Package org.apache.lucene.util

Class InfoStream

java.lang.Object

org.apache.lucene.util.InfoStream

All Implemented Interfaces:

Closeable, AutoCloseable

Direct Known Subclasses:

JavaLoggingInfoStream, PrintStreamInfoStream

public abstract class InfoStream
extends Object
implements Closeable

Debugging API for Lucene classes such as IndexWriter and SegmentInfos.

NOTE: Enabling infostreams may cause performance degradation in some components.

NOTE: This API is for internal purposes only and might change in incompatible ways in the next release.

Field Summary

Fields

Modifier and Type	Field	Description
static final InfoStream	NO_OUTPUT	Instance of InfoStream that does no logging at all.

Constructor Summary

Constructors

Constructor	Description
InfoStream()

Method Summary

Modifier and Type	Method	Description
static InfoStream	getDefault()	The default InfoStream used by a newly instantiated classes.
abstract boolean	isEnabled(String component)	returns true if messages are enabled and should be posted to message(java.lang.String, java.lang.String).
abstract void	message(String component, String message)	prints a message
static void	setDefault(InfoStream infoStream)	Sets the default InfoStream used by a newly instantiated classes.

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.io.Closeable

close

Field Details

NO_OUTPUT

public static final InfoStream NO_OUTPUT

Instance of InfoStream that does no logging at all.

Constructor Details

InfoStream

public InfoStream()

Method Details

message

public abstract void message(String component,
 String message)

prints a message

isEnabled

public abstract boolean isEnabled(String component)

returns true if messages are enabled and should be posted to message(java.lang.String, java.lang.String).

getDefault

public static InfoStream getDefault()

The default InfoStream used by a newly instantiated classes.

See Also:

• setDefault(org.apache.lucene.util.InfoStream)

setDefault

public static void setDefault(InfoStream infoStream)

Sets the default InfoStream used by a newly instantiated classes. It cannot be null, to disable logging use NO_OUTPUT.

See Also:

• getDefault()