CUI Logging Skill

REFERENCE MODE: This skill provides reference material. Load specific standards on-demand based on current task.

CUI-specific logging standards for projects using the CUI logging framework (cui-java-tools). This skill covers CuiLogger usage, LogRecord patterns, and DSL-style LogMessages classes.

Enforcement

Execution mode: Reference library; load standards progressively based on current logging task.

Prohibited actions:

• Do not use SLF4J or Log4j directly; all logging must use CuiLogger
• Do not use string literals for INFO/WARN/ERROR/FATAL; must use LogRecord constants
• Do not load all standards at once; load progressively based on current task

Constraints:

• Exception parameter must always come first in logging calls
• DEBUG/TRACE levels use direct logger (no LogRecord required)
• INFO and above must use LogRecord from a DSL-style LogMessages class
• All LogRecord usage must be covered by LogAsserts in tests

Prerequisites

This skill requires CUI library dependencies:

• de.cuioss:cui-java-tools (CuiLogger, LogRecord)

Workflow

Step 1: Load Core Logging Standards

CRITICAL: Load these standards for any logging-related work.

Read: standards/logging-standards.md

This provides the foundational rules:

• MUST use CuiLogger (SLF4J/Log4j FORBIDDEN)
• MUST use LogRecord for INFO/WARN/ERROR/FATAL levels
• Exception parameter MUST come first in all logging calls

Step 2: Load Additional Standards (As Needed)

DSL Constants Pattern (load when creating LogMessages classes):

Read: standards/dsl-constants.md

Use when: Implementing DSL-style LogMessages classes with nested static classes and @UtilityClass pattern.

LogMessages Documentation (load when documenting):

Read: standards/logmessages-documentation.md

Use when: Writing AsciiDoc documentation for LogMessages classes.

Logging Maintenance (load for migration/refactoring):

Read: standards/logging-maintenance-reference.md

Use when: Large-scale logger migration, LogRecord implementation, or maintenance work.

Key Rules Summary

CuiLogger Usage

// CORRECT
private static final CuiLogger LOGGER = new CuiLogger(MyClass.class);

// FORBIDDEN - Never use SLF4J or Log4j directly
private static final Logger LOGGER = LoggerFactory.getLogger(MyClass.class);

LogRecord for Structured Messages

// CORRECT - Use LogRecord for INFO and above
LOGGER.info(INFO.USER_LOGIN, username);
LOGGER.warn(WARN.RATE_LIMIT, resourceName);
LOGGER.error(exception, ERROR.OPERATION_FAILED);

// DEBUG/TRACE - Direct logging allowed (no LogRecord needed)
LOGGER.debug("Debug message: %s", value);

Exception Handling

// CORRECT - Exception FIRST
LOGGER.error(exception, ERROR.OPERATION_FAILED);

// WRONG - Exception position
LOGGER.error(ERROR.OPERATION_FAILED, exception);

Related Skills

• pm-dev-java:java-core - General Java patterns (no CUI dependencies)
• pm-dev-java-cui:cui-testing - CUI test utilities including JUL testing with LogAsserts

Standards Reference

Standard	Purpose
logging-standards.md	Core CuiLogger, LogRecord rules, and compliance verification
dsl-constants.md	DSL-style constant organization
logmessages-documentation.md	AsciiDoc documentation patterns
logging-maintenance-reference.md	Migration and maintenance

Review Rules

The review rules of the java-cui domain — what a code review looks for in changed code that logs through the CUI logging framework. The block follows the harvestable block contract — see review-rubric.md § 10 "Harvestable review-rule blocks" for its rules, which are not restated here.

• A logging call that passes the exception after the message or LogRecord instead of first, so the exception is consumed as a format argument and its stack trace is never logged.
• An INFO, WARN, ERROR or FATAL call that logs a string literal instead of a LogRecord from a LogMessages class, so the message carries no identifier and cannot be asserted in a test or looked up in the documentation.
• A CuiLogger message that uses an SLF4J-style {} placeholder instead of %s, so the argument is never substituted and the logged line shows the literal braces.
• Two LogRecord constants in one LogMessages class that share an identifier number, so the identifier no longer names exactly one message and a log search returns both.
• A LogRecord the change adds or edits with no LogAsserts check in a test, so a changed message text, level or identifier ships without any test turning red.