FieldAccessDescriptor (Apache Beam 2.20.0)

java.lang.Object
- org.apache.beam.sdk.schemas.FieldAccessDescriptor

All Implemented Interfaces:

java.io.Serializable
```
@Experimental(value=SCHEMAS)
public abstract class FieldAccessDescriptor
extends java.lang.Object
implements java.io.Serializable
```
Used inside of a DoFn to describe which fields in a schema type need to be accessed for processing.
This class always puts the selected fields in a deterministic order.

See Also:

Serialized Form

Nested Class Summary

Nested Classes
Modifier and Type Class and Description

static class FieldAccessDescriptor.FieldDescriptor
Description of a single field.

Nested Classes
Modifier and Type	Class and Description
`static class`	`FieldAccessDescriptor.FieldDescriptor` Description of a single field.

Constructor Summary

Constructors
Constructor and Description

FieldAccessDescriptor()

Constructors
Constructor and Description
`FieldAccessDescriptor()`

Method Summary

All Methods Static Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method and Description
`static FieldAccessDescriptor`	`create()` Return an empty `FieldAccessDescriptor`.
`java.util.List<java.lang.Integer>`	`fieldIdsAccessed()` Return the field ids accessed.
`java.util.Set<java.lang.String>`	`fieldNamesAccessed()` Return the field names accessed.
`abstract boolean`	`getAllFields()` If true, all fields are being accessed.
`abstract boolean`	`getFieldInsertionOrder()`
`abstract java.util.List<FieldAccessDescriptor.FieldDescriptor>`	`getFieldsAccessed()`
`abstract java.util.Map<FieldAccessDescriptor.FieldDescriptor,FieldAccessDescriptor>`	`getNestedFieldsAccessed()`
`java.util.Map<java.lang.Integer,FieldAccessDescriptor>`	`nestedFieldsById()` Return the nested fields keyed by field ids.
`java.util.Map<java.lang.String,FieldAccessDescriptor>`	`nestedFieldsByName()` Return the nested fields keyed by field name.
`boolean`	`referencesSingleField()` Returns true if this descriptor references only a single, non-wildcard field.
`FieldAccessDescriptor`	`resolve(Schema schema)` Resolve the `FieldAccessDescriptor` against a schema.
`java.lang.String`	`toString()`
`static FieldAccessDescriptor`	`withAllFields()`
`static FieldAccessDescriptor`	`withFieldIds(java.lang.Integer... ids)` Return a descriptor that access the specified fields.
`static FieldAccessDescriptor`	`withFieldIds(java.lang.Iterable<java.lang.Integer> ids)` Return a descriptor that access the specified fields.
`FieldAccessDescriptor`	`withFieldNameAs(java.lang.String fieldName, java.lang.String fieldRename)` Add a field with a new name.
`static FieldAccessDescriptor`	`withFieldNames(java.lang.Iterable<java.lang.String> fieldNames)` Return a descriptor that access the specified fields.
`static FieldAccessDescriptor`	`withFieldNames(java.lang.String... names)` Return a descriptor that access the specified fields.
`static FieldAccessDescriptor`	`withFieldNamesAs(java.util.Map<java.lang.String,java.lang.String> fieldNamesAs)`
`static FieldAccessDescriptor`	`withFields(FieldAccessDescriptor.FieldDescriptor... fields)` Returns a `FieldAccessDescriptor` that accesses the specified fields.
`static FieldAccessDescriptor`	`withFields(java.lang.Iterable<FieldAccessDescriptor.FieldDescriptor> fields)` Returns a `FieldAccessDescriptor` that accesses the specified fields.
`FieldAccessDescriptor`	`withNestedField(FieldAccessDescriptor.FieldDescriptor field, FieldAccessDescriptor fieldAccess)`
`FieldAccessDescriptor`	`withNestedField(int nestedFieldId, FieldAccessDescriptor fieldAccess)` Return a descriptor that access the specified nested field.
`FieldAccessDescriptor`	`withNestedField(java.lang.String nestedFieldName, FieldAccessDescriptor fieldAccess)` Return a descriptor that access the specified nested field.
`FieldAccessDescriptor`	`withNestedFieldAs(java.lang.String nestedFieldName, java.lang.String nestedFieldRename, FieldAccessDescriptor fieldAccess)` Like `withNestedField(int, org.apache.beam.sdk.schemas.FieldAccessDescriptor)` along with a rename of the nested field.
`FieldAccessDescriptor`	`withOrderByFieldInsertionOrder()` By default, fields are sorted by name.

