/*
* $Id: JGraphSQLBackend.java,v 1.1.1.1 2005/08/06 05:26:45 gaudenz Exp $
*
* Copyright (c) 2001-2005, Gaudenz Alder
*
* See LICENSE file in distribution for licensing details of this source file
*/
package com.jgraph.example.adapter;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Hashtable;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import org.jgraph.graph.DefaultGraphCell;
import org.jgraph.graph.DefaultGraphModel;
import org.jgraph.graph.GraphConstants;
/**
* Maps changes to the graph model to a custom backend, eg. an SQL database.
* (This should use prepared statements.)
*/
public class JGraphSQLBackend implements JGraphAdapterBackend {
protected static final String NO_ID = "0";
protected int lastId = 0;
protected boolean trxInProgress = false;
protected Object vertexPrototype, edgePrototype;
protected Connection conn;
public JGraphSQLBackend(Connection conn, Object vertexPrototype,
Object edgePrototype) throws ClassNotFoundException, SQLException {
this.conn = conn;
this.vertexPrototype = vertexPrototype;
this.edgePrototype = edgePrototype;
try {
update("SET AUTOCOMMIT FALSE");
update("CREATE TABLE entity ( id INTEGER, parent_id INTEGER)");
update("CREATE TABLE relation ( entity_id INTEGER, source_id INTEGER, target_id INTEGER)");
update("CREATE TABLE property ( entity_id INTEGER, key VARCHAR(256), value VARCHAR(256))");
update("CREATE INDEX prp_entity_idx ON property (entity_id)");
update("CREATE INDEX rel_entity_idx ON relation (entity_id)");
update("CREATE INDEX rel_source_idx ON relation (source_id)");
update("CREATE INDEX rel_target_idx ON relation (target_id)");
// Triggers to update the model if the db changes...
// update("CREATE TRIGGER test_trigger AFTER UPDATE ON property CALL
// org.jgraph.studio.business.JGraphStudioSQLBackend.TestTrigger");
update("COMMIT");
} catch (SQLException ex2) {
// this will have no effect on the db
}
}
/*
* (non-Javadoc)
*
* @see org.jgraph.editor.business.JGraphBusinessBackend#valueForCellChanged(org.jgraph.editor.business.JGraphBusinessModel,
* java.lang.Object, java.lang.Object)
*/
public void commit() throws Exception {
if (trxInProgress) {
update("COMMIT");
trxInProgress = false;
}
}
/*
* (non-Javadoc)
*
* @see org.jgraph.editor.business.JGraphBusinessBackend#valueForCellChanged(org.jgraph.editor.business.JGraphBusinessModel,
* java.lang.Object, java.lang.Object)
*/
public void rollback() throws Exception {
if (trxInProgress) {
update("ROLLBACK");
trxInProgress = false;
}
}
/*
* (non-Javadoc)
*
* @see org.jgraph.editor.business.JGraphBusinessBackend#vertexAdded(org.jgraph.editor.business.JGraphBusinessModel,
* java.lang.Object)
*/
public void vertexAdded(JGraphAdapterModel sender, Object vertex,
boolean validate) throws Exception {
if (!validate)
objectAdded(sender.getValue(vertex));
}
/*
* (non-Javadoc)
*
* @see org.jgraph.editor.business.JGraphBusinessBackend#valueForCellChanged(org.jgraph.editor.business.JGraphBusinessModel,
* java.lang.Object, java.lang.Object)
*/
public void edgeAdded(JGraphAdapterModel sender, Object object,
Object source, Object target, boolean validate) throws Exception {
if (!validate) {
Object id = objectAdded(sender.getValue(object));
if (id != null)
update("INSERT INTO relation(entity_id, source_id, target_id) VALUES ("
+ id + ", 0, 0)");
}
}
/*
* (non-Javadoc)
*
* @see org.jgraph.editor.business.JGraphBusinessBackend#valueForCellChanged(org.jgraph.editor.business.JGraphBusinessModel,
* java.lang.Object, java.lang.Object)
*/
protected Object objectAdded(Object object) throws SQLException {
