/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.hp.hpl.jena.query;
import org.apache.jena.atlas.io.IndentedWriter ;
import org.apache.jena.atlas.lib.Lib ;
import org.apache.jena.atlas.logging.Log ;
import com.hp.hpl.jena.graph.Node ;
import com.hp.hpl.jena.sparql.core.Var ;
import com.hp.hpl.jena.sparql.engine.Plan ;
import com.hp.hpl.jena.sparql.expr.E_Function ;
import com.hp.hpl.jena.sparql.expr.Expr ;
import com.hp.hpl.jena.sparql.expr.ExprVar ;
import com.hp.hpl.jena.sparql.serializer.FmtExprSPARQL ;
import com.hp.hpl.jena.sparql.serializer.SerializationContext ;
import com.hp.hpl.jena.sparql.util.ExprUtils ;
import com.hp.hpl.jena.sparql.util.PrintSerializableBase ;
public class SortCondition extends PrintSerializableBase
{
public Expr expression = null ;
public int direction = 0 ;
public SortCondition(Var var, int dir)
{ this(new ExprVar(var),dir) ; }
public SortCondition(Node var, int dir)
{ this(ExprUtils.nodeToExpr(var), dir) ; }
public SortCondition(Expr expr, int dir)
{
expression = expr ;
direction = dir ;
if ( dir != Query.ORDER_ASCENDING && dir != Query.ORDER_DESCENDING && dir != Query.ORDER_DEFAULT )
Log.fatal(this, "Unknown sort direction") ;
}
public void format(FmtExprSPARQL fmt,
IndentedWriter writer)
{
boolean explicitDirection = false ;
// Not always necessary but safe.
// At this point there must be brackets but some forms (e.g. ?x+?y)
// are going to put their own brackets in regardless.
boolean needParens = false ;
if ( direction != Query.ORDER_DEFAULT )
{
// Need parens if the expression isn't going to add them anyway.
if ( expression.isVariable() || expression instanceof E_Function )
// Bracketless by expression formatting
needParens = true ;
}
if ( direction == Query.ORDER_ASCENDING )
{
writer.print("ASC") ;
needParens = true ;
}
if ( direction == Query.ORDER_DESCENDING )
{
writer.print("DESC") ;
needParens = true ;
}
if ( needParens )
writer.print("(") ;
fmt.format(expression) ;
if ( needParens )
writer.print(")") ;
}
/** @return Returns the direction. */
public int getDirection()
{
return direction ;
}
/** @return Returns the expression. */
public Expr getExpression()
{
return expression ;
}
@Override
public int hashCode()
{
int x = this.getDirection() ;
if ( getExpression() != null )
x ^= getExpression().hashCode() ;
return x ;
}
@Override
public boolean equals(Object other)
{
if ( this == other ) return true ;
if ( ! ( other instanceof SortCondition ) )
return false ;
SortCondition sc = (SortCondition)other ;
if ( sc.getDirection() != this.getDirection() )
return false ;
if ( ! Lib.equal(this.getExpression(), sc.getExpression()) )
return false ;
// if ( ! Utils.eq(this.getVariable(), sc.getVariable()) )
// return false ;
return true ;
}
@Override
public void output(IndentedWriter out)
{
out.print(Plan.startMarker) ;
out.print("SortCondition ") ;
FmtExprSPARQL fmt = new FmtExprSPARQL(out, null) ;
format(fmt, out) ;
out.print(Plan.finishMarker) ;
}
@Override
public void output(IndentedWriter out, SerializationContext sCxt)
{
if ( sCxt == null )
sCxt = new SerializationContext() ;
FmtExprSPARQL fmt = new FmtExprSPARQL(out, sCxt) ;
format(fmt, out) ;
}
}