Package org.apache.lucene.misc.search

# Class DocValuesStats<T>

java.lang.Object
org.apache.lucene.misc.search.DocValuesStats<T>

Direct Known Subclasses:
  `DocValuesStats.NumericDocValuesStats`, `DocValuesStats.SortedDocValuesStats`, `DocValuesStats.SortedNumericDocValuesStats`, `DocValuesStats.SortedSetDocValuesStats`

public abstract class DocValuesStats<T> extends Object
Holds statistics for a DocValues field.

## Nested Class Summary

Nested Classes
Modifier and Type
Class
Description
`static final class`
`DocValuesStats.DoubleDocValuesStats`
Holds DocValues statistics for a numeric field storing `double` values.
`static final class`
`DocValuesStats.LongDocValuesStats`
Holds DocValues statistics for a numeric field storing `long` values.
`static class`
`DocValuesStats.NumericDocValuesStats<T extends Number>`
Holds statistics for a numeric DocValues field.
`static class`
`DocValuesStats.SortedDocValuesStats`
Holds statistics for a sorted DocValues field.
`static final class`
`DocValuesStats.SortedDoubleDocValuesStats`
Holds DocValues statistics for a sorted-numeric field storing `double` values.
`static final class`
`DocValuesStats.SortedLongDocValuesStats`
Holds DocValues statistics for a sorted-numeric field storing `long` values.
`static class`
`DocValuesStats.SortedNumericDocValuesStats<T extends Number>`
Holds statistics for a sorted-numeric DocValues field.
`static class`
`DocValuesStats.SortedSetDocValuesStats`
Holds statistics for a sorted-set DocValues field.

## Field Summary

Fields
Modifier and Type
Field
Description
`protected final String`
`field`
`protected T`
`max`
`protected T`
`min`

## Constructor Summary

Constructors
Modifier
Constructor
Description
`protected`
`DocValuesStats(String field, T initialMin, T initialMax)`

## Method Summary

Modifier and Type
Method
Description
`final int`
`count()`
The number of documents which have a value of the field.
`protected abstract void`
`doAccumulate(int count)`
Called after `accumulate(int)` was processed and verified that the document has a value for the field.
`final String`
`field()`
The field for which these stats were computed.
`protected abstract boolean`
`hasValue(int doc)`
Returns whether the given document has a value for the requested DocValues field.
`protected abstract boolean`
`init(LeafReaderContext context)`
Initializes this object with the given reader context.
`final T`
`max()`
The maximum value of the field.
`final T`
`min()`
The minimum value of the field.
`final int`
`missing()`
The number of documents which do not have a value of the field.

### Methods inherited from class java.lang.Object

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

## Field Details

### field

protected final String field

### min

protected T min

### max

protected T max

## Constructor Details

### DocValuesStats

protected DocValuesStats(String field, T initialMin, T initialMax)

## Method Details

### doAccumulate

protected abstract void doAccumulate(int count) throws IOException
Called after `accumulate(int)` was processed and verified that the document has a value for the field. Implementations should update the statistics based on the value of the current document.

Parameters:
  `count` - the updated number of documents with value for this field.
Throws:
  `IOException`

### init

protected abstract boolean init(LeafReaderContext context) throws IOException
Initializes this object with the given reader context. Returns whether stats can be computed for this segment (i.e. it does have the requested DocValues field).

Throws:
  `IOException`

### hasValue

protected abstract boolean hasValue(int doc) throws IOException
Returns whether the given document has a value for the requested DocValues field.

Throws:
  `IOException`

### field

public final String field()
The field for which these stats were computed.

### count

public final int count()
The number of documents which have a value of the field.

### missing

public final int missing()
The number of documents which do not have a value of the field.

### min

public final T min()
The minimum value of the field. Undefined when `count()` is zero.

### max

public final T max()
The maximum value of the field. Undefined when `count()` is zero.