001// Copyright 2004, 2005 The Apache Software Foundation
002//
003// Licensed under the Apache License, Version 2.0 (the "License");
004// you may not use this file except in compliance with the License.
005// You may obtain a copy of the License at
006//
007//     http://www.apache.org/licenses/LICENSE-2.0
008//
009// Unless required by applicable law or agreed to in writing, software
010// distributed under the License is distributed on an "AS IS" BASIS,
011// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
012// See the License for the specific language governing permissions and
013// limitations under the License.
014
015package org.apache.tapestry.form;
016
017import org.apache.hivemind.HiveMind;
018import org.apache.tapestry.IForm;
019import org.apache.tapestry.IMarkupWriter;
020import org.apache.tapestry.IRequestCycle;
021import org.apache.tapestry.multipart.MultipartDecoder;
022import org.apache.tapestry.request.IUploadFile;
023import org.apache.tapestry.valid.ValidatorException;
024
025/**
026 * Form element used to upload files. [ <a
027 * href="../../../../../ComponentReference/Upload.html">Component Reference
028 * </a>]
029 * <p>
030 * As of 4.0, this component can be validated.
031 * 
032 * @author Howard Lewis Ship
033 * @author Paul Ferraro
034 * @since 1.0.8
035 */
036
037public abstract class Upload extends AbstractFormComponent implements ValidatableField
038{
039    public abstract void setFile(IUploadFile file);
040
041    /**
042     * @see org.apache.tapestry.form.AbstractFormComponent#renderFormComponent(org.apache.tapestry.IMarkupWriter,
043     *      org.apache.tapestry.IRequestCycle)
044     */
045    protected void renderFormComponent(IMarkupWriter writer, IRequestCycle cycle)
046    {
047        // Force the form to use the correct encoding type for file uploads.
048        IForm form = getForm();
049        
050        form.setEncodingType("multipart/form-data");
051        
052        renderDelegatePrefix(writer, cycle);
053        
054        writer.beginEmpty("input");
055        writer.attribute("type", "file");
056        writer.attribute("name", getName());
057
058        if (isDisabled())
059        {
060            writer.attribute("disabled", "disabled");
061        }
062        
063        renderIdAttribute(writer, cycle);
064        
065        renderDelegateAttributes(writer, cycle);
066        
067        getValidatableFieldSupport().renderContributions(this, writer, cycle);
068        
069        renderInformalParameters(writer, cycle);
070        
071        writer.closeTag();
072
073        renderDelegateSuffix(writer, cycle);
074    }
075
076    /**
077     * @see org.apache.tapestry.form.AbstractFormComponent#rewindFormComponent(org.apache.tapestry.IMarkupWriter,
078     *      org.apache.tapestry.IRequestCycle)
079     */
080    protected void rewindFormComponent(IMarkupWriter writer, IRequestCycle cycle)
081    {
082        IUploadFile file = getDecoder().getFileUpload(getName());
083        
084        if (HiveMind.isBlank(file.getFileName()))
085        {
086            file = null;
087        }
088        
089        try
090        {
091            getValidatableFieldSupport().validate(this, writer, cycle, file);
092            
093            setFile(file);
094        }
095        catch (ValidatorException e)
096        {
097            getForm().getDelegate().record(e);
098        }
099    }
100    
101    /**
102     * Injected.
103     */
104    public abstract ValidatableFieldSupport getValidatableFieldSupport();
105
106    /**
107     * Injected.
108     */
109    public abstract MultipartDecoder getDecoder();
110
111    /**
112     * @see org.apache.tapestry.form.AbstractFormComponent#isRequired()
113     */
114    public boolean isRequired()
115    {
116        return getValidatableFieldSupport().isRequired(this);
117    }
118}