001package gwt.material.design.client.base.validator;
002
003/*
004 * #%L
005 * GwtBootstrap3
006 * %%
007 * Copyright (C) 2015 GwtBootstrap3
008 * %%
009 * Licensed under the Apache License, Version 2.0 (the "License");
010 * you may not use this file except in compliance with the License.
011 * You may obtain a copy of the License at
012 * 
013 *      http://www.apache.org/licenses/LICENSE-2.0
014 * 
015 * Unless required by applicable law or agreed to in writing, software
016 * distributed under the License is distributed on an "AS IS" BASIS,
017 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
018 * See the License for the specific language governing permissions and
019 * limitations under the License.
020 * #L%
021 */
022
023import com.google.gwt.text.shared.Parser;
024
025import java.text.ParseException;
026
027/**
028 * Parses boolean values from a {@link CharSequence}.
029 * 
030 * @author Steven Jardine
031 */
032public class BooleanParser implements Parser<Boolean> {
033
034    private static BooleanParser instance;
035
036    /**
037     * @return the instance of the {@link BooleanParser}.
038     */
039    public static Parser<Boolean> instance() {
040        if (instance == null) {
041            instance = new BooleanParser();
042        }
043        return instance;
044    }
045
046    /**
047     * Constructor.
048     */
049    protected BooleanParser() {
050        super();
051    }
052
053    @Override
054    public Boolean parse(final CharSequence text) throws ParseException {
055        if (text != null) {
056            String value = text.toString();
057            if (value.equalsIgnoreCase("true") || value.equalsIgnoreCase("Yes")) {
058                return true;
059            }
060            try {
061                Integer i = Integer.valueOf(value);
062                return i != 0;
063            } catch (Exception e) {}
064        }
065        return false;
066    }
067}