if (object instanceof JGraphSQLEntity) {
JGraphSQLEntity entity = (JGraphSQLEntity) object;
if (entity.getID() == null) {
entity.setID(getNextEntityId());
update("INSERT INTO entity(id) VALUES (" + entity.getID() + ")");
Iterator it = entity.getProperties().entrySet().iterator();
while (it.hasNext()) {
Map.Entry entry = (Map.Entry) it.next();
update("INSERT INTO property(entity_id, key, value) VALUES ("
+ entity.getID()
+ ", '"
+ entry.getKey()
+ "', '"
+ entry.getValue() + "')");
}
}
return entity.getID();
}
return null;
}
/*
* (non-Javadoc)
*
* @see org.jgraph.editor.business.JGraphBusinessBackend#valueForCellChanged(org.jgraph.editor.business.JGraphBusinessModel,
* java.lang.Object, java.lang.Object)
*/
public void cellRemoved(JGraphAdapterModel sender, Object cell,
boolean validate) throws Exception {
Object userObj = sender.getValue(cell);
if (!validate && userObj instanceof JGraphSQLEntity) {
JGraphSQLEntity entity = (JGraphSQLEntity) userObj;
Object entityId = entity.getID();
update("DELETE FROM entity WHERE id = " + entityId);
update("DELETE FROM relation WHERE entity_id = " + entityId);
update("DELETE FROM property WHERE entity_id = " + entityId);
update("UPDATE entity SET parent_id = " + NO_ID
+ " WHERE parent_id = " + entityId);
entity.setID(null);
}
}
public void parentChanged(JGraphAdapterModel sender, Object child,
Object parent, boolean validate) throws Exception {
Object childObj = sender.getValue(child);
Object parentObj = sender.getValue(parent);
if (!validate && childObj instanceof JGraphSQLEntity
&& parentObj instanceof JGraphSQLEntity) {
JGraphSQLEntity childEntity = (JGraphSQLEntity) childObj;
JGraphSQLEntity parentEntity = (JGraphSQLEntity) parentObj;
update("UPDATE entity SET parent_id = " + parentEntity.getID()
+ " where id = " + childEntity.getID());
childEntity.setParent(parentEntity);
}
}
/*
* (non-Javadoc)
*
* @see org.jgraph.editor.business.JGraphBusinessBackend#valueForCellChanged(org.jgraph.editor.business.JGraphBusinessModel,
* java.lang.Object, java.lang.Object)
*/
public void sourceChanged(JGraphAdapterModel sender, Object edge,
Object source, boolean validate) throws Exception {
Object object = sender.getValue(edge);
source = sender.getParentUserObject(source);
if (!validate && object instanceof JGraphSQLRelation) {
JGraphSQLRelation relation = (JGraphSQLRelation) object;
Object id = NO_ID;
if (source instanceof JGraphSQLEntity) {
relation.setSource((JGraphSQLEntity) source);
id = relation.getSource().getID();
} else
relation.setSource(null);
update("UPDATE relation SET source_id = " + id
+ " where entity_id = " + relation.getID());
}
}
/*
* (non-Javadoc)
*
* @see org.jgraph.editor.business.JGraphBusinessBackend#valueForCellChanged(org.jgraph.editor.business.JGraphBusinessModel,
* java.lang.Object, java.lang.Object)
*/
public void targetChanged(JGraphAdapterModel sender, Object edge,
Object target, boolean validate) throws Exception {
Object object = sender.getValue(edge);
target = sender.getParentUserObject(target);
if (!validate && object instanceof JGraphSQLRelation) {
JGraphSQLRelation relation = (JGraphSQLRelation) object;
Object id = NO_ID;
if (target instanceof JGraphSQLEntity) {
relation.setTarget((JGraphSQLEntity) target);
id = relation.getTarget().getID();
} else
relation.setTarget(null);
update("UPDATE relation SET target_id = " + id
+ " where entity_id = " + relation.getID());
}
}
/*
* (non-Javadoc)
*
* @see org.jgraph.editor.business.JGraphBusinessBackend#valueForCellChanged(org.jgraph.editor.business.JGraphBusinessModel,
