com.launchdarkly.logging

Class LogCapture

java.lang.Object

com.launchdarkly.logging.LogCapture

All Implemented Interfaces:

LDLogAdapter

public final class LogCapture
extends java.lang.Object
implements LDLogAdapter

A mechanism for capturing logger output in memory.

Calling Logs.capture() provides a LogCapture object that accumulates all log output from any code that is configured to use it as the log adapter. This is mainly intended for testing.

All messages that come to this object are captured regardless of the log level. If you want to filter out messages below a certain level, you can apply Logs.level(LDLogAdapter, LDLogLevel) and pass the resulting filtered adapter to whatever component will be doing the logging, in place of the original LogCapture object.

Example of usage in the server-side Java SDK:

     LogCapture logSink = Logs.capture();
     LDConfig config = new LDConfig.Builder()
       .logging(
         Components.logging().adapter(logSink)
       )
       .build();
     // create the LDClient and do some things that might produce log output...
     // now, retrieve the captured output
     List<LogCapture.Message> messages = logSink.getMessages();
 

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	LogCapture.Message Information about a captured log message.

Nested classes/interfaces inherited from interface com.launchdarkly.logging.LDLogAdapter

LDLogAdapter.Channel, LDLogAdapter.IsConfiguredExternally

Method Summary

Modifier and Type	Method and Description
LogCapture.Message	awaitMessage(LDLogLevel level, long timeoutMilliseconds) Removes and returns a captured log message of the specified level in FIFO order, waiting if necessary until one is available.
LogCapture.Message	awaitMessage(long timeoutMilliseconds) Removes and returns a captured log message in FIFO order, waiting if necessary until one is available.
java.util.List<LogCapture.Message>	getMessages() Returns all captured messages.
java.util.List<java.lang.String>	getMessageStrings() Returns all captured messages converted to strings.
LDLogAdapter.Channel	newChannel(java.lang.String name) Called internally by the SDK.
LogCapture.Message	requireMessage(LDLogLevel level, long timeoutMilliseconds) Same as awaitMessage(LDLogLevel, long), but throws an exception on timeout.
LogCapture.Message	requireMessage(long timeoutMilliseconds) Same as awaitMessage(long), but throws an exception on timeout.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

newChannel

public LDLogAdapter.Channel newChannel(java.lang.String name)

Called internally by the SDK.

Specified by:

newChannel in interface LDLogAdapter

Parameters:

name - a logger name assigned by the SDK

Returns:

an implementation of LDLogAdapter.Channel

getMessages

public java.util.List<LogCapture.Message> getMessages()

Returns all captured messages.

Returns:

a copy of the messages

getMessageStrings

public java.util.List<java.lang.String> getMessageStrings()

Returns all captured messages converted to strings.

The format is always "LEVEL:text".

Returns:

a copy of the messages as strings

awaitMessage

public LogCapture.Message awaitMessage(long timeoutMilliseconds)

Removes and returns a captured log message in FIFO order, waiting if necessary until one is available.

This method and requireMessage(long) allow you to use LogCapture like a blocking queue, so a test can wait for log output that is being generated by another thread.

Parameters:

timeoutMilliseconds - the maximum time to wait

Returns:

the next available log message, or null if none

awaitMessage

public LogCapture.Message awaitMessage(LDLogLevel level,
                                       long timeoutMilliseconds)

Removes and returns a captured log message of the specified level in FIFO order, waiting if necessary until one is available.

This method and requireMessage(long) allow you to use LogCapture like a blocking queue, so a test can wait for log output that is being generated by another thread.

Parameters:

level - the desired message level, or null for any

timeoutMilliseconds - the maximum time to wait

Returns:

the next available log message, or null if none

requireMessage

public LogCapture.Message requireMessage(long timeoutMilliseconds)

Same as awaitMessage(long), but throws an exception on timeout.

Parameters:

timeoutMilliseconds - the maximum time to wait

Returns:

the next available log message

Throws:

java.lang.AssertionError - if no log message was available within the timeout

requireMessage

public LogCapture.Message requireMessage(LDLogLevel level,
                                         long timeoutMilliseconds)

Same as awaitMessage(LDLogLevel, long), but throws an exception on timeout.

Parameters:

level - the desired message level, or null for any

timeoutMilliseconds - the maximum time to wait

Returns:

the next available log message

Throws:

java.lang.AssertionError - if no log message was available within the timeout