    001// Licensed under the Apache License, Version 2.0 (the "License");
    002// you may not use this file except in compliance with the License.
    003// You may obtain a copy of the License at
    004//
    005//     http://www.apache.org/licenses/LICENSE-2.0
    006//
    007// Unless required by applicable law or agreed to in writing, software
    008// distributed under the License is distributed on an "AS IS" BASIS,
    009// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    010// See the License for the specific language governing permissions and
    011// limitations under the License.
    012
    013package org.apache.tapestry5.internal.services;
    014
    015import org.apache.tapestry5.ValueEncoder;
    016import org.apache.tapestry5.commons.services.TypeCoercer;
    017import org.apache.tapestry5.ioc.internal.util.InternalUtils;
    018import org.apache.tapestry5.services.ValueEncoderFactory;
    019
    020/**
    021 * Provides {@link org.apache.tapestry5.ValueEncoder} instances that are backed by the {@link
    022 * org.apache.tapestry5.commons.services.TypeCoercer} service.
    023 */
    024public class TypeCoercedValueEncoderFactory implements ValueEncoderFactory<Object>
    025{
    026    private final TypeCoercer typeCoercer;
    027
    028    public TypeCoercedValueEncoderFactory(TypeCoercer typeCoercer)
    029    {
    030        this.typeCoercer = typeCoercer;
    031    }
    032
    033    public ValueEncoder<Object> create(final Class<Object> type)
    034    {
    035        final boolean blankToNull =
    036                Boolean.class.isAssignableFrom(type) ||
    037                Number.class.isAssignableFrom(type);
    038
    039        return new ValueEncoder<Object>()
    040        {
    041            public String toClient(Object value)
    042            {
    043                return typeCoercer.coerce(value, String.class);
    044            }
    045
    046            public Object toValue(String clientValue)
    047            {
    048                if (blankToNull && InternalUtils.isBlank(clientValue)) {
    049                    return null;
    050                }
    051
    052                return typeCoercer.coerce(clientValue, type);
    053            }
    054        };
    055    }
    056}