001    /*
002     * Copyright 2002-2005 the original author or authors.
003     * 
004     * Licensed under the Apache License, Version 2.0 (the "License");
005     * you may not use this file except in compliance with the License.
006     * You may obtain a copy of the License at
007     * 
008     *      http://www.apache.org/licenses/LICENSE-2.0
009     * 
010     * Unless required by applicable law or agreed to in writing, software
011     * distributed under the License is distributed on an "AS IS" BASIS,
012     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013     * See the License for the specific language governing permissions and
014     * limitations under the License.
015     */
016    package org.springframework.binding.validation.support;
017    
018    import java.util.Collections;
019    import java.util.Set;
020    
021    import org.springframework.binding.validation.ValidationResults;
022    import org.springframework.core.style.ToStringCreator;
023    import org.springframework.richclient.core.Severity;
024    
025    /**
026     * An implementation of ValidationResults that contains no results. 
027     * 
028     * @author Oliver Hutchison
029     */
030    public class EmptyValidationResults implements ValidationResults {
031    
032        /**
033         * The singleton instance of this class.
034         */
035        public static final ValidationResults INSTANCE = new EmptyValidationResults();
036    
037        protected EmptyValidationResults() {
038        }
039    
040        /**
041         * Always returns <code>false</code>
042         */
043        public boolean getHasErrors() {
044            return false;
045        }
046    
047        /**
048         * Always returns <code>false</code>
049         */
050        public boolean getHasWarnings() {
051            return false;
052        }
053    
054        /**
055         * Always returns <code>false</code>
056         */
057        public boolean getHasInfo() {
058            return false;
059        }
060    
061        /**
062         * Always returns 0
063         */
064        public int getMessageCount() {
065            return 0;
066        }
067    
068        /**
069         * Always returns 0
070         */
071        public int getMessageCount(Severity severity) {
072            return 0;
073        }
074    
075        /**
076         * Always returns 0
077         */
078        public int getMessageCount(String propertyName) {
079            return 0;
080        }
081    
082        /**
083         * Always returns an empty list.
084         */
085        public Set getMessages() {
086            return Collections.EMPTY_SET;
087        }
088    
089        /**
090         * Always returns an empty list.
091         */
092        public Set getMessages(Severity severity) {
093            return Collections.EMPTY_SET;
094        }
095    
096        /**
097         * Always returns an empty list.
098         */
099        public Set getMessages(String propertyName) {
100            return Collections.EMPTY_SET;
101        }
102        
103        public String toString() {
104            return new ToStringCreator(this).toString();
105        }
106    }