package com.bigdata.rdf.sparql.ast;
import java.util.Map;
import com.bigdata.bop.BOp;
import com.bigdata.bop.IValueExpression;
import com.bigdata.rdf.internal.IV;
/**
* AST node for value expressions.
*
* @author <a href="mailto:thompsonbry@users.sourceforge.net">Bryan Thompson</a>
* @version $Id$
*/
public abstract class ValueExpressionNode extends ASTBase implements
IValueExpressionNode {
/**
*
*/
private static final long serialVersionUID = 1L;
interface Annotations extends ASTBase.Annotations {
/**
* The {@link IValueExpression}.
*
* Note: This is really an instance of cached data. If the argument
* corresponding the the {@link IValueExpressionNode} is updated, this
* annotation must be re-computed.
*/
String VALUE_EXPR = "valueExpr";
}
/**
* @deprecated This was just for compatibility with SOp2ASTUtility. It is
* only used by the test suite now. It should be removed now
* that we are done with the SPARQL to AST direct translation.
*/
@Deprecated
public ValueExpressionNode(final IValueExpression<? extends IV> ve) {
super(BOp.NOARGS, null/* anns */);
setProperty(Annotations.VALUE_EXPR, ve);
}
/**
* Constructor required for {@link com.bigdata.bop.BOpUtility#deepCopy(FilterNode)}.
*/
public ValueExpressionNode(final ValueExpressionNode op) {
super(op);
}
/**
* Required shallow copy constructor.
*/
public ValueExpressionNode(final BOp[] args, final Map<String, Object> anns) {
super(args, anns);
}
/**
* Return <code>true</code> iff this is a {@link ConstantNode}.
*/
public final boolean isConstant() {
return this instanceof ConstantNode;
}
/**
* Return <code>true</code> iff this is a {@link VarNode}.
*/
public final boolean isVariable() {
return this instanceof VarNode;
}
/**
* Return <code>true</code> iff this is a {@link FunctionNode}.
*/
public final boolean isFunction() {
return this instanceof FunctionNode;
}
final public IValueExpression<? extends IV> getRequiredValueExpression() {
final IValueExpression<? extends IV> valueExpr = getValueExpression();
if (valueExpr == null)
throw new IllegalStateException("ValueExpression not set: " + this);
return valueExpr;
}
@SuppressWarnings({ "rawtypes", "unchecked" })
public IValueExpression<? extends IV> getValueExpression() {
return (IValueExpression) getProperty(Annotations.VALUE_EXPR);
}
/**
* Called by AST2BOpUtility to populate the value expression nodes
* with value expressions.
*/
@SuppressWarnings({ "rawtypes" })
public void setValueExpression(final IValueExpression<? extends IV> ve) {
setProperty(Annotations.VALUE_EXPR, ve);
}
public void invalidate() {
setProperty(Annotations.VALUE_EXPR, null);
}
public String toShortString() {
// return super.toString();
return getClass().getSimpleName() + "(" + getValueExpression() + ")";
}
}