package adql.query;
import java.util.NoSuchElementException;
import adql.query.from.ADQLTable;
/*
* This file is part of ADQLLibrary.
*
* ADQLLibrary 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, either version 3 of the License, or
* (at your option) any later version.
*
* ADQLLibrary 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.
*
* You should have received a copy of the GNU Lesser General Public License
* along with ADQLLibrary. If not, see <http://www.gnu.org/licenses/>.
*
* Copyright 2012-2015 - UDS/Centre de Données astronomiques de Strasbourg (CDS),
* Astronomisches Rechen Institut (ARI)
*/
/**
* In ADQL it corresponds to the '*' and '{tableName}.*' items in the SELECT clause.
* It means: 'select all columns'.
*
* @author Grégory Mantelet (CDS;ARI)
* @version 1.4 (06/2015)
*/
public final class SelectAllColumns extends SelectItem {
/** Query in which all columns of all selected tables are selected. */
private ADQLQuery query = null;
/** The table whose all columns must be selected. */
private ADQLTable adqlTable = null;
/**
* Builds a {@link SelectItem} which selects all columns available in the given ADQL query.
*
* @param query The query whose all available columns must be selected.
*/
public SelectAllColumns(final ADQLQuery query){
super(null, null);
this.query = query;
}
/**
* Builds a {@link SelectItem} which selects all columns available in the given table.
*
* @param table The table whose all available columns must be selected.
*/
public SelectAllColumns(final ADQLTable table){
super(null, null);
adqlTable = table;
}
/**
* Builds a {@link SelectAllColumns} by copying the given one.
*
* @param toCopy The {@link SelectAllColumns} to copy.
* @throws Exception If there is an error during the copy.
*/
public SelectAllColumns(SelectAllColumns toCopy) throws Exception{
super(toCopy);
}
/**
* Gets the query whose all available columns must be selected.
*
* @return The ADQL query whose all available columns must be selected,
* or <i>null</i> if the selection does not concern an {@link ADQLQuery} but an {@link ADQLTable}.
*/
public final ADQLQuery getQuery(){
return query;
}
/**
* Sets the query whose all available columns must be selected.
*
* @param query An {@link ADQLQuery} (MUST NOT BE NULL).
*/
public final void setQuery(final ADQLQuery query){
if (query != null){
this.query = query;
adqlTable = null;
setPosition(null);
}
}
/**
* Gets the table whose all columns must be selected.
*
* @return The ADQL table whose all columns must be selected,
* or <i>null</i> if the selection does not concern an {@link ADQLTable} but an {@link ADQLQuery}.
*/
public final ADQLTable getAdqlTable(){
return adqlTable;
}
/**
* Sets the table whose all columns must be selected.
*
* @param table An {@link ADQLTable} (MUST NOT BE NULL).
*/
public final void setAdqlTable(final ADQLTable table){
if (table != null){
adqlTable = table;
query = null;
setPosition(null);
}
}
@Override
public final ADQLObject getCopy() throws Exception{
return new SelectAllColumns(this);
}
@Override
public final String getName(){
return "*";
}
@Override
public final ADQLIterator adqlIterator(){
return new ADQLIterator(){
private boolean tableGot = (adqlTable == null);
@Override
public ADQLObject next() throws NoSuchElementException{
if (tableGot)
throw new NoSuchElementException();
tableGot = true;
return adqlTable;
}
@Override
public boolean hasNext(){
return !tableGot;
}
@Override
public void replace(ADQLObject replacer) throws UnsupportedOperationException, IllegalStateException{
if (replacer == null)
remove();
else if (!tableGot)
throw new IllegalStateException("replace(ADQLObject) impossible: next() has not yet been called !");
else if (!(replacer instanceof ADQLTable))
throw new IllegalStateException("Impossible to replace an ADQLTable by a " + replacer.getClass().getName() + " !");
else{
adqlTable = (ADQLTable)replacer;
setPosition(null);
}
}
@Override
public void remove(){
if (!tableGot)
throw new IllegalStateException("remove() impossible: next() has not yet been called !");
else
throw new UnsupportedOperationException("Impossible to remove the only operand (" + adqlTable.toADQL() + ") from a SelectItem (" + toADQL() + ") !");
}
};
}
@Override
public final String toADQL(){
if (adqlTable != null){
if (adqlTable.hasAlias())
return (adqlTable.isCaseSensitive(IdentifierField.ALIAS) ? ("\"" + adqlTable.getAlias() + "\"") : adqlTable.getAlias()) + ".*";
else
return adqlTable.getFullTableName() + ".*";
}else
return "*";
}
}