| /* |
| * 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 org.apache.openjpa.kernel.exps; |
| |
| import org.apache.openjpa.kernel.Filters; |
| import org.apache.openjpa.kernel.StoreContext; |
| |
| /** |
| * An in-memory representation of a simple case expression |
| * |
| * @author Catalina Wei |
| */ |
| public class SimpleCase extends Val { |
| |
| private static final long serialVersionUID = 1L; |
| private final Val _caseOperand; |
| private final Exp[] _exp; |
| private final Val _val; |
| |
| SimpleCase(Val caseOperand, Exp[] exp, Val val) { |
| _caseOperand = caseOperand; |
| _exp = exp; |
| _val = val; |
| } |
| |
| @Override |
| protected Object eval(Object candidate, Object orig, StoreContext ctx, |
| Object[] params) { |
| Object o1 = _caseOperand.eval(candidate, orig, ctx, params); |
| for (Exp exp : _exp) { |
| Object o2 = ((WhenScalar) exp).getVal1(). |
| eval(candidate, orig, ctx, params); |
| if (o1 != null && o2 != null) { |
| Class c = Filters.promote(o1.getClass(), o2.getClass()); |
| o1 = Filters.convert(o1, c); |
| o2 = Filters.convert(o2, c); |
| } |
| if (compare(o1, o2)) |
| return ((WhenScalar) exp).getVal2(). |
| eval(candidate, orig, ctx, params); |
| else |
| continue; |
| } |
| return _val.eval(candidate, orig, ctx, params); |
| } |
| |
| protected Object eval(Object candidate,StoreContext ctx, |
| Object[] params) { |
| Object o1 = _caseOperand.eval(candidate, null, ctx, params); |
| for (Exp exp : _exp) { |
| Object o2 = ((WhenScalar) exp).getVal1(). |
| eval(candidate, null, ctx, params); |
| if (o1 != null && o2 != null) { |
| Class c = Filters.promote(o1.getClass(), o2.getClass()); |
| o1 = Filters.convert(o1, c); |
| o2 = Filters.convert(o2, c); |
| } |
| if (compare(o1, o2)) |
| return ((WhenScalar) exp).getVal2(). |
| eval(candidate, null, ctx, params); |
| else |
| continue; |
| } |
| return _val.eval(candidate, null, ctx, params); |
| } |
| |
| /** |
| * Compare the two values. |
| */ |
| protected boolean compare(Object o1, Object o2) { |
| return (o1 == null && o2 == null) |
| || (o1 != null && o1.equals(o2)); |
| } |
| |
| @Override |
| public Class getType() { |
| Class c1 = _val.getType(); |
| for (Exp exp : _exp) { |
| Class c2 = ((WhenScalar) exp).getVal1().getType(); |
| c1 = Filters.promote(c1, c2); |
| } |
| return c1; |
| } |
| |
| @Override |
| public void setImplicitType(Class type) { |
| } |
| |
| @Override |
| public void acceptVisit(ExpressionVisitor visitor) { |
| visitor.enter(this); |
| _caseOperand.acceptVisit(visitor); |
| for (Exp exp : _exp) { |
| exp.acceptVisit(visitor); |
| } |
| _val.acceptVisit(visitor); |
| visitor.exit(this); |
| } |
| } |