如何在安卓系统上设置日志文件的最大尺寸？[英] How can I set log file max size on android

问题描述

I'm using microlog4android to log to file. The question is how can set maximum file size?

microlog4android FileAppender class has two methods: getLogSize (which always return -1 ) and clear. I could clear log when it reaches certain size but getLogSize doesn't seem to work.

Is there any better, more mature android logging solution that I'm not aware of?

推荐答案

You can use logback-android with the RollingFileAppender and SizeBasedTriggeringPolicy, but you should be aware of a bug (src) that may cause your working log file to exceed the max file size. A workaround is to subclass the triggering policy to bypass the bug:

package com.example;

import java.io.File;
import ch.qos.logback.core.util.FileSize;

public class SizeBasedTriggeringPolicy<E> extends ch.qos.logback.core.rolling.SizeBasedTriggeringPolicy<E> {
    @Override
    public boolean isTriggeringEvent(final File activeFile, final E event) {
        return (activeFile.length() >= FileSize.valueOf(getMaxFileSize()).getSize());
    }
}

Here's an example config (based on the Logback manual and including the workaround above) that you can put into your AndroidManifest.xml. I tested this in Android 4.0.3 emulator, but I imagine it would also work in earlier versions.

<logback>
    <configuration debug="true">
        <appender
                name="LOGCAT"
                class="ch.qos.logback.classic.android.LogcatAppender" >
            <encoder>
                <pattern>[%method] %msg%n</pattern>
            </encoder>
        </appender>

        <property name="dest.dir" value="/sdcard/test/" />
        <appender name="FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
            <file>${dest.dir}/test.log</file>
            <append>false</append>

            <!-- #########################################
                 # Max of 2 backup zip's (plus uncompressed
                 # working file, ${dest.dir}/test.log)
                 ######################################### -->
            <rollingPolicy class="ch.qos.logback.core.rolling.FixedWindowRollingPolicy">
                <fileNamePattern>${dest.dir}/test.%i.log.zip</fileNamePattern>
                <minIndex>1</minIndex>
                <maxIndex>2</maxIndex>
            </rollingPolicy>

            <!-- #########################################
                 # Rollover when file size reaches 5MB. 
                 # We're using our custom policy here that
                 # works around a bug (LBCORE-123).
                 ######################################### -->
            <!--<triggeringPolicy class="ch.qos.logback.core.rolling.SizeBasedTriggeringPolicy">-->
            <triggeringPolicy class="com.example.SizeBasedTriggeringPolicy">
                <maxFileSize>5MB</maxFileSize>
            </triggeringPolicy>
            <encoder>
                <pattern>%-4relative [%thread] %-5level %logger{35} - %msg%n</pattern>
            </encoder>
        </appender>

        <logger name="com.example.HelloAndroidActivity" level="TRACE">
            <appender-ref ref="FILE" />
        </logger>

        <root level="DEBUG" >
            <appender-ref ref="LOGCAT" />
        </root>
    </configuration>
</logback>

其他推荐答案

May be you can use normal File apis to retrieve file length and then delete/rename it before initializing Logger if it exceeds size limit.