io.ghostwriter

Interface Tracer

All Known Implementing Classes:

NoopTracer

public interface Tracer

Method Summary

Modifier and Type	Method and Description
void	entering(java.lang.Object source, java.lang.String method, java.lang.Object... params) Creates an entering trace message.
void	exiting(java.lang.Object source, java.lang.String method) Creates an exiting trace message.
void	onError(java.lang.Object source, java.lang.String method, java.lang.Throwable error) Triggered when an unhandled exception occurs.
<T> void	returning(java.lang.Object source, java.lang.String method, T returnValue)
void	timeout(java.lang.Object source, java.lang.String method, long timeoutThreshold, long timeout) Triggered when the time between the entering and exiting events exceeds a certain amount of time in milliseconds.
void	valueChange(java.lang.Object source, java.lang.String method, java.lang.String variable, java.lang.Object value) Creates a value change trace message immediately after a successful update.

Method Detail

entering

void entering(java.lang.Object source,
              java.lang.String method,
              java.lang.Object... params)

Creates an entering trace message.

Parameters:

source - The object triggering the tracing event.

method - The method name, where the tracing event happened.

params - Parameters of the method in question. They are passed as {name, value} pairs in sequence.

exiting

void exiting(java.lang.Object source,
             java.lang.String method)

Creates an exiting trace message. Used in case of methods with Void return value.

Parameters:

source - The object triggering the tracing event.

method - The method name, where the tracing event happened.

valueChange

void valueChange(java.lang.Object source,
                 java.lang.String method,
                 java.lang.String variable,
                 java.lang.Object value)

Creates a value change trace message immediately after a successful update.

Parameters:

source - The object triggering the event.

method - The method name, where the tracing event happened.

variable - The name of the variable that had a new value assigned

value - The value that was assigned to the variable

returning

<T> void returning(java.lang.Object source,
                   java.lang.String method,
                   T returnValue)

Type Parameters:

T - Type of the return value

Parameters:

source - The object triggering the event

method - The method name, where the tracing event happened

returnValue - The value that the current method returns

onError

void onError(java.lang.Object source,
             java.lang.String method,
             java.lang.Throwable error)

Triggered when an unhandled exception occurs. The primary use case is for runtime implementations, by triggering state saving only in cases where the context details are valuable.

Parameters:

source - The object triggering the event.

method - The method name, where the tracing event happened.

error - The capture exception object.

timeout

void timeout(java.lang.Object source,
             java.lang.String method,
             long timeoutThreshold,
             long timeout)

Triggered when the time between the entering and exiting events exceeds a certain amount of time in milliseconds. This is an opt-in feature, that is enabled by annotating the methods that need to be watched.

Parameters:

source - The object triggering the event

method - The method name, where the timeout event happened

timeoutThreshold - Threshold value for the current method

timeout - The timeout value in milliseconds that triggered the event. This is always larger than the threshold value.