uk.ac.sheffield.vtts.ground

Class AbstractFactory

java.lang.Object

uk.ac.sheffield.vtts.ground.AbstractFactory

All Implemented Interfaces:

Factory

Direct Known Subclasses:

JavaFactory, ModelFactory

public abstract class AbstractFactory
extends java.lang.Object
implements Factory

AbstractFactory is the common ancestor of ModelFactory and JavaFactory. AbstractFactory provides operations for creating instances of basic types and generic List, Set, Map and Pair types. It provides hooks for creating instances of further uninterpreted types. Creates instances of all the predefined basic Java types, which have identical names in the modelling language. For the generic types, maps the type List to ArrayList, Set to HashSet, Map to HashMap and Pair to SimpleEntry.

The strongly-typed create() method calls the main createObject() factory method. This first checks whether the supplied type is generic; if so, it dispatches to the appropriate method to create a List, Set, Map or Pair object. Otherwise, it expects to create a simple object. If the type is not a predefined type, creates an instance of an external type.

Normally the value and type are supplied as String values, either using the model language syntax, or Java syntax. The type String is checked for correct generic syntax. If the value is null or empty, will create a default instance of the given type. For List, Set and Map types, this is an empty instance. For other types, this is the usual Java default instance (zero, false, etc). The methods for creating List, Set and Map types expect the value to be the usual printable representation of that collection type; however, if a single element value is provided, a singleton collection will be created. The wildcard "?" represents the default singleton value.

Version:

Broker@Cloud 1.0

Author:

Anthony J H Simons

Constructor Summary

Constructors

Constructor and Description
AbstractFactory()

Method Summary

Methods

Modifier and Type	Method and Description
<T> T	create(java.lang.String value, java.lang.String type) Creates a strongly-typed instance of any kind of Java Object with the given printed representation and Java type.
protected java.lang.Object	createDefaultObject(java.lang.String type) Creates a default object of a simple type.
protected abstract java.lang.Object	createExternalObject(java.lang.String value, java.lang.String type) Creates an instance of an uninterpreted external type, with the given value.
protected java.util.List<java.lang.Object>	createListObject(java.lang.String value, java.util.List<java.lang.String> params) Creates a generic List of the given element type, having the given value.
protected java.util.Map<java.lang.Object,java.lang.Object>	createMapObject(java.lang.String value, java.util.List<java.lang.String> params) Creates a generic Map object of the given parametric type, with the given value.
protected java.util.Map.Entry<java.lang.Object,java.lang.Object>	createPairObject(java.lang.String value, java.util.List<java.lang.String> params) Creates a generic Pair object of the given parametric type, with the given value.
protected java.util.Set<java.lang.Object>	createSetObject(java.lang.String value, java.util.List<java.lang.String> params) Creates a generic Set of the given element type, having the given value.
protected java.lang.Object	createSimpleObject(java.lang.String value, java.lang.String type) Creates an object of a simple type, having the given value.
protected void	error(java.lang.String message) Reports an IllegalArgumentException during object creation.
protected java.lang.String	makeEntityId(java.lang.String type) Try to synthesise an Entity ID in cases where these are manufactured.
protected int	safeIndexOf(java.lang.String string, char separator, int startIndex) Finds the first index of a separator in a String, starting from a given index, while respecting bracketed structures.
protected java.util.List<java.lang.String>	safeSplit(java.lang.String string, java.lang.String regex) Safe search routine to split a value-string containing recursively embedded value-strings.

Methods inherited from class java.lang.Object

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

Methods inherited from interface uk.ac.sheffield.vtts.ground.Factory

createObject

Constructor Detail

AbstractFactory

public AbstractFactory()

Method Detail

error

protected void error(java.lang.String message)
              throws java.lang.IllegalArgumentException

Reports an IllegalArgumentException during object creation. Raised if either the type string or value string is badly formed. This is a kind of RutimeException.

Parameters:

message - the error message.

Throws:

java.lang.IllegalArgumentException - always.

safeIndexOf

protected int safeIndexOf(java.lang.String string,
              char separator,
              int startIndex)

Finds the first index of a separator in a String, starting from a given index, while respecting bracketed structures. Works like indexOf(), except that it skips over bracketed structures that may also contain the separator character and returns the index of the first separator found at the top level. Counts all kinds of brackets, including angle, square, brace and round brackets.

Parameters:

string - the String to search.

separator - the separator character.

startIndex - the index at which to start searching.

