Application: gvSIG desktop » Library: org.gvsig.tools

/**

 * gvSIG. Desktop Geographic Information System.

 *

 * Copyright (C) 2007-2013 gvSIG Association.

 *

 * This program is free software; you can redistribute it and/or

 * modify it under the terms of the GNU General Public License

 * as published by the Free Software Foundation; either version 2

 * of the License, or (at your option) any later version.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,

 * MA  02110-1301, USA.

 *

 * For any additional information, do not hesitate to contact us

 * at info AT gvsig.com, or visit our website www.gvsig.com.

 */

/* gvSIG. Geographic Information System of the Valencian Government

*

* Copyright (C) 2007-2008 Infrastructures and Transports Department

* of the Valencian Government (CIT)

*

* This program is free software; you can redistribute it and/or

* modify it under the terms of the GNU General Public License

* as published by the Free Software Foundation; either version 2

* of the License, or (at your option) any later version.

*

* This program is distributed in the hope that it will be useful,

* but WITHOUT ANY WARRANTY; without even the implied warranty of

* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

* GNU General Public License for more details.

*

* You should have received a copy of the GNU General Public License

* along with this program; if not, write to the Free Software

* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,

* MA  02110-1301, USA.

*

*/

/*

* AUTHORS (In addition to CIT):

* 2009 IVER T.I   {{Task}}

*/

package org.gvsig.tools.persistence.impl;

import java.util.ArrayList;

import java.util.Iterator;

import java.util.LinkedHashMap;

import java.util.List;

import java.util.Map;

import java.util.Map.Entry;

import org.gvsig.tools.persistence.PersistenceFactory;

import org.gvsig.tools.persistence.PersistenceManager;

import org.gvsig.tools.persistence.PersistentState;

import org.gvsig.tools.persistence.exception.PersistenceClassNotRegistered;

import org.gvsig.tools.persistence.exception.PersistenceException;

import org.gvsig.tools.persistence.exception.PersistenceRuntimeException;

import org.gvsig.tools.persistence.exception.PersistenceValidateExceptions;

import org.gvsig.tools.persistence.impl.exception.ObjectNotFoundException;

import org.gvsig.tools.persistence.impl.exception.PersistenceIDNotLoadedException;

import org.gvsig.tools.persistence.spi.PersistentContextServices;

import org.gvsig.tools.persistence.spi.PersistentIdentifier;

import org.gvsig.tools.persistence.spi.PersistentStateServices;

public class DefaultPersistentContext implements PersistentContextServices {

        private static int IdentifiersCounter = 1; 

        private Map idToReference;

        private Map objToReference;

        private PersistentIdentifier rootId;

        private PersistenceManager manager;

        private boolean collectErrors;

        private PersistenceException errors;

        private boolean validated;

        public DefaultPersistentContext(PersistenceManager manager) {

                this.manager = manager;

                this.collectErrors = false;

                this.errors = null;

                this.validated = false;

                // Use LinkedHashMap for predictable order when save to a file

                this.idToReference = new LinkedHashMap(); 

                this.objToReference = new LinkedHashMap();

        }

        private class DefaultPersistentIdentifier implements PersistentIdentifier, Comparable {

                private String value;

                DefaultPersistentIdentifier(String value) {

                        this.value = value;

                }

//                String getValue() {

//                        return value;

//                }

                public boolean equals(Object obj) {

                        if (!(obj instanceof DefaultPersistentIdentifier)) {

                                return false;

                        }

                        return value == ((DefaultPersistentIdentifier) obj).value;

                }

                public boolean hasValue(Object value) {

                        return this.value.equals(value);

                }

                public int hashCode() {

                        return value.hashCode();

                }

                public String toString() {

                        return value;

                }

                public int compareTo(Object obj) {

                        if (!(obj instanceof DefaultPersistentIdentifier)) {

                                return -1;

                        }

                        return value.compareTo( ((DefaultPersistentIdentifier) obj).value) ;

                }

        }

        private class ContextValue implements ObjectReference, Comparable {

                private Object obj;

                private PersistentState state;

                private PersistentIdentifier id;

