gflog

# GFLog logging Add logging statements using our company standard GFLog library. ## Process 1. Identify logging statements that need creation or conversion 2. Replace string concatenation with a-la printf-style formatting (with only %s available for all types) 3. Apply appropriate formatter methods (withTimestamp, withDecimal64, etc.) 4. Add guard conditions for expensive operations 5. Verify log level consistency ## Guidelines * When you see string concatenation in existing log statement you need to replace it with printf-like approach followed by GFLog. For example: LOGGER.log(Level.FINE, "Found " + list.size() + " instruments"); should be LOG.debug("Found %s instruments").with(list.size()); ## Formatters by Data Type **Timestamps** (epoch millis as `long`): - Use: `.withTimestamp(value)` - Example: `.withTimestamp(System.currentTimeMillis())` **DFP-encoded money/quantities** (`long` representing Decimal64): - Use: `.withDecimal64(value)` - Example: `.withDecimal64(price)` for prices, `.withDecimal64(quantity)` for quantities **Alphanumeric identifiers** (`@Alphanumeric long`): - Use: `.withAlphanumeric(value)` - Example: `.withAlphanumeric(instrumentId)` for encoded symbol/ID **Regular values**: - Use: `.with(value)` ## Quick Start **Initialize logger** (at class level): ```java protected static final Log LOG = LogFactory.getLog(CurrentClass.class); ``` **Basic logging**: ```java LOG.info("Hello %s! Current time is %s") .with(name) .withTimestamp(System.currentTimeMillis()); ``` **With guard for expensive operations**: ```java if (LOG.isDebugEnabled()) { LOG.debug("Computed result: %s").with(expensiveComputation()); } ``` Here we need to make sure that function `expensiveComputation()` does not perform any logging of its own inside its body. GFLog is not re-entrant. In such cases it is better to move function call outside of logging statement: ```java if (LOG.isDebugEnabled()) { var x = expensiveComputation(); LOG.debug("Computed result: %s").with(x); } ``` ## Typical pitfalls * Only `%s` is supported as a format specifier — type-specific specifiers (`%d`, `%04d`, `%f`, etc.) are not recognized. * Incorrect: `LOG.info("Value is %04d").with(value)` * Correct: `LOG.info("Value is %s").with(value)` * Every `.with*()` call must have a matching `%s` placeholder in the format string. * Incorrect: `LOG.error("Error").with(exception)` * Correct: `LOG.error("Error: %s").with(exception)` * Use typed appenders instead of `.with()` for timestamps and DFP values: * Epoch millis → `.withTimestamp(value)`, epoch nanos → `.withTimestampNs(value)` * `Decimal64`-encoded `long` → `.withDecimal64(value)` * Incorrect: `LOG.info("Message time is %s").with(message.getTimestamp())` * Correct: `LOG.info("Message time is %s").withTimestamp(message.getTimestamp())`