io.github.prolobjectlink.prolog

Class AbstractEngine

java.lang.Object

io.github.prolobjectlink.prolog.AbstractEngine

All Implemented Interfaces:

PrologEngine, Iterable<PrologClause>

public abstract class AbstractEngine
extends Object
implements PrologEngine

Partial implementation of PrologEngine.

Since:

1.0

Author:

Jose Zalacain

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected class	AbstractEngine.PrologProgramIterator

Field Summary

Fields

Modifier and Type	Field and Description
protected PrologProvider	provider

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	AbstractEngine(PrologProvider provider)

Method Summary

Modifier and Type	Method and Description
boolean	contains(PrologTerm goal) Check if the given goal array have solution using the resolution engine mechanism.
boolean	contains(PrologTerm goal, PrologTerm... goals) Check if the given goal array have solution using the resolution engine mechanism.
boolean	contains(String goal) Parse the string creating internal prolog clause and returning true if the given goal have solution using the resolution engine mechanism.
Set<PrologIndicator>	currentPredicates() Predicate set defined in the wrapped prolog engine.
boolean	equals(Object object)
protected <K> K	fromTerm(PrologTerm term, Class<K> to)
protected <K> K	fromTerm(PrologTerm head, PrologTerm[] body, Class<K> to)
PrologLogger	getLogger() Get the prolog system logger instance to report any errors or exceptions
String	getOSArch() Return the host operating system architecture.
String	getOSName() Return the host operating system name.
String	getOSVersion() Return the host operating system version.
Set<PrologClause>	getProgramClauses() Make and return a copy of the clause set present in the current engine.
Map<String,List<PrologClause>>	getProgramMap() Make and return a copy of the clause map present in the current engine.
PrologProvider	getProvider() Get a Prolog provider instance hold in the current engine.
int	hashCode()
boolean	isProgramEmpty() Check if the program in main memory is empty returning true if the clause number in the program is 0 and false in otherwise.
Map<String,PrologTerm>	match(PrologTerm t1, PrologTerm t2) Match to other term returning list of substitutions.
io.github.prolobjectlink.prolog.DefaultClauseBuilder	newClauseBuilder() Create a new clause builder instance to build prolog clauses programmatically.
io.github.prolobjectlink.prolog.DefaultQueryBuilder	newQueryBuilder() Create a new query builder instance to build prolog goal programmatically.
void	persist(Writer writer) Write the prolog clauses in program present in the current engine using the given driver.
List<Map<String,PrologTerm>>	queryAll(PrologTerm goal)
List<Map<String,PrologTerm>>	queryAll(PrologTerm goal, PrologTerm... goals) Create a new prolog query and return the list of prolog terms that conform the solution set for the current query.
List<Map<String,PrologTerm>>	queryAll(String goal) Create a new prolog query and return the list of prolog terms that conform the solution set for the current query.
List<Map<String,PrologTerm>>	queryN(int n, PrologTerm term)
List<Map<String,PrologTerm>>	queryN(int n, PrologTerm term, PrologTerm... terms) Create a new prolog query and return the list of (N) prolog terms that conform the solution set for the current query.
List<Map<String,PrologTerm>>	queryN(int n, String goal) Create a new prolog query and return the list of (N) prolog terms that conform the solution set for the current query.
Map<String,PrologTerm>	queryOne(PrologTerm goal)
Map<String,PrologTerm>	queryOne(PrologTerm goal, PrologTerm... goals) Create a new prolog query and return the prolog terms that conform the solution set for the current query.
Map<String,PrologTerm>	queryOne(String goal) Create a new prolog query and return the prolog terms that conform the solution set for the current query.
protected String	removeQuoted(String functor)
boolean	runOnLinux() Check if the host operating system name refer to Linux OS.
boolean	runOnOSX() Check if the host operating system name refer to OsX.
boolean	runOnWindows() Check if the host operating system name refer to Windows OS.
String	toString()
protected <K extends PrologTerm> K	toTerm(Object o, Class<K> from)
protected <K extends PrologTerm,V> Map<String,PrologTerm>[]	toTermMapArray(Map<String,V>[] map, Class<K> from)
boolean	unify(PrologTerm t1, PrologTerm t2) Check that two terms (x and y) unify.