                ContextValue(PersistentIdentifier id, PersistentState state) {

                        this.id = id;

                        this.state = state;

                        this.obj = null;

                }

//                public void update() throws PersistenceException {

//                        if( this.obj == null ) {

//                                updateObjectInReference(this);

//                        }

//                }

                public boolean hasObject() {

                        return this.obj != null;

                }

//                public boolean hasState() {

//                        return this.state != null;

//                }

                public Object getObject() {

                        if( this.obj == null ) {

                                try {

                                        updateObjectInReference(this);

                                } catch (PersistenceException e) {

                                        throw new PersistenceRuntimeException(e);

                                }

                        }

                        return this.obj;

                }

                public PersistentState getState() {

                        return this.state;

                }

                public PersistentIdentifier getId() {

                        return this.id;

                }

                protected void update(Object object) {

                        this.obj = object;

                }

                public boolean equals(Object obj) {

                        if (!(obj instanceof ContextValue)) {

                                return false;

                        }

                        return id.equals(((ContextValue) obj).id);

                }

                public int hashCode() {

                        return id.hashCode();

                }

                public String toString() {

                        String idStr = id == null ? "null" : id.toString();

                        return getClass().getName().concat(": id = ").concat(idStr);

                }

                public int compareTo(Object arg0) {

                        if (!(obj instanceof ContextValue)) {

                                return -1;

                        }

                        return ((DefaultPersistentIdentifier)id).compareTo(((ContextValue) obj).id);

                }

        }

        public PersistentIdentifier getNewIdentifier() {

                return new DefaultPersistentIdentifier(String.valueOf( IdentifiersCounter++));

        }

        public PersistentIdentifier getIdentifier(String id) throws PersistenceException {

                Iterator it = this.idToReference.values().iterator();

                while( it.hasNext() ) {

                        ContextValue value = (ContextValue) it.next();

                        if( ((DefaultPersistentIdentifier)(value.getId())).hasValue(id) ) {

                                return value.getId();

                        }

                }

                return new DefaultPersistentIdentifier(id);

        }

        public ObjectReference add(PersistentIdentifier id) throws PersistenceException  {

                this.validated = false;

                ContextValue value = (ContextValue) idToReference.get(id);

                if (value == null ) {

                        value = new ContextValue(id, null);

                        idToReference.put(value.getId(), value);

                }

                return value;

        }

        public ObjectReference add(PersistentState state, Object obj) throws PersistenceException  {

                this.validated = false;

                PersistentIdentifier id = ((PersistentStateServices)state).getId();

                ContextValue value = (ContextValue) idToReference.get(id);

                if (value == null ) {

                        value = new ContextValue( id, state);

                        idToReference.put(value.getId(), value);

                }

                if( value.getState() == null ) {

                        value.state = state;

                }

                if( obj != null ) {

                        value.update(obj);

                        objToReference.put(obj,value);

                }

                return value;

        }

        public ObjectReference get(PersistentState state) throws PersistenceException {

                PersistentIdentifier id = ((PersistentStateServices)state).getId();

                ContextValue ref = (ContextValue) idToReference.get(id);

                if (ref == null ) {

                        ref = new ContextValue(id, state);

                        idToReference.put(id, ref);

                }

                return ref;

        }

        public ObjectReference get(PersistentIdentifier id) {

                ContextValue value = (ContextValue) idToReference.get(id);

                return value;

        }

        public ObjectReference get(Object obj) {

                return (ContextValue) objToReference.get(obj);

        }

        private void updateObjectInReference(ContextValue ref) throws PersistenceException {

                /*

                 * Note: this method is used by the inner class Reference.

