Module io.jenetics.xml

Package io.jenetics.xml.stream

Class Reader<T>

java.lang.Object

io.jenetics.xml.stream.Reader<T>

public abstract class Reader<T>
extends Object

XML reader class, used for reading objects in XML format. XML

 
 <int-chromosome length="3">
     <min>-2147483648</min>
     <max>2147483647</max>
     <alleles>
         <allele>-1878762439</allele>
         <allele>-957346595</allele>
         <allele>-88668137</allele>
     </alleles>
 </int-chromosome>
 

Reader definition

final Reader<IntegerChromosome> reader = elem( (Object[] v) -> { final int length = (int)v[0]; final int min = (int)v[1]; final int max = (int)v[2]; final List<Integer> alleles = (List<Integer>)v[3]; assert alleles.size() == length; return IntegerChromosome.of( alleles.stream() .map(value -> IntegerGene.of(value, min, max) .toArray(IntegerGene[]::new) ); }, "int-chromosome", attr("length").map(Integer::parseInt), elem("min", text().map(Integer::parseInt)), elem("max", text().map(Integer::parseInt)), elem("alleles", elems(elem("allele", text().map(Integer::parseInt))) ) );

Since:

3.9

Version:

3.9

Method Summary

Modifier and Type	Method	Description
static Reader<String>	attr(String name)	Return a Reader for reading an attribute of an element.
static <T> Reader<T>	elem(String name, Reader<? extends T> reader)	Return a Reader which reads the value from the child elements of the given parent element name.
static <T> Reader<T>	elem(Function<Object[],T> generator, String name, Reader<?>... children)	Return a Reader for reading an object of type T from the XML element with the given name.
static <T> Reader<List<T>>	elems(Reader<? extends T> reader)	Return a Reader which collects the elements, read by the given child reader, and returns it as list of these elements.
<B> Reader<B>	map(Function<? super T,? extends B> mapper)	Create a new reader for the new mapped type B.
abstract T	read(XMLStreamReader xml)	Read the given type from the underlying XML stream reader.
static Reader<String>	text()	Return a Reader for reading the text of an element.
String	toString()

Methods inherited from class java.lang.Object

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

Method Details

read

public abstract T read(XMLStreamReader xml)
                throws XMLStreamException

Read the given type from the underlying XML stream reader.

try (AutoCloseableXMLStreamReader xml = XML.reader(in)) { // Move XML stream to first element. xml.next(); return reader.read(xml); }

Parameters:

xml - the underlying XML stream reader

Returns:

the data read from the XML stream, maybe null

Throws:

XMLStreamException - if an error occurs while reading the value

NullPointerException - if the given xml stream reader is null

map

public <B> Reader<B> map(Function<? super T,? extends B> mapper)

Create a new reader for the new mapped type B.

Type Parameters:

B - the target type of the new reader

Parameters:

mapper - the mapper function

Returns:

a new reader

Throws:

NullPointerException - if the given mapper function is null

toString

public String toString()

Overrides:

toString in class Object

attr

public static Reader<String> attr(String name)

Return a Reader for reading an attribute of an element.

XML

 <element length="3"/>

Reader definition

final Reader<Integer> reader = elem( v -> (Integer)v[0], "element", attr("length").map(Integer::parseInt) );

Parameters:

name - the attribute name

Returns:

an attribute reader

Throws:

NullPointerException - if the given name is null

text

public static Reader<String> text()

Return a Reader for reading the text of an element.

XML

 <element>1234<element>

Reader definition

final Reader<Integer> reader = elem( v -> (Integer)v[0], "element", text().map(Integer::parseInt) );

Returns:

an element text reader

elem

public static <T> Reader<T> elem(Function<Object[],T> generator,
 String name,
 Reader<?>... children)

Return a Reader for reading an object of type T from the XML element with the given name.

XML

 <property name="size">1234<property>

Reader definition

final Reader<Property> reader = elem( v -> { final String name = (String)v[0]; final Integer value = (Integer)v[1]; return Property.of(name, value); }, "property", attr("name"), text().map(Integer::parseInt) );

Type Parameters:

T - the reader result type

Parameters:

generator - the generator function, which build the result object from the given parameter array

name - the name of the root (sub-tree) element

children - the child element reader, which creates the values forwarded to the generator function

Returns:

a node reader

Throws:

NullPointerException - if one of the given arguments is null

IllegalArgumentException - if the given child readers contains more than one text reader

elem

public static <T> Reader<T> elem(String name,
 Reader<? extends T> reader)

Return a Reader which reads the value from the child elements of the given parent element name.

XML

 <min><property name="size">1234<property></min>

Reader definition

final Reader<Property> reader = elem("min", elem( v -> { final String name = (String)v[0]; final Integer value = (Integer)v[1]; return Property.of(name, value); }, "property", attr("name"), text().map(Integer::parseInt) ) );

Type Parameters:

T - the result type

Parameters:

name - the parent element name

reader - the child elements reader

Returns:

a node reader

Throws:

NullPointerException - if one of the given arguments is null

elems

public static <T> Reader<List<T>> elems(Reader<? extends T> reader)

Return a Reader which collects the elements, read by the given child reader, and returns it as list of these elements.

XML

 
 <properties length="3">
     <property>-1878762439</property>
     <property>-957346595</property>
     <property>-88668137</property>
 </properties>
 

Reader definition

Reader<List<Integer>> reader = elem( v -> (List<Integer>)v[0], "properties", elems(elem("property", text().map(Integer::parseInt))) );

Type Parameters:

T - the element type

Parameters:

reader - the child element reader

Returns:

a list reader