4.6.2. 一些有用的 Logger 配置

以下是一些框架里面比较有用的 loggers，可以用来调试问题。

eclipselink.sql

如果设置成 DEBUG，EclipseLink ORM 框架会打印所有执行的 SQL 语句和执行时间。这个 logger 已经在标准的 logback.xml 里面定义了，所以使用的时候只需要修改它的日志级别，示例：

<configuration>
    ...
    <logger name="eclipselink.sql" level="DEBUG"/>

日志输出的样例：

2018-09-21 12:48:18.583 DEBUG [http-nio-8080-exec-5/app-core/admin] com.haulmont.cuba.core.app.RdbmsStore - loadList: metaClass=sec$User, view=com.haulmont.cuba.security.entity.User/user.browse, query=select u from sec$User u, max=50
2018-09-21 12:48:18.586 DEBUG [http-nio-8080-exec-5/app-core/admin] eclipselink.sql - <t 891235430, conn 1084868057> SELECT t1.ID AS a1, t1.ACTIVE AS a2, t1.CHANGE_PASSWORD_AT_LOGON AS a3, t1.CREATE_TS AS a4, t1.CREATED_BY AS a5, t1.DELETE_TS AS a6, t1.DELETED_BY AS a7, t1.EMAIL AS a8, t1.FIRST_NAME AS a9, t1.IP_MASK AS a10, t1.LANGUAGE_ AS a11, t1.LAST_NAME AS a12, t1.LOGIN AS a13, t1.LOGIN_LC AS a14, t1.MIDDLE_NAME AS a15, t1.NAME AS a16, t1.PASSWORD AS a17, t1.POSITION_ AS a18, t1.TIME_ZONE AS a19, t1.TIME_ZONE_AUTO AS a20, t1.UPDATE_TS AS a21, t1.UPDATED_BY AS a22, t1.VERSION AS a23, t1.GROUP_ID AS a24, t0.ID AS a25, t0.DELETE_TS AS a26, t0.DELETED_BY AS a27, t0.NAME AS a28, t0.VERSION AS a29 FROM SEC_USER t1 LEFT OUTER JOIN SEC_GROUP t0 ON (t0.ID = t1.GROUP_ID) WHERE (t1.DELETE_TS IS NULL) LIMIT ? OFFSET ?
        bind => [50, 0]
2018-09-21 12:48:18.587 DEBUG [http-nio-8080-exec-5/app-core/admin] eclipselink.sql - <t 891235430, conn 1084868057> [1 ms] spent
com.haulmont.cuba.core.sys.AbstractWebAppContextLoader

如果设置成 TRACE，框架会在服务启动时打印文件中定义的应用程序属性和程序模块中定义的属性，可以用来调试启动时候出现的问题。

需要注意的是，应该给一个合适的 appender 的日志级别设置成 TRACE，因为通常 appenders 的日志级别都设定的比较高。比如：

<configuration>
    ...
    <appender name="File" class="ch.qos.logback.core.rolling.RollingFileAppender">
        <filter class="ch.qos.logback.classic.filter.ThresholdFilter">
            <level>TRACE</level>
        </filter>
    ...
    <logger name="com.haulmont.cuba.core.sys.AbstractWebAppContextLoader" level="TRACE"/>

日志输出的样例：

2018-09-21 12:38:59.525 TRACE [localhost-startStop-1] com.haulmont.cuba.core.sys.AbstractWebAppContextLoader - AppProperties of the 'core' block:
cuba.anonymousSessionId=9c91dbdf-3e73-428e-9088-d586da2434c5
cuba.automaticDatabaseUpdate=true
...