Methods inherited from class java.lang.Object

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

Methods inherited from interface io.github.prolobjectlink.prolog.PrologEngine

abolish, asserta, asserta, asserta, assertz, assertz, assertz, clause, clause, clause, consult, consult, currentOperator, currentOperators, currentPredicate, dispose, getBuiltIns, getLicense, getName, getPredicates, getProgram, getProgramSize, getVendor, getVersion, include, include, operator, persist, query, query, query, query, retract, retract, retract, verify

Methods inherited from interface java.lang.Iterable

forEach, iterator, spliterator

Field Detail

provider

protected final PrologProvider provider

Constructor Detail

AbstractEngine

protected AbstractEngine(PrologProvider provider)

Method Detail

getProvider

public final PrologProvider getProvider()

Description copied from interface: PrologEngine

Get a Prolog provider instance hold in the current engine.

Specified by:

getProvider in interface PrologEngine

Returns:

a Prolog provider instance.

persist

public final void persist(Writer writer)

Description copied from interface: PrologEngine

Write the prolog clauses in program present in the current engine using the given driver.

Specified by:

persist in interface PrologEngine

Parameters:

writer - writer for write prolog clauses in the program.

unify

public final boolean unify(PrologTerm t1,
                           PrologTerm t2)

Description copied from interface: PrologEngine

Check that two terms (x and y) unify. Prolog unification algorithm is based on three principals rules:

• If x and y are atomics constants then x and y unify only if they are same object.
• If x is a variable and y is anything then they unify and x is instantiated to y. Conversely, if y is a variable then this is instantiated to x.
• If x and y are structured terms then unify only if they match (equals funtor and arity) and all their correspondents arguments unify.

Specified by:

unify in interface PrologEngine

Parameters:

t1 - the term to unify.

t2 - the term to unify.

Returns:

true if the specified term unify whit the current term, false otherwise.

match

public Map<String,PrologTerm> match(PrologTerm t1,
                                    PrologTerm t2)

Description copied from interface: PrologEngine

Match to other term returning list of substitutions. Used to compute the most general unifier.

Specified by:

match in interface PrologEngine

Parameters:

t1 - the term to unify.

t2 - the term to unify.

Returns:

true if the specified term unify whit the current term, false otherwise.

contains

public final boolean contains(String goal)

Description copied from interface: PrologEngine

Parse the string creating internal prolog clause and returning true if the given goal have solution using the resolution engine mechanism. If wrapped engine not support a dedicated method then contains can be defined like query(goal).hasSolution()

Specified by:

contains in interface PrologEngine

Parameters:

goal - goal to be queried

Returns:

true if the given goal has solution

contains

public final boolean contains(PrologTerm goal)

Description copied from interface: PrologEngine

Check if the given goal array have solution using the resolution engine mechanism. If wrapped engine not support a dedicated method then contains can be defined like: query(goal).hasSolution()

Specified by:

contains in interface PrologEngine

Parameters:

goal - goal to be checked

Returns:

true if the given goal has solution

contains

public final boolean contains(PrologTerm goal,
                              PrologTerm... goals)

Description copied from interface: PrologEngine

Check if the given goal array have solution using the resolution engine mechanism. If wrapped engine not support a dedicated method then contains can be defined like: query(goal).hasSolution()

Specified by:

contains in interface PrologEngine

Parameters:

goal - goal to be checked

goals - goals array with the rest of conjunctive goals term (can be empty)

Returns:

true if the given goal has solution

queryOne

public final Map<String,PrologTerm> queryOne(String goal)

Description copied from interface: PrologEngine

Create a new prolog query and return the prolog terms that conform the solution set for the current query. The solution set is a prolog terms map and every map entry is a pair variable name and variable instance value for the variables not anonymous involved in the query.

 List<Map<String, PrologTerm>> m = engine.queryAll("parent(X, Y)");
 

Specified by:

queryOne in interface PrologEngine

Parameters:

goal - string query with prolog format.

