/*
* 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;
import java.io.IOException;
import org.opengis.feature.simple.SimpleFeatureType;
/**
* A Default FIDReader. Just auto-increments an index. May be sufficient for
* files, representing rows in a file. For jdbc datasources a
* ResultSetFIDReader should be used.
*
* @author Chris Holmes
* @source $URL$
* @version $Id$
*/
public class DefaultFIDReader implements FIDReader {
protected static final String CLOSE_MESG = "Close has already been called"
+ " on this FIDReader";
private int len;
protected int index = 0;
protected StringBuffer buffer;
public DefaultFIDReader(String typeName) {
buffer = new StringBuffer(typeName);
buffer.append('.');
len = typeName.length() + 1;
}
public DefaultFIDReader(SimpleFeatureType featureType) {
this(featureType.getTypeName());
}
/**
* Release any resources associated with this reader
*/
public void close() {
index = -1;
}
/**
* Does another set of attributes exist in this reader?
*
* @return <code>true</code> if more attributes exist
*
* @throws IOException If closed
*/
public boolean hasNext() throws IOException {
if (index < 0) {
throw new IOException(CLOSE_MESG);
}
return index < Integer.MAX_VALUE;
}
/**
* Read the attribute at the given index.
*
* @return Attribute at index
*
* @throws IOException If closed
*/
public String next() throws IOException {
if (index < 0) {
throw new IOException(CLOSE_MESG);
}
buffer.setLength(len);
buffer.append(++index);
return buffer.toString();
}
}