JAVA¶

Link to the JAVA application using the observation cloud:

• Collect custom metrics data from applications;
• Collect link tracking data from applications;
• Manage all logs for the application.

Configuration¶

Metric Collection¶

You can view jvm doc

Link Tracking Collection¶

Apply Open Correspondence Collector, then use the JAVA agent tool to get traces information and send it to the observation cloud.

Logging¶

opentelemetry-java (hereinafter referred to as "Agent") is injected into the application through javaagent. After the application generates trace information, the traceId and spanId can be passed as parameters to log so that log will be output with traceId and spanId.

????+ Info "About MDC"

It contains thread local context information and copies it to each log event captured by the log library.

OTEL JAVA Agent injects several pieces of information about the current span into the MDC copy of each logged event:

• trace_idcurrent tracking ID (same as Span.current().getSpanContext().getTraceId());
• span_idcurrent span ID (same as Span.current().getSpanContext().getSpanId());
• trace_flagsCurrent trace flag, formatted according to W3C trace flag format (same as Span.current().getSpanContext().getTraceFlags().asHex()).

These three pieces of information can be included in the log statements generated by the log library by specifying them in the pattern/format.

Tip: For SpringBoot configurations that use logback, you can add MDC to the log line logging.pattern.level by simply overwriting:

logging.pattern.level = trace_id=%mdc{trace_id} span_id=%mdc{span_id} trace_flags=%mdc{trace_flags} %5p

This allows any service or tool that parses the application log to associate trace/span with log statements.

Log Configuration¶

The APM tool configuration logs pattern differ from each other. Take logback.xml for example:

<property name="log.pattern" value="%d{HH:mm:ss} [%thread] %-5level %logger{10} [traceId=%X{trace_id} spanId=%X{span_id} userId=%X{user-id}] %msg%n" />

<appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
    <encoder>
        <pattern>${log.pattern}</pattern>
        <charset>UTF-8</charset>
    </encoder>
</appender>

<property name="log.pattern" value="%d{yyyy-MM-dd HH:mm:ss.SSS} [%thread] %-5level %logger - [%method,%line] %X{dd.service} %X{dd.trace_id} %X{dd.span_id} - %msg%n" />

<appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
    <encoder>
        <pattern>${log.pattern}</pattern>
        <charset>UTF-8</charset>
    </encoder>
</appender>-

Doc¶

DDTrace Log

springboot-ddtrace-server

springboot-opentelemetry-otlp-server