/*
* Copyright 2015, The Querydsl Team (http://www.querydsl.com/team)
*
* Licensed 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.querydsl.core.types;
import java.util.List;
import java.util.Map;
import com.querydsl.core.JoinExpression;
import com.querydsl.core.QueryMetadata;
/**
* Copies {@code ParameterExpression} bindings from subexpressions to {@link QueryMetadata} in the context
*
* @author tiwe
*
*/
public final class ParamsVisitor implements Visitor<Void, QueryMetadata> {
public static final ParamsVisitor DEFAULT = new ParamsVisitor();
private ParamsVisitor() { }
@Override
public Void visit(Constant<?> expr, QueryMetadata context) {
return null;
}
@Override
public Void visit(FactoryExpression<?> expr, QueryMetadata context) {
visit(expr.getArgs(), context);
return null;
}
@Override
public Void visit(Operation<?> expr, QueryMetadata context) {
visit(expr.getArgs(), context);
return null;
}
@Override
public Void visit(ParamExpression<?> expr, QueryMetadata context) {
return null;
}
@Override
public Void visit(Path<?> expr, QueryMetadata context) {
return null;
}
@Override
public Void visit(SubQueryExpression<?> expr, QueryMetadata context) {
QueryMetadata md = expr.getMetadata();
for (Map.Entry<ParamExpression<?>, Object> entry : md.getParams().entrySet()) {
context.setParam((ParamExpression) entry.getKey(), entry.getValue());
}
visit(md.getGroupBy(), context);
visit(md.getHaving(), context);
for (JoinExpression join : md.getJoins()) {
visit(join.getTarget(), context);
visit(join.getCondition(), context);
}
visit(md.getProjection(), context);
visit(md.getWhere(), context);
return null;
}
@Override
public Void visit(TemplateExpression<?> expr, QueryMetadata context) {
for (Object arg : expr.getArgs()) {
if (arg instanceof Expression<?>) {
((Expression<?>) arg).accept(this, context);
}
}
return null;
}
private void visit(Expression<?> expr, QueryMetadata context) {
if (expr != null) {
expr.accept(this, context);
}
}
private void visit(List<Expression<?>> exprs, QueryMetadata context) {
for (Expression<?> arg : exprs) {
arg.accept(this, context);
}
}
}