/*
* GeoTools - The Open Source Java GIS Toolkit
* http://geotools.org
*
* (C) 2003-2008, 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.shapefile.indexed;
import java.io.IOException;
import org.geotools.data.FIDReader;
import org.geotools.data.shapefile.ShapefileAttributeReader;
import org.opengis.feature.simple.SimpleFeatureType;
/**
* Reader that returns FeatureIds in a quick fashion.
*
* @author Tommaso Nolli
*
* @source $URL$
*/
public class ShapeFIDReader implements FIDReader {
protected static final String CLOSE_MESG = "Close has already been called"
+ " on this FIDReader";
private boolean opened;
private ShapefileAttributeReader reader;
private int len;
protected StringBuffer buffer;
public ShapeFIDReader(String typeName,
ShapefileAttributeReader reader) {
buffer = new StringBuffer(typeName);
buffer.append('.');
len = typeName.length() + 1;
this.opened = true;
this.reader = reader;
}
public ShapeFIDReader(SimpleFeatureType featureType,
ShapefileAttributeReader reader) {
this(featureType.getTypeName(), reader);
}
/**
* Release any resources associated with this reader
*/
public void close() {
this.opened = false;
}
/**
* This method always returns true, since it is built with a
* <code>ShapefileDataStore.Reader</code> you have to call
* <code>ShapefileDataStore.Reader.hasNext()</code>
*
* @return always return <code>true</code>
*
* @throws IOException
* If closed
*/
public boolean hasNext() throws IOException {
if (!this.opened) {
throw new IOException(CLOSE_MESG);
}
/*
* In DefaultFIDReader this is always called after
* atttributesReader.hasNext so, as we use the same attributeReader,
* we'll return true
*/
return true;
}
/**
* Read the feature id.
*
* @return the Feature Id
*
* @throws IOException
* If closed
*/
public String next() throws IOException {
if (!this.opened) {
throw new IOException(CLOSE_MESG);
}
buffer.delete(len, buffer.length());
buffer.append(reader.getRecordNumber());
return buffer.toString();
}
}