Package org.apache.lucene.store

Record Class IOContext

java.lang.Object

java.lang.Record

org.apache.lucene.store.IOContext

Record Components:

context - An object of a enumerator Context type

mergeInfo - must be given when context == MERGE

flushInfo - must be given when context == FLUSH

readAdvice - Advice regarding the read access pattern

public record IOContext(IOContext.Context context, MergeInfo mergeInfo, FlushInfo flushInfo, ReadAdvice readAdvice)
extends Record

IOContext holds additional details on the merge/search context. An IOContext object can never be passed as a null parameter to either Directory.openInput(String, IOContext) or Directory.createOutput(String, IOContext)

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static enum	IOContext.Context	Context is a enumerator which specifies the context in which the Directory is being used for.

Field Summary

Fields

Modifier and Type	Field	Description
static final IOContext	DEFAULT	A default context for normal reads/writes.
static final IOContext	READONCE	A default context for reads with ReadAdvice.SEQUENTIAL.

Constructor Summary

Constructors

Constructor	Description
IOContext(FlushInfo flushInfo)	Creates an IOContext for flushing.
IOContext(IOContext.Context context, MergeInfo mergeInfo, FlushInfo flushInfo, ReadAdvice readAdvice)	Creates an instance of a IOContext record class.
IOContext(MergeInfo mergeInfo)	Creates an IOContext for merging.

Method Summary

Modifier and Type	Method	Description
IOContext.Context	context()	Returns the value of the context record component.
final boolean	equals(Object o)	Indicates whether some other object is "equal to" this one.
FlushInfo	flushInfo()	Returns the value of the flushInfo record component.
final int	hashCode()	Returns a hash code value for this object.
MergeInfo	mergeInfo()	Returns the value of the mergeInfo record component.
ReadAdvice	readAdvice()	Returns the value of the readAdvice record component.
final String	toString()	Returns a string representation of this record class.
IOContext	withReadAdvice(ReadAdvice advice)	Return an updated IOContext that has the provided ReadAdvice if the IOContext.Context is a IOContext.Context.DEFAULT context, otherwise return this existing instance.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Details

DEFAULT

public static final IOContext DEFAULT

A default context for normal reads/writes. Use withReadAdvice(ReadAdvice) to specify another ReadAdvice.

It will use ReadAdvice.RANDOM by default, unless set by system property org.apache.lucene.store.defaultReadAdvice.

READONCE

public static final IOContext READONCE

A default context for reads with ReadAdvice.SEQUENTIAL.

This context should only be used when the read operations will be performed in the same thread as the thread that opens the underlying storage.

Constructor Details

IOContext

public IOContext(IOContext.Context context,
 MergeInfo mergeInfo,
 FlushInfo flushInfo,
 ReadAdvice readAdvice)

Creates an instance of a IOContext record class.

Parameters:

context - the value for the context record component

mergeInfo - the value for the mergeInfo record component

flushInfo - the value for the flushInfo record component

readAdvice - the value for the readAdvice record component

IOContext

public IOContext(FlushInfo flushInfo)

Creates an IOContext for flushing.

IOContext

public IOContext(MergeInfo mergeInfo)

Creates an IOContext for merging.

Method Details

withReadAdvice

public IOContext withReadAdvice(ReadAdvice advice)

Return an updated IOContext that has the provided ReadAdvice if the IOContext.Context is a IOContext.Context.DEFAULT context, otherwise return this existing instance. This helps preserve a ReadAdvice.SEQUENTIAL advice for merging, which is always the right choice, while allowing IndexInputs open for searching to use arbitrary ReadAdvices.

toString

public final String toString()

Returns a string representation of this record class. The representation contains the name of the class, followed by the name and value of each of the record components.

Specified by:

toString in class Record

Returns:

a string representation of this object

hashCode

public final int hashCode()

Returns a hash code value for this object. The value is derived from the hash code of each of the record components.

Specified by:

hashCode in class Record

Returns:

a hash code value for this object

equals

public final boolean equals(Object o)

Indicates whether some other object is "equal to" this one. The objects are equal if the other object is of the same class and if all the record components are equal. All components in this record class are compared with Objects::equals(Object,Object).

Specified by:

equals in class Record

Parameters:

o - the object with which to compare

Returns:

true if this object is the same as the o argument; false otherwise.

context

public IOContext.Context context()

Returns the value of the context record component.

Returns:

the value of the context record component

mergeInfo

public MergeInfo mergeInfo()

Returns the value of the mergeInfo record component.

Returns:

the value of the mergeInfo record component

flushInfo

public FlushInfo flushInfo()

Returns the value of the flushInfo record component.

Returns:

the value of the flushInfo record component

readAdvice

public ReadAdvice readAdvice()

Returns the value of the readAdvice record component.

Returns:

the value of the readAdvice record component