Class FieldScanner

java.lang.Object

java.util.AbstractCollection<Contact>

java.util.AbstractList<Contact>

java.util.ArrayList<Contact>

org.simpleframework.xml.core.ContactList

org.simpleframework.xml.core.FieldScanner

All Implemented Interfaces:

Serializable, Cloneable, Iterable<Contact>, Collection<Contact>, List<Contact>, RandomAccess, SequencedCollection<Contact>

class FieldScanner
extends ContactList

The FieldScanner object is used to scan an class for fields marked with an XML annotation. All fields that contain an XML annotation are added as Contact objects to the list of contacts for the class. This scans the object by checking the class hierarchy, this allows a subclass to override a super class annotated field, although this should be used rarely.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
private static class	FieldScanner.FieldKey	The FieldKey object is used to create a key that can store a contact using a field without using the methods of hashCode and equals on the field directly, as these can perform poorly on certain platforms.

Field Summary

Fields

Modifier and Type	Field	Description
private final ContactMap	done	This is used to determine which fields have been scanned.
private final AnnotationFactory	factory	This is used to create the synthetic annotations for fields.
private final Support	support	This object contains various support functions for the class.

Fields inherited from class AbstractList

modCount

Constructor Summary

Constructors

Constructor	Description
FieldScanner(Detail detail, Support support)	Constructor for the FieldScanner object.

Method Summary

Modifier and Type	Method	Description
private void	build()	This is used to build a list of valid contacts for this scanner.
private void	extend(Class base, DefaultType access)	This method is used to extend the provided class.
private void	extract(Detail detail)	This is used to scan the declared fields within the specified class.
private void	extract(Detail detail, DefaultType access)	This is used to scan all the fields of the class in order to determine if it should have a default annotation.
private void	insert(Object key, Contact contact)	This is used to insert a contact to this contact list.
private boolean	isStatic(Field field)	This is used to determine if a field is static.
private boolean	isText(Contact contact)	This is used to determine if the Text annotation has been declared on the field.
private boolean	isTransient(Field field)	This is used to determine if a field is transient.
private void	process(Field field, Annotation label, Annotation[] list)	This method is used to process the field an annotation given.
private void	process(Field field, Class type, Annotation[] list)	This method is used to process the field an annotation given.
private void	remove(Field field, Annotation label)	This is used to remove a field from the map of processed fields.
private void	scan(Field field, Annotation label, Annotation[] list)	This reflectively checks the annotation to determine the type of annotation it represents.
private void	scan(Detail detail)	This method is used to scan the class hierarchy for each class in order to extract fields that contain XML annotations.

Methods inherited from class ArrayList

add, add, addAll, addAll, addFirst, addLast, clear, clone, contains, ensureCapacity, equals, forEach, get, getFirst, getLast, hashCode, indexOf, isEmpty, iterator, lastIndexOf, listIterator, listIterator, remove, remove, removeAll, removeFirst, removeIf, removeLast, removeRange, replaceAll, retainAll, set, size, sort, spliterator, subList, toArray, toArray, trimToSize

Methods inherited from class AbstractCollection

containsAll, toString

Methods inherited from class Object

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

Methods inherited from interface Collection

parallelStream, stream, toArray

Methods inherited from interface List

containsAll, reversed

Field Details

factory

private final AnnotationFactory factory

This is used to create the synthetic annotations for fields.

done

private final ContactMap done

This is used to determine which fields have been scanned.

support

private final Support support

This object contains various support functions for the class.

Constructor Details

FieldScanner

public FieldScanner(Detail detail,
 Support support)
             throws Exception

Constructor for the FieldScanner object. This is used to perform a scan on the specified class in order to find all fields that are labeled with an XML annotation.

Parameters:

detail - this contains the details for the class scanned

support - this contains various support functions

Throws:

Exception

Method Details

scan

private void scan(Detail detail)
           throws Exception

This method is used to scan the class hierarchy for each class in order to extract fields that contain XML annotations. If the field is annotated it is converted to a contact so that it can be used during serialization and deserialization.

Parameters:

detail - this contains the details for the class scanned

Throws:

Exception

extend

private void extend(Class base,
 DefaultType access)
             throws Exception

This method is used to extend the provided class. Extending a class in this way basically means that the fields that have been scanned in the specific class will be added to this. Doing this improves the performance of classes within a hierarchy.

Parameters:

base - the class to inherit scanned fields from

access - this is the access type used for the super type

Throws:

Exception

extract

private void extract(Detail detail)

This is used to scan the declared fields within the specified class. Each method will be check to determine if it contains an XML element and can be used as a Contact for an entity within the object.

Parameters:

detail - this is one of the super classes for the object

extract

private void extract(Detail detail,
 DefaultType access)
              throws Exception

This is used to scan all the fields of the class in order to determine if it should have a default annotation. If the field should have a default XML annotation then it is added to the list of contacts to be used to form the class schema.

Parameters:

detail - this is the detail to have its fields scanned

access - this is the default access type for the class

Throws:

Exception

scan

private void scan(Field field,
 Annotation label,
 Annotation[] list)

This reflectively checks the annotation to determine the type of annotation it represents. If it represents an XML schema annotation it is used to create a Contact which can be used to represent the field within the source object.

Parameters:

field - the field that the annotation comes from

label - the annotation used to model the XML schema

list - this is the list of annotations on the field

process

private void process(Field field,
 Class type,
 Annotation[] list)
              throws Exception

This method is used to process the field an annotation given. This will check to determine if the field is accessible, if it is not accessible then it is made accessible so that private member fields can be used during the serialization process.

Parameters:

field - this is the field to be added as a contact

type - this is the type to acquire the annotation

list - this is the list of annotations on the field

Throws:

Exception

process

private void process(Field field,
 Annotation label,
 Annotation[] list)

This method is used to process the field an annotation given. This will check to determine if the field is accessible, if it is not accessible then it is made accessible so that private member fields can be used during the serialization process.

Parameters:

field - this is the field to be added as a contact

label - this is the XML annotation used by the field

list - this is the list of annotations on the field

insert

private void insert(Object key,
 Contact contact)

This is used to insert a contact to this contact list. Here if a Text annotation is declared on a field that already has an annotation then the other annotation is given the priority, this is to so text can be processes separately.

Parameters:

key - this is the key that uniquely identifies the field

contact - this is the contact that is to be inserted

isText

private boolean isText(Contact contact)

This is used to determine if the Text annotation has been declared on the field. If this annotation is used then this will return true, otherwise this returns false.

Parameters:

contact - the contact to check for the text annotation

Returns:

true if the text annotation was declared on the field

remove

private void remove(Field field,
 Annotation label)

This is used to remove a field from the map of processed fields. A field is removed with the Transient annotation is used to indicate that it should not be processed by the scanner. This is required when default types are used.

Parameters:

field - this is the field to be removed from the map

label - this is the label associated with the field

build

private void build()

This is used to build a list of valid contacts for this scanner. Valid contacts are fields that are either defaulted or those that have an explicit XML annotation. Any field that has been marked as transient will not be considered as valid.

isStatic

private boolean isStatic(Field field)

This is used to determine if a field is static. If a field is static it should not be considered as a default field. This ensures the default annotation does not pick up static finals.

Parameters:

field - this is the field to determine if it is static

Returns:

true if the field is static, false otherwise

isTransient

private boolean isTransient(Field field)

This is used to determine if a field is transient. For default fields that are processed no transient field should be considered. This ensures that the serialization of the object behaves in the same manner as with Java Object Serialization.

Parameters:

field - this is the field to check for transience

Returns:

this returns true if the field is a transient one