/**
* Copyright (C) 2009-2013 FoundationDB, LLC
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation, either version 3 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 Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package com.foundationdb.ais.model;
import com.foundationdb.ais.model.validation.AISInvariants;
import com.foundationdb.server.collation.AkCollator;
public class IndexColumn implements Visitable
{
// IndexColumn interface
@Override
public String toString()
{
return "IndexColumn(" + column.getName() + ")";
}
public Index getIndex()
{
return index;
}
public Column getColumn()
{
return column;
}
public Integer getPosition()
{
return position;
}
public Integer getIndexedLength()
{
return indexedLength;
}
public Boolean isAscending()
{
return ascending;
}
/** Can this index column be used as part of a <em>covering</em> index? */
public boolean isRecoverable() {
AkCollator collator = column.getCollator();
if (collator == null)
return true;
else
return collator.isRecoverable();
}
// Visitable
/** Visit this instance. */
@Override
public void visit(Visitor visitor) {
visitor.visit(this);
}
public static IndexColumn create(Index index,
Column column,
Integer position,
Boolean ascending,
Integer indexedLength) {
index.checkMutability();
AISInvariants.checkNullField(column, "IndexColumn", "column", "Column");
AISInvariants.checkDuplicateColumnsInIndex(index, column.getColumnar().getName(), column.getName());
IndexColumn indexColumn = new IndexColumn(index, column, position, ascending, indexedLength);
index.addColumn(indexColumn);
return indexColumn;
}
/**
* Create an independent copy of an existing IndexColumn.
* @param index Destination Index.
* @param column Associated Column.
* @param indexColumn IndexColumn to copy.
* @return The new copy of the IndexColumn.
*/
public static IndexColumn create(Index index, Column column, IndexColumn indexColumn, int position) {
return create(index, column, position, indexColumn.ascending, indexColumn.indexedLength);
}
IndexColumn(Index index, Column column, Integer position, Boolean ascending, Integer indexedLength)
{
this.index = index;
this.column = column;
this.position = position;
this.ascending = ascending;
this.indexedLength = indexedLength;
}
// State
private final Index index;
private final Column column;
private final Integer position;
private final Boolean ascending;
private final Integer indexedLength;
}