Returns:

variable name - variable instance (key - value) map that conform the solution set for the current query.

queryOne

public final Map<String,PrologTerm> queryOne(PrologTerm goal)

Specified by:

queryOne in interface PrologEngine

Returns:

queryOne

public final Map<String,PrologTerm> queryOne(PrologTerm goal,
                                             PrologTerm... goals)

Description copied from interface: PrologEngine

Create a new prolog query and return the prolog terms that conform the solution set for the current query. The solution set is a prolog terms map and every map entry is a pair variable name and variable instance value for the variables not anonymous involved in the query.

 PrologVariable x = provider.newVariable("X", 0);
 PrologVariable y = provider.newVariable("Y", 1);
 Map<String, PrologTerm> m = engine.queryOne(provider.newStructure("parent", x, y));
 

Specified by:

queryOne in interface PrologEngine

Parameters:

goal - prolog term to be query

goals - prolog term array to be query.

Returns:

variable name - variable instance (key - value) map that conform the solution set for the current query.

queryN

public final List<Map<String,PrologTerm>> queryN(int n,
                                                 String goal)

Description copied from interface: PrologEngine

Create a new prolog query and return the list of (N) prolog terms that conform the solution set for the current query. Each list item is a prolog terms map and every map entry is a pair variable name and variable instance value for the variables not anonymous involved in the query.

Specified by:

queryN in interface PrologEngine

Parameters:

n - query result instance number

goal - string with prolog syntax to be query

Returns:

the list of prolog terms that conform the solution set for the current query.

queryN

public final List<Map<String,PrologTerm>> queryN(int n,
                                                 PrologTerm term)

Specified by:

queryN in interface PrologEngine

Returns:

queryN

public final List<Map<String,PrologTerm>> queryN(int n,
                                                 PrologTerm term,
                                                 PrologTerm... terms)

Description copied from interface: PrologEngine

Create a new prolog query and return the list of (N) prolog terms that conform the solution set for the current query. Each list item is a prolog terms map and every map entry is a pair variable name and variable instance value for the variables not anonymous involved in the query.

 PrologVariable x = provider.newVariable("X", 0);
 PrologVariable y = provider.newVariable("Y", 1);
 List<Map<String, PrologTerm>> m = engine.queryN(5, provider.newStructure("parent", x, y));
 

Specified by:

queryN in interface PrologEngine

Parameters:

n - query result instance number

term - prolog term to be query

terms - prolog term array to be query.

Returns:

the list of prolog terms that conform the solution set for the current query.

queryAll

public final List<Map<String,PrologTerm>> queryAll(String goal)

Description copied from interface: PrologEngine

Create a new prolog query and return the list of prolog terms that conform the solution set for the current query. Each list item is a prolog terms map and every map entry is a pair variable name and variable instance value for the variables not anonymous involved in the query.

Specified by:

queryAll in interface PrologEngine

Parameters:

goal - string with prolog syntax to be query

Returns:

the list of prolog terms that conform the solution set for the current query.

queryAll

public final List<Map<String,PrologTerm>> queryAll(PrologTerm goal)

Specified by:

queryAll in interface PrologEngine

Returns:

queryAll

public final List<Map<String,PrologTerm>> queryAll(PrologTerm goal,
                                                   PrologTerm... goals)

Description copied from interface: PrologEngine

Create a new prolog query and return the list of prolog terms that conform the solution set for the current query. Each list item is a prolog terms map and every map entry is a pair variable name and variable instance value for the variables not anonymous involved in the query.

 PrologVariable x = provider.newVariable("X", 0);
 PrologVariable y = provider.newVariable("Y", 1);
 List<Map<String, PrologTerm>> m = engine.queryAll(provider.newStructure("parent", x, y));
 

Specified by:

queryAll in interface PrologEngine

Parameters:

goal - prolog term to be query

goals - prolog term array to be query.

Returns:

the list of prolog terms that conform the solution set for the current query.

getProgramMap

public final Map<String,List<PrologClause>> getProgramMap()

Description copied from interface: PrologEngine

Make and return a copy of the clause map present in the current engine. The map key is a functor/arity string and the value is a prolog clause family list.

Specified by:

getProgramMap in interface PrologEngine

Returns:

a clause map present in the current engine.

getProgramClauses

public final Set<PrologClause> getProgramClauses()

Description copied from interface: PrologEngine

Make and return a copy of the clause set present in the current engine.

