logFile.html</file>     <rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">         <!-- daily rollover -- >         <fileNamePattern>logs\logFile.%d{yyyy-MM-dd}.%i.html</fileNamePattern>         <timeBasedFileNamingAndTriggeringPolicy             class="ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP">             <!-- or whenever the file size reaches 10MB -- >             <maxFileSize>10MB</maxFileSize>         </timeBasedFileNamingAndTriggeringPolicy>         <!-- keep 10 days worth of history -->         <maxHistory>10</maxHistory>     </rollingPolicy>      <encoder class="ch.qos.logback.core.encoder.LayoutWrappingEncoder">         <charset>UTF-8</charset>         <layout class="ch.qos.logback.classic.html.HTMLLayout">             <pattern>%d{HH:mm:ss.SSS}%thread%level%logger%line%msg</pattern>         </layout>                </encoder> </appender>   <root level="DEBUG">     <appender-ref ref="STDOUT" />     <appender-ref ref="FILE" /> </root> 

relevant Maven dependencies:

    <dependency>         <groupId>ch.qos.logback</groupId>         <artifactId>logback-core</artifactId>         <version>1.0.12</version>     </dependency>      <dependency>         <groupId>ch.qos.logback</groupId>         <artifactId>logback-classic</artifactId>         <version>1.0.12</version>     </dependency> 

Answer 2

I see a lot of answers telling you to use Log4J, but you can use Java's own logger to do this by simply creating a FileHandler:

Handler handler =     new FileHandler("%h/MyService-%g.log", 10 * 1024 * 1024, 10); handler.setLevel(Level.ALL); Logger.getLogger("").addHandler(handler);