Logging with Log4j in Selenium Java - Practice Problems & Coding Challenges

Challenge - 5 Problems

💻 Command Output

intermediate

Log4j Basic Configuration Output

Given this Log4j2 configuration snippet, what will be the output when the logger logs an info message?

<Configuration status="WARN">
  <Appenders>
    <Console name="Console" target="SYSTEM_OUT">
      <PatternLayout pattern="%d{HH:mm:ss} %-5level %logger{36} - %msg%n"/>
    </Console>
  </Appenders>
  <Loggers>
    <Root level="info">
      <AppenderRef ref="Console"/>
    </Root>
  </Loggers>
</Configuration>

Selenium Java

Logger logger = LogManager.getLogger("MyLogger");
logger.info("Test message");

A A console output like: "14:30:15 INFO MyLogger - Test message"

B A console output like: "14:30:15 DEBUG MyLogger - Test message"

C No output because the level is set to WARN

D An error occurs because the pattern layout is invalid

💡 Hint

Check the root logger level and the message level.

The root logger is set to level INFO, so info messages are logged. The pattern layout formats the output with time, level, logger name, and message.

❓ Troubleshoot

intermediate

Log4j2 Logger Not Printing Messages

You have this Java code snippet using Log4j2:

Logger logger = LogManager.getLogger(MyClass.class);
logger.debug("Debug message");

The log file remains empty after running the program. What is the most likely cause?

A The logger level is set higher than DEBUG, so debug messages are ignored

B The logger name is incorrect and does not match the configuration

C The log file path is missing in the configuration

D The logger instance was not created with LogManager

💡 Hint

Check the configured log level and the message level.

If the configured log level is INFO or higher, DEBUG messages will not be logged, causing the log file to remain empty.

❓ Configuration

advanced

Log4j2 Rolling File Appender Configuration

Which Log4j2 XML configuration snippet correctly sets up a rolling file appender that rolls over daily and keeps 7 days of logs?

A

<Appenders>
  <RollingFile name="RollingFile" fileName="logs/app.log" filePattern="logs/app-%i.log.gz">
    <PatternLayout pattern="%d %p %c{1.} [%t] %m%n"/>
    <Policies>
      <SizeBasedTriggeringPolicy size="10MB"/>
    </Policies>
    <DefaultRolloverStrategy max="7"/>
  </RollingFile>
</Appenders>

B

<Appenders>
  <RollingFile name="RollingFile" fileName="logs/app.log" filePattern="logs/app-%d{yyyy-MM-dd}.log.gz">
    <PatternLayout pattern="%d %p %c{1.} [%t] %m%n"/>
    <Policies>
      <TimeBasedTriggeringPolicy interval="1"/>
    </Policies>
    <DefaultRolloverStrategy max="7"/>
  </RollingFile>
</Appenders>

C

<Appenders>
  <File name="File" fileName="logs/app.log">
    <PatternLayout pattern="%d %p %c{1.} [%t] %m%n"/>
  </File>
</Appenders>

D

<Appenders>
  <RollingFile name="RollingFile" fileName="logs/app.log" filePattern="logs/app-%d{MM-dd-yyyy}.log">
    <PatternLayout pattern="%d %p %c{1.} [%t] %m%n"/>
    <Policies>
      <TimeBasedTriggeringPolicy interval="7"/>
    </Policies>
    <DefaultRolloverStrategy max="30"/>
  </RollingFile>
</Appenders>

💡 Hint

Look for daily rollover and max 7 files retention.

Option B uses TimeBasedTriggeringPolicy with interval 1 for daily rollover and DefaultRolloverStrategy max 7 to keep 7 days of logs.

🔀 Workflow

advanced

Integrating Log4j2 with Selenium Tests

You want to add Log4j2 logging to your Selenium Java tests to log browser actions. Which step is NOT required in the integration workflow?

A Add Log4j2 dependencies to your project build file (e.g., pom.xml or build.gradle)

B Create a Log4j2 configuration file (log4j2.xml) in the resources directory

C Replace all Selenium WebDriver calls with Log4j2 API calls

D Create a Logger instance in your test classes and add logging statements

💡 Hint

Consider what logging does versus what Selenium does.

You do not replace Selenium WebDriver calls with Log4j2 calls; logging is added alongside Selenium calls to record actions.

✅ Best Practice

expert

Best Practice for Sensitive Data in Log4j2 Logs

Which is the best practice to avoid logging sensitive data (like passwords) in Log4j2 logs during automated tests?

A Store sensitive data in plain text in logs but encrypt the log files on disk

B Log all data and delete log files manually after tests

C Disable logging completely during tests to avoid sensitive data exposure

D Use a custom log filter to mask or exclude sensitive data before logging

💡 Hint

Think about controlling what gets logged rather than deleting logs later.

Using a custom filter to mask or exclude sensitive data ensures sensitive info never appears in logs, which is safer and more reliable.