Use System property inside log4j config preperties/xml

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  <appender name="DAILY_FILE" class="org.apache.log4j.DailyRollingFileAppender">
  <param name="Threshold" value="debug" />
  <param name="File" value="${MY_SYS_VAR}/Logs/xyz.log"/>
  <param name="ImmediateFlush" value="true"/>
  <param name="Append" value="true"/>
  <param name="DatePattern" value="'.'yyyy-MM-dd"/>
  <layout class="org.apache.log4j.PatternLayout">
  <param name="ConversionPattern" value="PFS- [%t]-[%d][%-5p][%-25c][%t]: %m\n" />
      </layout>
  </appender>
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  <appender name="DAILY_FILE" class="org.apache.log4j.DailyRollingFileAppender">
  <param name="Threshold" value="debug" />
  <param name="File" value="/opt/Logs/xyz.log"/>
  <param name="ImmediateFlush" value="true"/>
  <param name="Append" value="true"/>
  <param name="DatePattern" value="'.'yyyy-MM-dd"/>
  <layout class="org.apache.log4j.PatternLayout">
  <param name="ConversionPattern" value="PFS-[%d][%-5p][%-25c][%t]: %m\n" />
      </layout>
  </appender>

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