InfoStream (Lucene 9.0.0 core API)

java.lang.Object
- org.apache.lucene.util.InfoStream

All Implemented Interfaces:

Closeable, AutoCloseable

Direct Known Subclasses:

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 InfoStream NO_OUTPUT
Instance of InfoStream that does no logging at all.

Constructor Summary

Constructors
Constructor Description

InfoStream()

Method Summary

All Methods Static Methods Instance Methods Abstract Methods Concrete Methods
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 Detail
  - NO_OUTPUT
```
public static final InfoStream NO_OUTPUT
```
    Instance of InfoStream that does no logging at all.
- Constructor Detail
  - InfoStream
```
public InfoStream()
```
- Method Detail
  - 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()