/*
* GeoTools - The Open Source Java GIS Toolkit
* http://geotools.org
*
* (C) 2002-2008, Open Source Geospatial Foundation (OSGeo)
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation;
* version 2.1 of the License.
*
* This library 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
* Lesser General Public License for more details.
*/
package org.geotools.data.postgis.fidmapper;
import java.io.IOException;
import java.sql.Connection;
import java.sql.SQLException;
import java.sql.Statement;
import java.sql.Types;
import org.geotools.data.DataSourceException;
import org.geotools.data.jdbc.datasource.DataSourceFinder;
import org.geotools.data.jdbc.datasource.UnWrapper;
import org.geotools.data.jdbc.fidmapper.AbstractFIDMapper;
import org.geotools.data.jdbc.fidmapper.FIDMapper;
import org.opengis.feature.simple.SimpleFeature;
import org.postgresql.PGStatement;
/**
* Supports the creation of a Feature ID based on the Potgres row OID field.
* <p>
* This is <b>NOT</b> a stable approach for FID (as updates and so on will change the
* OID), but it will be our best guess in the case of read only access where an
* index is not present.
*
* @author wolf
*
* @source $URL$
*/
public class OIDFidMapper extends AbstractFIDMapper {
/** <code>serialVersionUID</code> field */
private static final long serialVersionUID = 3257569520561763632L;
/**
* @see org.geotools.data.jdbc.fidmapper.FIDMapper#initSupportStructures()
*/
public void initSupportStructures() {
// nothing to do, oid are supported in the table or not depending on
// database configuration and table creation commands (not sure)
}
/**
* @see org.geotools.data.jdbc.fidmapper.FIDMapper#getID(java.lang.Object[])
*/
public String getID(Object[] attributes) {
return attributes[0].toString();
}
/**
* Will always return an emtpy array since OIDs are not updatable,
* so we don't try to parse the Feature ID at all.
* Um - this causes failures in SQLEncoder - that may be the place
* to fix it, but I'm putting it in here for now. I believe that
* the oid will not try to get updated since auto increment
* is set to false.
* @see org.geotools.data.jdbc.fidmapper.FIDMapper#getPKAttributes(java.lang.String)
*/
public Object[] getPKAttributes(String FID) throws IOException {
try {
return new Object[] { new Long(Long.parseLong(FID)) };
} catch (NumberFormatException nfe) {
//if we get a really bad featureid we want to return something
//that will not mess up the database and throw an exception,
//we just want to not match against it, so we return -1
return new Object[] { new Integer(-1) };
}
}
/**
* @see org.geotools.data.jdbc.fidmapper.FIDMapper#createID(java.sql.Connection, org.geotools.feature.Feature, Statement)
*/
public String createID(Connection conn, SimpleFeature feature, Statement statement) throws IOException {
try {
if(!(statement instanceof PGStatement)) {
UnWrapper uw = DataSourceFinder.getUnWrapper(statement);
if(uw != null)
statement = uw.unwrap(statement);
}
PGStatement pgStatement = (PGStatement) statement;
return String.valueOf(pgStatement.getLastOID());
} catch (SQLException e) {
throw new DataSourceException("Problems occurred while getting last generate oid from Postgresql statement", e);
} catch (ClassCastException e) {
throw new DataSourceException("Statement is not a PGStatement. OIDFidMapper can be used only with Postgres!", e);
}
}
/**
* @see org.geotools.data.jdbc.fidmapper.FIDMapper#returnFIDColumnsAsAttributes()
*/
public boolean returnFIDColumnsAsAttributes() {
return false;
}
/**
* @see org.geotools.data.jdbc.fidmapper.FIDMapper#getColumnCount()
*/
public int getColumnCount() {
return 1;
}
/**
* @see org.geotools.data.jdbc.fidmapper.FIDMapper#getColumnName(int)
*/
public String getColumnName(int colIndex) {
return "oid";
}
/**
* @see org.geotools.data.jdbc.fidmapper.FIDMapper#getColumnType(int)
*/
public int getColumnType(int colIndex) {
return Types.NUMERIC;
}
/**
* @see org.geotools.data.jdbc.fidmapper.FIDMapper#getColumnSize(int)
*/
public int getColumnSize(int colIndex) {
return 8;
}
/**
* @see org.geotools.data.jdbc.fidmapper.FIDMapper#getColumnDecimalDigits(int)
*/
public int getColumnDecimalDigits(int colIndex) {
return 0;
}
/**
* @see org.geotools.data.jdbc.fidmapper.FIDMapper#isAutoIncrement(int)
*/
public boolean isAutoIncrement(int colIndex) {
return true;
}
/**
* @return {@code true} if fid can be parsed to a long, as OID's are longs
* @see FIDMapper#isValid(String)
*/
public boolean isValid(String fid) {
try{
Long.parseLong(fid, 10);
}catch(NumberFormatException e){
return false;
}
return true;
}
}