Specified by:

getProgramClauses in interface PrologEngine

Returns:

a clause set present in the current engine.

isProgramEmpty

public final boolean isProgramEmpty()

Description copied from interface: PrologEngine

Check if the program in main memory is empty returning true if the clause number in the program is 0 and false in otherwise. If wrapped engine not support a dedicated method PrologEngine.isProgramEmpty() will be defined like PrologEngine#getProgramSize()==0;.

Specified by:

isProgramEmpty in interface PrologEngine

Returns:

true if the clause number in the program is 0 and false in otherwise.

currentPredicates

public final Set<PrologIndicator> currentPredicates()

Description copied from interface: PrologEngine

Predicate set defined in the wrapped prolog engine. The predicate set will be constituted by the supported built-ins predicate in the wrapped prolog engine and user defined predicates present in the prolog program/database. More formally current predicate set is defined by the union between user defined predicates and prolog engine built-ins.

 Set<PrologIndicator> cp = new HashSet<PrologIndicator>();
 cp.addAll(getPredicates());
 cp.addAll(getBuiltIns());
 

Specified by:

currentPredicates in interface PrologEngine

Returns:

Defined Predicate Set.

newQueryBuilder

public final io.github.prolobjectlink.prolog.DefaultQueryBuilder newQueryBuilder()

Description copied from interface: PrologEngine

Create a new query builder instance to build prolog goal programmatically.

Specified by:

newQueryBuilder in interface PrologEngine

Returns:

a new query builder instance

newClauseBuilder

public final io.github.prolobjectlink.prolog.DefaultClauseBuilder newClauseBuilder()

Description copied from interface: PrologEngine

Create a new clause builder instance to build prolog clauses programmatically.

Specified by:

newClauseBuilder in interface PrologEngine

Returns:

a new clause builder instance

runOnOSX

public final boolean runOnOSX()

Description copied from interface: PrologEngine

Check if the host operating system name refer to OsX.

Specified by:

runOnOSX in interface PrologEngine

Returns:

true if the host operating system name refer to OsX and false otherwise.

runOnWindows

public final boolean runOnWindows()

Description copied from interface: PrologEngine

Check if the host operating system name refer to Windows OS.

Specified by:

runOnWindows in interface PrologEngine

Returns:

true if the host operating system name refer to Windows OS and false otherwise.

runOnLinux

public final boolean runOnLinux()

Description copied from interface: PrologEngine

Check if the host operating system name refer to Linux OS.

Specified by:

runOnLinux in interface PrologEngine

Returns:

true if the host operating system name refer to Linux OS and false otherwise.

getOSName

public final String getOSName()

Description copied from interface: PrologEngine

Return the host operating system name. Is a shortcut to System.getProperty("os.name");.

Specified by:

getOSName in interface PrologEngine

Returns:

the host operating system name.

getOSVersion

public final String getOSVersion()

Description copied from interface: PrologEngine

Return the host operating system version. Is a shortcut to System.getProperty("os.version");.

Specified by:

getOSVersion in interface PrologEngine

Returns:

the host operating system version.

getOSArch

public final String getOSArch()

Description copied from interface: PrologEngine

Return the host operating system architecture. Is a shortcut to System.getProperty("os.arch");.

Specified by:

getOSArch in interface PrologEngine

Returns:

the host operating system architecture.

getLogger

public final PrologLogger getLogger()

Description copied from interface: PrologEngine

Get the prolog system logger instance to report any errors or exceptions

Specified by:

getLogger in interface PrologEngine

Returns:

prolog system logger instance

toTerm

protected final <K extends PrologTerm> K toTerm(Object o,
                                                Class<K> from)

toTermMapArray

protected final <K extends PrologTerm,V> Map<String,PrologTerm>[] toTermMapArray(Map<String,V>[] map,
                                                                                 Class<K> from)

fromTerm

protected final <K> K fromTerm(PrologTerm term,
                               Class<K> to)

fromTerm

protected final <K> K fromTerm(PrologTerm head,
                               PrologTerm[] body,
                               Class<K> to)

removeQuoted

protected final String removeQuoted(String functor)

toString

public final String toString()

Overrides:

toString in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(Object object)

Overrides:

equals in class Object