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

- Constructor Detail
  - FieldAccessDescriptor
```
public FieldAccessDescriptor()
```
- Method Detail
  - getAllFields
```
public abstract boolean getAllFields()
```
    If true, all fields are being accessed.
  - getFieldsAccessed
```
public abstract java.util.List<FieldAccessDescriptor.FieldDescriptor> getFieldsAccessed()
```
  - getNestedFieldsAccessed
```
public abstract java.util.Map<FieldAccessDescriptor.FieldDescriptor,FieldAccessDescriptor> getNestedFieldsAccessed()
```
  - getFieldInsertionOrder
```
public abstract boolean getFieldInsertionOrder()
```
  - withAllFields
```
public static FieldAccessDescriptor withAllFields()
```
  - withFieldNames
```
public static FieldAccessDescriptor withFieldNames(java.lang.String... names)
```
    Return a descriptor that access the specified fields.
    By default, if the field is a nested row (or a container containing a row), all fields of said rows are accessed. The syntax for a field name allows specifying nested fields and wildcards, as specified in the file-level Javadoc. withNestedField can also be called to specify recursive field access.
  - withFieldNames
```
public static FieldAccessDescriptor withFieldNames(java.lang.Iterable<java.lang.String> fieldNames)
```
    Return a descriptor that access the specified fields.
    By default, if the field is a nested row (or a container containing a row), all fields of said rows are accessed. The syntax for a field name allows specifying nested fields and wildcards, as specified in the file-level Javadoc. withNestedField can also be called to specify recursive field access.
  - withFieldNamesAs
```
public static FieldAccessDescriptor withFieldNamesAs(java.util.Map<java.lang.String,java.lang.String> fieldNamesAs)
```
  - withFieldIds
```
public static FieldAccessDescriptor withFieldIds(java.lang.Integer... ids)
```
    Return a descriptor that access the specified fields.
    By default, if the field is a nested row (or a container containing a row), all fields of said rows are accessed. For finer-grained acccess to nested rows, call withNestedField and pass in a recursive FieldAccessDescriptor.
  - withFieldIds
```
public static FieldAccessDescriptor withFieldIds(java.lang.Iterable<java.lang.Integer> ids)
```
    Return a descriptor that access the specified fields.
    By default, if the field is a nested row (or a container containing a row), all fields of said rows are accessed. For finer-grained acccess to nested rows, call withNestedField and pass in a recursive FieldAccessDescriptor.
  - withFields
```
public static FieldAccessDescriptor withFields(FieldAccessDescriptor.FieldDescriptor... fields)
```
    Returns a FieldAccessDescriptor that accesses the specified fields.
  - withFields
```
public static FieldAccessDescriptor withFields(java.lang.Iterable<FieldAccessDescriptor.FieldDescriptor> fields)
```
    Returns a FieldAccessDescriptor that accesses the specified fields.
  - create
```
public static FieldAccessDescriptor create()
```
    Return an empty FieldAccessDescriptor.
  - withFieldNameAs
```
public FieldAccessDescriptor withFieldNameAs(java.lang.String fieldName,
                                             java.lang.String fieldRename)
```
    Add a field with a new name. This is only valid if the fieldName references a single field (wildcards are not allowed here).
  - withNestedField
```
public FieldAccessDescriptor withNestedField(int nestedFieldId,
                                             FieldAccessDescriptor fieldAccess)
```
    Return a descriptor that access the specified nested field. The nested field must be of type Schema.TypeName.ROW, and the fieldAccess argument specifies what fields of the nested type will be accessed.
  - withNestedField
```
public FieldAccessDescriptor withNestedField(java.lang.String nestedFieldName,
                                             FieldAccessDescriptor fieldAccess)
```
    Return a descriptor that access the specified nested field. The nested field must be of type Schema.TypeName.ROW, and the fieldAccess argument specifies what fields of the nested type will be accessed.
  - withNestedFieldAs
```
public FieldAccessDescriptor withNestedFieldAs(java.lang.String nestedFieldName,
                                               java.lang.String nestedFieldRename,
                                               FieldAccessDescriptor fieldAccess)
```
    Like withNestedField(int, org.apache.beam.sdk.schemas.FieldAccessDescriptor) along with a rename of the nested field.
  - withNestedField
```
public FieldAccessDescriptor withNestedField(FieldAccessDescriptor.FieldDescriptor field,
                                             FieldAccessDescriptor fieldAccess)
```
  - withOrderByFieldInsertionOrder
```
public FieldAccessDescriptor withOrderByFieldInsertionOrder()
```
    By default, fields are sorted by name. If this is set, they will instead be sorted by insertion order. All sorting happens in the resolve(Schema) method.
  - fieldIdsAccessed
```
public java.util.List<java.lang.Integer> fieldIdsAccessed()
```
    Return the field ids accessed. Should not be called until after resolve(org.apache.beam.sdk.schemas.Schema) is called. Iteration order is consistent with getFieldsAccessed().
  - fieldNamesAccessed
```
public java.util.Set<java.lang.String> fieldNamesAccessed()
```
    Return the field names accessed. Should not be called until after resolve(org.apache.beam.sdk.schemas.Schema) is called.
  - nestedFieldsById
```
public java.util.Map<java.lang.Integer,FieldAccessDescriptor> nestedFieldsById()
```
    Return the nested fields keyed by field ids. Should not be called until after resolve(org.apache.beam.sdk.schemas.Schema) is called.
  - nestedFieldsByName
```
public java.util.Map<java.lang.String,FieldAccessDescriptor> nestedFieldsByName()
```
    Return the nested fields keyed by field name. Should not be called until after resolve(org.apache.beam.sdk.schemas.Schema) is called.
  - referencesSingleField
```
public boolean referencesSingleField()
```
    Returns true if this descriptor references only a single, non-wildcard field.
  - resolve
```
public FieldAccessDescriptor resolve(Schema schema)
```
    Resolve the FieldAccessDescriptor against a schema.
    Resolve will resolve all of the field names into field ids, validating that all field names specified in the descriptor exist in the actual schema.
  - toString
```
public java.lang.String toString()
```
    Overrides:
    
    toString in class java.lang.Object

Class FieldAccessDescriptor

Nested Class Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

FieldAccessDescriptor

Method Detail

getAllFields

getFieldsAccessed

getNestedFieldsAccessed

getFieldInsertionOrder

withAllFields

withFieldNames

withFieldNames

withFieldNamesAs

withFieldIds

withFieldIds

withFields

withFields

create

withFieldNameAs

withNestedField

withNestedField

withNestedFieldAs

withNestedField

withOrderByFieldInsertionOrder

fieldIdsAccessed

fieldNamesAccessed

nestedFieldsById

nestedFieldsByName

referencesSingleField

resolve

toString