com.northconcepts.datapipeline.core

Class FieldPath

java.lang.Object

com.northconcepts.datapipeline.core.FieldPath

public class FieldPath
extends Object

An abstract representation for the location of a field within a record. Instances can be created by parsing an expression with parse(String) or programmatically by adding name (name(String)) and index (index(int)) segments to an instance.

For example, the field path customer.address[0].city can be created in two ways:

1. FieldPath.parse("customer.address[0].city")
2. new FieldPath().name("customer").name("address").index(0).name("city")

Other examples of parsed field paths include:

• Single field names: firstName
• Nested field names: customer.firstName
• Array values: customer.address[2].city
• Positional field access: customer.address[2][0]
• Positional field access: [1]
• String arrays (for field names with spaces): customer.address[2]["zip code"]
• String arrays (using single quotes): customer.address[2]['zip code']
• Quoted field names (for field names with spaces or symbols): 'Company Flag (Y/N)'
• Quoted nested field names (for field names with spaces or symbols): customer."Company Flag (Y/N)"
• Quoted array values (for field names with spaces or symbols): `Company Address`[0]

Identifiers in field expressions may start with letters, underscores (_), at symbols (@), or dollar signs ($) and contain letters, numbers, underscores, at symbols, and dollar signs. You will need to quote field expressions that contain other symbols and spaces if they should be treated as part of the field name. For example, if your field name contains a period, you will need to quote it ("Package Lbs.").

Quoting:When quoting fields, you can use double quotes ("), single quotes ('), or grave accent (`).

A note of caution: FieldPath can also represent the location of values in array fields. For example, city[2] or customer.address[0].city[2] could match the third city in an array field. Some methods and operations expecting a field will throw an exception (or return false) if the supplied FieldPath matches an array value and not a field.

See Also:

parse(String), name(String), index(int), Record.getField(FieldPath), Record.getField(FieldPath, boolean, boolean), Record.getValue(FieldPath), Record.getValue(FieldPath, boolean), Record.getValue(FieldPath, boolean, boolean), Record.containsField(FieldPath), Record.contains(FieldPath)

Constructor Summary

Constructors

Constructor and Description
FieldPath()

Method Summary

Modifier and Type	Method and Description
boolean	contains(Record record) Deprecated.
boolean	containsField(Record record)
boolean	containsNonNullField(Record record)
boolean	containsNonNullValue(Record record)
boolean	containsValue(Record record)
boolean	equals(Object o)
static FieldPath	fromName(String fieldName) Converts a single field name into a FieldPath.
Field	getField(Record record, boolean create, boolean throwException)
String	getSimpleName() Returns the name (or number/index) of the last segment in this path as a string.
SingleValue	getSingleValue(Record record, boolean create, boolean throwException)
Object	getValue(Record record, boolean create, boolean throwException)
ValueNode<?>	getValueNode(Record record, boolean create, boolean throwException)
int	hashCode()
FieldPath	index(int index)
boolean	isTabular() Indicates if this path matches against a flat record (i.e.
FieldPath	name(String name) Appends a new field name segment to this field path.
static FieldPath	parse(String fieldPathExpression) Converts a field path expression into a FieldPath object.
String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

FieldPath

public FieldPath()

Method Detail

parse

public static FieldPath parse(String fieldPathExpression)

Converts a field path expression into a FieldPath object. Expressions can be:

• Single field names: firstName
• Nested field names: customer.firstName
• Array values: customer.address[2].city
• Positional field access: customer.address[2][0]
• Positional field access: [1]
• String arrays (for field names with spaces): customer.address[2]["zip code"]
• String arrays (using single quotes): customer.address[2]['zip code']
• Quoted field names (for field names with spaces or symbols): 'Company Flag (Y/N)'
• Quoted nested field names (for field names with spaces or symbols): customer."Company Flag (Y/N)"
• Quoted array values (for field names with spaces or symbols): `Company Address`[0]

Identifiers in field expressions may start with letters, underscores (_), at symbols (@), or dollar signs ($) and contain letters, numbers, underscores, at symbols, and dollar signs. You will need to quote field expressions that contain other symbols and spaces if they should be treated as part of the field name. For example, if your field name contains a period, you will need to quote it ("Package Lbs.").

Quoting:When quoting fields, you can use double quotes ("), single quotes ('), or grave accent (`).

fromName

public static FieldPath fromName(String fieldName)

Converts a single field name into a FieldPath. This method does no parsing and treats all characters as part of the field name.

name

public FieldPath name(String name)

Appends a new field name segment to this field path.

index

public FieldPath index(int index)

isTabular

public boolean isTabular()

Indicates if this path matches against a flat record (i.e. no nested records or array fields).

getField

public Field getField(Record record,
                      boolean create,
                      boolean throwException)

getSingleValue

public SingleValue getSingleValue(Record record,
                                  boolean create,
                                  boolean throwException)

getValueNode

public ValueNode<?> getValueNode(Record record,
                                 boolean create,
                                 boolean throwException)

getValue

public Object getValue(Record record,
                       boolean create,
                       boolean throwException)

containsField

public boolean containsField(Record record)

containsNonNullField

public boolean containsNonNullField(Record record)

contains

@Deprecated
public boolean contains(Record record)

Deprecated.

Use containsValue(Record) instead.

containsValue

public boolean containsValue(Record record)

containsNonNullValue

public boolean containsNonNullValue(Record record)

getSimpleName

public String getSimpleName()

Returns the name (or number/index) of the last segment in this path as a string.

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(Object o)

Overrides:

equals in class Object

toString

public String toString()

Overrides:

toString in class Object