                 */

                PersistentStateServices state = (PersistentStateServices) ref.getState();

                PersistenceFactory factory = manager.getFactories().get(state);

                if (factory == null) {

                        /*

                         * This happens if persistence refers to objects

                         * of a missing plugin (example: persistence

                         * has data about oracle connections but we dont have

                         * the oracle plugin in the current execution)

                         */

                    String classname = "";

                    if (state == null) {

                        classname = "[State is null]";

                    } else {

                        classname = state.getTheClassName();

                        if (classname == null) {

                            classname = "[Null]";

                        }

                    }

                        throw new PersistenceClassNotRegistered(classname);

                }

                // This can be done in two step to avoid cyclic references

                state.setFactory(factory);

                ref.update( factory.createFromState(state) );

                factory.loadFromState(state, ref.getObject());

                objToReference.put(ref.getObject(), ref);

        }

        public void update(ObjectReference ref) throws PersistenceException {

                this.validated = false;

                this.updateObjectInReference((ContextValue) ref);

        }

        private void updateAll() throws PersistenceException {

                Iterator it = idToReference.entrySet().iterator();

                while ( it.hasNext() ) {

                        ContextValue ref = (ContextValue) ((Entry) it.next()).getValue();

                        this.update(ref);

                }

        }

        public void clear() {

                this.validated = false;

                Iterator it = idToReference.entrySet().iterator();

                while ( it.hasNext() ) {

                        ContextValue ref = (ContextValue) ((Entry) it.next()).getValue();

                        ref.update(null);

                }

        }

        public Iterator iterator() {

                final class StatesIterator implements Iterator {

                        private Iterator referenceIterator;

                        StatesIterator(Map idToReference) {

                                this.referenceIterator = idToReference.entrySet().iterator();

                        }

//                        StatesIterator(Map idToReference) {

//                                List values = new ArrayList(); 

//                                values.addAll(idToReference.values());

//                                Collections.sort(values);

//                                this.referenceIterator = values.iterator();

//                        }

                        public boolean hasNext() {

                                return referenceIterator.hasNext();

                        }

                        public Object next() {

                                ContextValue ref = (ContextValue) ((Entry) referenceIterator.next()).getValue();

//                                ContextValue ref = (ContextValue) referenceIterator.next();

                                return ref.getState();

                        }

                        public void remove() {

                                throw new UnsupportedOperationException();

                        }

                }

                return new StatesIterator(idToReference);

        }

        public PersistentState getState(Integer id)

                        throws PersistenceException {

                ContextValue ref = (ContextValue) this.get(id);

                if (ref == null) {

                        throw new PersistenceIDNotLoadedException(id);

                }

                return ref.getState();

        }

        public PersistentState getState(Object obj)

                        throws PersistenceException {

                ContextValue ref = (ContextValue) this.get(obj);

                if (ref == null) {

                        return null;

                }

                return ref.getState();

        }

        public Object getObject(Integer id) throws PersistenceException {

                ContextValue ref = (ContextValue) this.get(id);

                if (ref == null) {

                        throw new PersistenceIDNotLoadedException(id);

                }

                return ref.getObject();

        }

        public PersistentIdentifier getId(Object obj) throws PersistenceException {

                ContextValue ref = (ContextValue) this.get(obj);

                if( ref != null ) {

                        return ref.getId();

                }

                this.updateAll();

                ref = (ContextValue) this.get(obj);

                if (ref == null) {

                        throw new ObjectNotFoundException();

                }

                return ref.getId();                

        }

        public void setRootId(PersistentIdentifier id) {

                this.rootId = id;

        }

        public ObjectReference getRoot() throws PersistenceException {

                ObjectReference root = this.get(this.rootId); 

                return  root;

        }

        public void setCollectErrors(boolean collectErrors) {

                this.collectErrors = collectErrors;

        }

        public boolean getCollectErrors() {

                return this.collectErrors;

        }

        public void addError(Throwable cause) {

                if( this.errors == null ) {

                        this.errors = new PersistenceException();

                }

                this.errors.add(cause);

        }

        public PersistenceException getErrors() {

                return this.errors;

        }

        public void validate(int mode) throws PersistenceValidateExceptions {

                if( this.validated ) {

                        return;

                }

                List exceptions = new ArrayList();

                Iterator it = this.iterator();

                while( it.hasNext() ) {

                        PersistentState astate = (PersistentState) it.next();

                        try {

                                this.manager.validate(astate,mode);

                        } catch(Exception e) {

                                exceptions.add(e);

                        }

                }

                this.validated=true;

                if (exceptions.size() > 0) {

                        throw  new PersistenceValidateExceptions(exceptions);

                }                

        }

}