/* Copyright 2013 The jeo project. All rights reserved. * * 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 io.jeo.filter; import java.util.Objects; /** * Implementation of IS NULL and IS NOT NULL. * * @author Ian Schneider <ischneider@boundlessgeo.com> */ public class Null<T> extends Filter<T> { final boolean not; final Property prop; public Null(Property prop, boolean not) { Objects.requireNonNull(prop, "property must not be null"); this.prop = prop; this.not = not; } public Null(String prop, boolean not) { this(new Property(prop), not); } public Property property() { return prop; } public boolean negated() { return not; } @Override public boolean test(Object obj) { return prop.has(obj) && (not != (prop.evaluate(obj) == null)); } @Override public <R> R accept(FilterVisitor<R> v, Object obj) { return v.visit(this, obj); } @Override public int hashCode() { int hash = 5; hash = 37 * hash + (this.not ? 1 : 0); hash = 37 * hash + (this.prop != null ? this.prop.hashCode() : 0); return hash; } @Override public boolean equals(Object obj) { if (obj == null) { return false; } if (getClass() != obj.getClass()) { return false; } final Null other = (Null) obj; if (this.not != other.not) { return false; } if (this.prop != other.prop && (this.prop == null || !this.prop.equals(other.prop))) { return false; } return true; } @Override public String toString() { return prop + " IS" + (not ? " NOT" : "") + " NULL"; } }