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    
015    package org.apache.tapestry.form;
016    
017    import org.apache.hivemind.HiveMind;
018    import org.apache.tapestry.IForm;
019    import org.apache.tapestry.IMarkupWriter;
020    import org.apache.tapestry.IRequestCycle;
021    import org.apache.tapestry.multipart.MultipartDecoder;
022    import org.apache.tapestry.request.IUploadFile;
023    import 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    
037    public 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 (file != null && 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    }