* java.lang.Object, java.lang.Object)
*/
public void attributesChanged(JGraphAdapterModel sender, Object cell,
Map attributes, boolean validate) throws Exception {
if (!validate) {
if (cell instanceof JGraphSQLEntity) {
propertiesChanged(cell, attributes);
} else {
Object value = GraphConstants.getValue(attributes);
if (value != null) {
Map properties = new Hashtable();
properties.put("value", value);
propertiesChanged(sender.getValue(cell),
properties);
}
}
}
}
/*
* (non-Javadoc)
*
* @see org.jgraph.editor.business.JGraphBusinessBackend#valueForCellChanged(org.jgraph.editor.business.JGraphBusinessModel,
* java.lang.Object, java.lang.Object)
*/
public void propertiesChanged(Object object, Map properties)
throws Exception {
if (object instanceof JGraphSQLEntity) {
JGraphSQLEntity entity = (JGraphSQLEntity) object;
Iterator it = properties.entrySet().iterator();
while (it.hasNext()) {
Map.Entry entry = (Map.Entry) it.next();
// TODO: Handle new attributes here?
propertyChanged(entity, entry.getKey(), entry.getValue());
}
}
}
/*
* (non-Javadoc)
*
* @see org.jgraph.editor.business.JGraphBusinessBackend#valueForCellChanged(org.jgraph.editor.business.JGraphBusinessModel,
* java.lang.Object, java.lang.Object)
*/
public void propertyChanged(JGraphSQLEntity entity, Object key, Object value)
throws Exception {
update("UPDATE property SET value = '" + value + "' where key='" + key
+ "' AND entity_id = " + entity.getID());
}
/*
* This method is called from the Studio UI. (non-Javadoc)
*
* @see org.jgraph.editor.business.JGraphBusinessBackend#valueForCellChanged(org.jgraph.editor.business.JGraphBusinessModel,
* java.lang.Object, java.lang.Object)
*/
public void propertyAdded(JGraphSQLEntity entity, Object key, Object value)
throws Exception {
update("INSERT INTO property(entity_id, key, value) VALUES ("
+ entity.getID() + ", '" + key + "', '" + value + "')");
}
/*
* (non-Javadoc)
*
* @see org.jgraph.editor.business.JGraphBusinessBackend#valueForCellChanged(org.jgraph.editor.business.JGraphBusinessModel,
* java.lang.Object, java.lang.Object)
*/
public Collection findVertices(JGraphAdapterModel sender, Object query,
Object parent) throws SQLException {
Object object = sender.getValue(parent);
String parentClause = (object instanceof JGraphSQLEntity) ? " and parent_id = "
+ ((JGraphSQLEntity) object).getID()
: "";
String whereClause = "where "
+ createFilter(query)
+ parentClause
+ " and not exists (select 1 from relation where relation.entity_id = property.entity_id)";
return findCells(sender, whereClause);
}
protected Collection findCells(JGraphAdapterModel context,
String whereClause) throws SQLException {
Collection objs = find(whereClause);
List result = new ArrayList(objs.size());
Iterator it = objs.iterator();
while (it.hasNext()) {
JGraphSQLEntity entity = (JGraphSQLEntity) it.next();
result.add(createCell(context, entity));
}
return result;
}
public Object getParent(Object object) {
if (object instanceof JGraphSQLEntity)
return ((JGraphSQLEntity) object).getParent();
return null;
}
public Object getSource(Object object) {
if (object instanceof JGraphSQLRelation)
return ((JGraphSQLRelation) object).getSource();
return null;
}
public Object getTarget(Object object) {
if (object instanceof JGraphSQLRelation)
return ((JGraphSQLRelation) object).getTarget();
return null;
}
// All relations with cells (parent, source, target) must be
// set when inserting the cells. the backend only sets the relations
// on the business-object level.
