Logging utilities

The com.ajaxjs.util.log package contains small helpers intended to be used with SLF4J.

Trace context

Trace defines MDC keys traceId, bizAction, and ENABLE_OPERATION_LOG. saveLogToMDC() appends content only when ENABLE_OPERATION_LOG is already present in MDC.

MDC.put(Trace.ENABLE_OPERATION_LOG, "Start: ");
Trace.saveLogToMDC("created order; ");
String operationLog = MDC.get(Trace.ENABLE_OPERATION_LOG);
MDC.remove(Trace.ENABLE_OPERATION_LOG);

MDC is generally thread-local. Propagate or clear it explicitly when work crosses executor threads or request boundaries.

TextBox

TextBox formats diagnostic key-value data using box-drawing characters and ANSI colors.

String output = new TextBox()
        .boxStart("Request")
        .line("id: ", requestId)
        .line("status: ", 200)
        .boxEnd();

It wraps long lines by default, counts common CJK characters as double width, and truncates a single value at 1,500 characters. setWrapLongLines(false) switches to truncation. ANSI output is appropriate for capable terminals, not for every structured log destination.

EnableOperationLog

@EnableOperationLog is a runtime method annotation with an optional title:

@EnableOperationLog("Create order")
public void createOrder() {
}

The annotation is only a marker in this module. An AOP interceptor or other application integration must decide how to process it.