us.codecraft.webmagic.model.annotation

Annotation Type ExtractBy

@Retention(value=RUNTIME)
 @Target(value={FIELD,TYPE})
public @interface ExtractBy

Define the extractor for field or class.

Since:

0.2.0

Author:

code4crafter@gmail.com

Required Element Summary

Required Elements

Modifier and Type	Required Element and Description
String	value Extractor expression, support XPath, CSS Selector and regex.

Optional Element Summary

Optional Elements

Modifier and Type	Optional Element and Description
boolean	multi Deprecated. since 0.4.2
boolean	notNull Define whether the field can be null. If set to 'true' and the extractor get no result, the entire class will be discarded.
ExtractBy.Source	source The source for extracting.
ExtractBy.Type	type Extractor type, support XPath, CSS Selector and regex.

Element Detail

value

public abstract String value

Extractor expression, support XPath, CSS Selector and regex.

Returns:

extractor expression

type

public abstract ExtractBy.Type type

Extractor type, support XPath, CSS Selector and regex.

Returns:

extractor type

Default:

us.codecraft.webmagic.model.annotation.ExtractBy.Type.XPath

notNull

public abstract boolean notNull

Define whether the field can be null.
If set to 'true' and the extractor get no result, the entire class will be discarded.

Returns:

whether the field can be null

Default:

false

source

public abstract ExtractBy.Source source

The source for extracting.
It works only if you already added 'ExtractBy' to Class.

Returns:

the source for extracting

Default:

us.codecraft.webmagic.model.annotation.ExtractBy.Source.SelectedHtml

multi

public abstract boolean multi

Deprecated. since 0.4.2

Define whether the extractor return more than one result. When set to 'true', the extractor return a list of string (so you should define the field as List).
Deprecated since 0.4.2. This option is determined automatically by the class of field.

Returns:

whether the extractor return more than one result

Default:

false