public Object createCell(JGraphAdapterModel context, JGraphSQLEntity entity)
throws SQLException {
Object prototype = (entity instanceof JGraphSQLRelation) ? edgePrototype
: vertexPrototype;
// TODO: Do not create if mapped?
Object vertex = DefaultGraphModel.cloneCell(context, prototype);
if (vertex instanceof DefaultGraphCell) {
DefaultGraphCell cell = (DefaultGraphCell) vertex;
cell.setUserObject(entity);
}
return vertex;
}
/*
* (non-Javadoc)
*
* @see org.jgraph.editor.business.JGraphBusinessBackend#valueForCellChanged(org.jgraph.editor.business.JGraphBusinessModel,
* java.lang.Object, java.lang.Object)
*/
public Collection findEdges(JGraphAdapterModel sender, Object query,
Object parent, Object source, Object target, boolean directed)
throws SQLException {
Object object = sender.getValue(parent);
source = sender.getValue(source);
target = sender.getValue(target);
String parentClause = (object instanceof JGraphSQLEntity) ? " and parent_id = "
+ ((JGraphSQLEntity) object).getID()
: "";
String edgeWhereClause = "1=1 ";
if (source instanceof JGraphSQLEntity) {
JGraphSQLEntity entity = (JGraphSQLEntity) source;
edgeWhereClause += "and source_id = " + entity.getID() + " ";
}
if (target instanceof JGraphSQLEntity) {
JGraphSQLEntity entity = (JGraphSQLEntity) target;
edgeWhereClause += "and target_id = " + entity.getID() + " ";
} else if (!directed && source != null) { // TODO: Shortcut for now...
JGraphSQLEntity entity = (JGraphSQLEntity) source;
edgeWhereClause += "or target_id = " + entity.getID() + " ";
}
String whereClause = "where "
+ createFilter(query)
+ parentClause
+ " and exists (select 1 from relation where relation.entity_id = property.entity_id and ("
+ edgeWhereClause + "))";
return findCells(sender, whereClause);
}
/*
* (non-Javadoc)
*
* @see org.jgraph.editor.business.JGraphBusinessBackend#valueForCellChanged(org.jgraph.editor.business.JGraphBusinessModel,
* java.lang.Object, java.lang.Object)
*/
protected String createFilter(Object query) {
if (query != null && query.toString().length() > 0) {
String[] tokens = query.toString().split(" ");
if (tokens.length > 0) {
String filter = "soundex(value) IN (soundex('" + tokens[0]
+ "')";
for (int i = 1; i < tokens.length; i++)
filter += ", soundex('" + tokens[i] + "')";
return filter + ")";
}
}
return "1=1";
}
/*
* (non-Javadoc)
*
* @see org.jgraph.editor.business.JGraphBusinessBackend#valueForCellChanged(org.jgraph.editor.business.JGraphBusinessModel,
* java.lang.Object, java.lang.Object)
*/
protected Collection find(String whereClause) throws SQLException {
Statement st = (conn != null) ? conn.createStatement() : null;
String sql = "select entity_id, count(entity_id) as ranking from property "
+ whereClause + " group by entity_id order by ranking desc";
println("SQL: " + sql);
ResultSet rs = (st != null) ? st.executeQuery(sql) : null;
List objects = new LinkedList();
while (rs != null && rs.next()) {
Object object = get(rs.getObject(1));
if (object != null)
objects.add(object);
}
if (st != null)
st.close();
return objects;
}
/*
* (non-Javadoc)
*
* @see org.jgraph.editor.business.JGraphBusinessBackend#valueForCellChanged(org.jgraph.editor.business.JGraphBusinessModel,
* java.lang.Object, java.lang.Object)
*/
protected synchronized Object getNextEntityId() {
