// Copyright 2005 The Apache Software Foundation
//
// 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 org.apache.tapestry.form.validator;
import java.util.Collection;
import org.apache.tapestry.IMarkupWriter;
import org.apache.tapestry.IRequestCycle;
import org.apache.tapestry.form.FormComponentContributorContext;
import org.apache.tapestry.form.IFormComponent;
import org.apache.tapestry.form.ValidationMessages;
import org.apache.tapestry.json.JSONObject;
import org.apache.tapestry.multipart.UploadPart;
import org.apache.tapestry.valid.ValidationConstants;
import org.apache.tapestry.valid.ValidationConstraint;
import org.apache.tapestry.valid.ValidationStrings;
import org.apache.tapestry.valid.ValidatorException;
/**
* {@link org.apache.tapestry.form.validator.Validator} that ensures a value was supplied.
*
* @author Howard Lewis Ship
* @since 4.0
*/
public class Required extends BaseValidator
{
public Required()
{
}
public Required(String initializer)
{
super(initializer);
}
public boolean getAcceptsNull()
{
return true;
}
public void validate(IFormComponent field, ValidationMessages messages, Object object)
throws ValidatorException
{
if ((object == null)
|| (String.class.isInstance(object) && (((String) object).length() == 0))
|| (Collection.class.isInstance(object) && ((Collection) object).isEmpty())
|| (UploadPart.class.isInstance(object) && ((UploadPart) object).getSize() < 1))
{
String message = buildMessage(messages, field);
throw new ValidatorException(message, ValidationConstraint.REQUIRED);
}
}
private String buildMessage(ValidationMessages messages, IFormComponent field)
{
return messages.formatValidationMessage(
getMessage(),
ValidationStrings.REQUIRED_FIELD,
new Object[]
{ field.getDisplayName() });
}
public void renderContribution(IMarkupWriter writer, IRequestCycle cycle,
FormComponentContributorContext context, IFormComponent field)
{
context.registerForFocus(ValidationConstants.REQUIRED_FIELD);
JSONObject profile = context.getProfile();
accumulateProperty(profile, ValidationConstants.REQUIRED, field.getClientId());
accumulateProfileProperty(field, profile,
ValidationConstants.REQUIRED, buildMessage(context, field));
}
/**
* Returns true, that's what Required means!
*/
public boolean isRequired()
{
return true;
}
}