Returns:

the index of the separator, or -1 if it is not found.

safeSplit

protected java.util.List<java.lang.String> safeSplit(java.lang.String string,
                                         java.lang.String regex)

Safe search routine to split a value-string containing recursively embedded value-strings. It works like split(), except that it also counts the numbers of opening and closing square brackets and braces, to make sure that the split divides up the topmost values, rather than embedded values. The given value-string must be supplied without any surrounding brackets or braces.

Parameters:

string - the multi-part value, as a String, not bracketed.

regex - the separator pattern.

Returns:

a list of separated strings.

makeEntityId

protected java.lang.String makeEntityId(java.lang.String type)

Try to synthesise an Entity ID in cases where these are manufactured. The default ID is the first three characters of the Entity type, in lower case, followed by the digit "1". This is expected to correspond to the first legitimate Entity ID in the model.

Parameters:

type - the type name of the Entity.

Returns:

a synthetic ID string.

create

public <T> T create(java.lang.String value,
           java.lang.String type)

Creates a strongly-typed instance of any kind of Java Object with the given printed representation and Java type. Performs an unchecked type cast on the result of createObject(). Provided for convenience.

Specified by:

create in interface Factory

Type Parameters:

T - the returned object type.

Parameters:

value - the value, as a String.

type - the Java type, as a String.

Returns:

a new instance of the type.

createDefaultObject

protected java.lang.Object createDefaultObject(java.lang.String type)

Creates a default object of a simple type. Creates a default instance of the main types: String, Integer, Double, Boolean, Character, Long, Float, Short and Byte. If the type is not one of these, creates an instance of a user-defined type.

Parameters:

type - the type as a String.

Returns:

a new instance of the type.

createSimpleObject

protected java.lang.Object createSimpleObject(java.lang.String value,
                                  java.lang.String type)

Creates an object of a simple type, having the given value. Creates an instance of the main simple types: String, Integer, Double, Boolean, Character, Long, Float, Short and Byte. If the type is not one of these, creates an instance of a user-defined type.

Parameters:

value - the value, as a String.

type - the type, as a String.

Returns:

a new instance.

createExternalObject

protected abstract java.lang.Object createExternalObject(java.lang.String value,
                                    java.lang.String type)

Creates an instance of an uninterpreted external type, with the given value. External types are user-defined types that are uninterpreted in the modelling language, but could correspond to program types used by the Service-Under-Test. This method is abstract and must be implemented in descendant factories.

Parameters:

value - an identifier String.

type - an external type, as a String.

Returns:

a suitable model instance or program instance.

createListObject

protected java.util.List<java.lang.Object> createListObject(java.lang.String value,
                                                java.util.List<java.lang.String> params)

Creates a generic List of the given element type, having the given value. The value may be null or empty, in which case an empty List is returned. Otherwise, the value must be the printed representation of a List, surrounded by square brackets, with comma-separated values as the elements; or a singleton value.

Parameters:

value - the list-value, as a String.

params - the generic List type parameters.

Returns:

a new List of the given generic type.

createSetObject

protected java.util.Set<java.lang.Object> createSetObject(java.lang.String value,
                                              java.util.List<java.lang.String> params)

Creates a generic Set of the given element type, having the given value. The value may be null or empty, in which case an empty Set is returned. Otherwise, the value must be the printed representation of a Set, surrounded by square brackets, with comma-separated values as the elements; or a singleton value.

Parameters:

value - the set-value, as a String.

params - the generic Set type parameters.

Returns:

a new Set of the given generic type.

createMapObject

protected java.util.Map<java.lang.Object,java.lang.Object> createMapObject(java.lang.String value,
                                                               java.util.List<java.lang.String> params)

Creates a generic Map object of the given parametric type, with the given value. The value may be null or empty, in which case an empty Map is returned. Otherwise, the value must be the printed representation of a Map, surrounded by braces, with comma-separated values as the pair-elements. Each pair-element must separate the first and second values with "=".

Parameters:

value - the map-value, as a String.

params - the generic Map type parameters.

Returns:

a new Map of the given generic type.

createPairObject

protected java.util.Map.Entry<java.lang.Object,java.lang.Object> createPairObject(java.lang.String value,
                                                                      java.util.List<java.lang.String> params)

Creates a generic Pair object of the given parametric type, with the given value. The value may be null or empty, in which case a default Entry is created, wrapping two default objects of the first and second types. The value may be a key of the first type, in which case an Entry is created with that key and a default object of the second type. Otherwise, the value must be the printed representation of a Pair, with the first and second components separated by "=".

Parameters:

value - the pair-value, as a String.

params - the generic Entry type parameters.

Returns:

a new Entry of the given generic type.