int id = lastId;
try {
Statement st = (conn != null) ? conn.createStatement() : null;
ResultSet rs = (st != null) ? st
.executeQuery("select max(id) from entity") : null;
if (st != null)
st.close();
if (rs != null && rs.next())
id = rs.getInt(1) + 1;
else
// use local var for ids
lastId++;
} catch (SQLException e) {
// ignore and return lastId
}
return new Integer(id);
}
/*
* (non-Javadoc)
*
* @see org.jgraph.editor.business.JGraphBusinessBackend#valueForCellChanged(org.jgraph.editor.business.JGraphBusinessModel,
* java.lang.Object, java.lang.Object)
*/
public JGraphSQLEntity get(Object id) throws SQLException {
Statement st = (conn != null) ? conn.createStatement() : null;
JGraphSQLEntity entity = null;
ResultSet rs = st
.executeQuery("select id, parent_id from entity where id = "
+ id);
Object entityId = null;
JGraphSQLEntity parent = null;
if (rs.next()) {
entityId = rs.getObject(1);
parent = get(rs.getObject(2));
}
// Assumes that the entity exists
rs = st
.executeQuery("select source_id, target_id from relation where entity_id = "
+ id);
// Fetch the source and target, or create a vertex
if (rs.next()) {
JGraphSQLEntity source = get(rs.getObject(1));
JGraphSQLEntity target = get(rs.getObject(2));
entity = new JGraphSQLRelation(entityId, parent, source, target); // TODO.
// Add
// Parent
} else {
entity = new JGraphSQLEntity(entityId, parent);
}
// Fill-in the properties
rs = st
.executeQuery("select key, value from property where entity_id = "
+ id);
Hashtable properties = new Hashtable();
while (rs.next()) {
String key = rs.getString(1);
String value = rs.getString(2);
if (key != null) {
properties.put(key, value);
}
}
st.close();
entity.setProperties(properties);
return entity;
}
/*
* (non-Javadoc)
*
* @see org.jgraph.editor.business.JGraphBusinessBackend#valueForCellChanged(org.jgraph.editor.business.JGraphBusinessModel,
* java.lang.Object, java.lang.Object)
*/
public synchronized void query(String expression) throws SQLException {
Statement st = (conn != null) ? conn.createStatement() : null;
ResultSet rs = (st != null) ? st.executeQuery(expression) : null;
dump(rs);
st.close();
}
/*
* (non-Javadoc)
*
* @see org.jgraph.editor.business.JGraphBusinessBackend#valueForCellChanged(org.jgraph.editor.business.JGraphBusinessModel,
* java.lang.Object, java.lang.Object)
*/
public void dump(ResultSet rs) throws SQLException {
ResultSetMetaData meta = rs.getMetaData();
int colmax = meta.getColumnCount();
while (rs.next()) {
for (int i = 0; i < colmax; ++i) {
Object o = rs.getObject(i + 1);
if (o != null)
System.out.print(o.toString() + " ");
}
println(" ");
}
}
/*
* (non-Javadoc)
*
* @see org.jgraph.editor.business.JGraphBusinessBackend#valueForCellChanged(org.jgraph.editor.business.JGraphBusinessModel,
* java.lang.Object, java.lang.Object)
*/
public synchronized void update(String expression) throws SQLException {
trxInProgress = true;
Statement st = (conn != null) ? conn.createStatement() : null;
int i = (st != null) ? st.executeUpdate(expression) : 0;
if (i == -1) {
println("db error : " + expression);
} else {
println("SQL: " + expression);
}
if (st != null)
st.close();
}
protected static void println(String msg) {
JGraphAdapterExample.println(msg);
}
}
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