FieldInfos (Lucene 8.9.0 API)乐学网一站式学习平台

java.lang.Object
- org.apache.lucene.index.FieldInfos

All Implemented Interfaces:

Iterable<FieldInfo>
```
public class FieldInfos
extends Object
implements Iterable<FieldInfo>
```
Collection of FieldInfos (accessible by number or by name).

WARNING: This API is experimental and might change in incompatible ways in the next release.

Field Summary

Fields
Modifier and Type Field and Description

static FieldInfos EMPTY
An instance without any fields.

Fields
Modifier and Type	Field and Description
`static FieldInfos`	`EMPTY` An instance without any fields.

Constructor Summary

Constructors
Constructor and Description

FieldInfos(FieldInfo[] infos)
Constructs a new FieldInfos from an array of FieldInfo objects

Constructors
Constructor and Description
`FieldInfos(FieldInfo[] infos)` Constructs a new FieldInfos from an array of FieldInfo objects

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`FieldInfo`	`fieldInfo(int fieldNumber)` Return the fieldinfo object referenced by the fieldNumber.
`FieldInfo`	`fieldInfo(String fieldName)` Return the fieldinfo object referenced by the field name
`static Collection<String>`	`getIndexedFields(IndexReader reader)` Returns a set of names of fields that have a terms index.
`static FieldInfos`	`getMergedFieldInfos(IndexReader reader)` Call this to get the (merged) FieldInfos for a composite reader.
`String`	`getSoftDeletesField()` Returns the soft-deletes field name if exists; otherwise returns null
`boolean`	`hasDocValues()` Returns true if any fields have DocValues
`boolean`	`hasFreq()` Returns true if any fields have freqs
`boolean`	`hasNorms()` Returns true if any fields have norms
`boolean`	`hasOffsets()` Returns true if any fields have offsets
`boolean`	`hasPayloads()` Returns true if any fields have payloads
`boolean`	`hasPointValues()` Returns true if any fields have PointValues
`boolean`	`hasProx()` Returns true if any fields have positions
`boolean`	`hasVectors()` Returns true if any fields have vectors
`Iterator<FieldInfo>`	`iterator()` Returns an iterator over all the fieldinfo objects present, ordered by ascending field number
`int`	`size()` Returns the number of fields

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface java.lang.Iterable
forEach, spliterator

- Field Detail
  - EMPTY
```
public static final FieldInfos EMPTY
```
    An instance without any fields.
- Constructor Detail
  - FieldInfos
```
public FieldInfos(FieldInfo[] infos)
```
    Constructs a new FieldInfos from an array of FieldInfo objects
- Method Detail
  - getMergedFieldInfos
```
public static FieldInfos getMergedFieldInfos(IndexReader reader)
```
    Call this to get the (merged) FieldInfos for a composite reader.
    NOTE: the returned field numbers will likely not correspond to the actual field numbers in the underlying readers, and codec metadata (FieldInfo.getAttribute(String) will be unavailable.
  - getIndexedFields
```
public static Collection<String> getIndexedFields(IndexReader reader)
```
    Returns a set of names of fields that have a terms index. The order is undefined.
  - hasFreq
```
public boolean hasFreq()
```
    Returns true if any fields have freqs
  - hasProx
```
public boolean hasProx()
```
    Returns true if any fields have positions
  - hasPayloads
```
public boolean hasPayloads()
```
    Returns true if any fields have payloads
  - hasOffsets
```
public boolean hasOffsets()
```
    Returns true if any fields have offsets
  - hasVectors
```
public boolean hasVectors()
```
    Returns true if any fields have vectors
  - hasNorms
```
public boolean hasNorms()
```
    Returns true if any fields have norms
  - hasDocValues
```
public boolean hasDocValues()
```
    Returns true if any fields have DocValues
  - hasPointValues
```
public boolean hasPointValues()
```
    Returns true if any fields have PointValues
  - getSoftDeletesField
```
public String getSoftDeletesField()
```
    Returns the soft-deletes field name if exists; otherwise returns null
  - size
```
public int size()
```
    Returns the number of fields
  - iterator
```
public Iterator<FieldInfo> iterator()
```
    Returns an iterator over all the fieldinfo objects present, ordered by ascending field number
    
    Specified by:
    
    iterator in interface Iterable<FieldInfo>
  - fieldInfo
```
public FieldInfo fieldInfo(String fieldName)
```
    Return the fieldinfo object referenced by the field name
    
    Returns:
    
    the FieldInfo object or null when the given fieldName doesn't exist.
  - fieldInfo
```
public FieldInfo fieldInfo(int fieldNumber)
```
    Return the fieldinfo object referenced by the fieldNumber.
    
    Parameters:
    
    fieldNumber - field's number.
    
    Returns:
    
    the FieldInfo object or null when the given fieldNumber doesn't exist.
    
    Throws:
    
    IllegalArgumentException - if fieldNumber is negative

Class FieldInfos

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Methods inherited from interface java.lang.Iterable

Field Detail

EMPTY

Constructor Detail

FieldInfos

Method Detail

getMergedFieldInfos

getIndexedFields

hasFreq

hasProx

hasPayloads

hasOffsets

hasVectors

hasNorms

hasDocValues

hasPointValues

getSoftDeletesField

size

iterator

fieldInfo

fieldInfo