Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You 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.commons.fileupload.disk; import java.io.File; import org.apache.commons.fileupload.FileItem; import org.apache.commons.fileupload.FileItemFactory; import org.apache.commons.io.FileCleaningTracker; /** * <p>The default {@link org.apache.commons.fileupload.FileItemFactory} * implementation. This implementation creates * {@link org.apache.commons.fileupload.FileItem} instances which keep their * content either in memory, for smaller items, or in a temporary file on disk, * for larger items. The size threshold, above which content will be stored on * disk, is configurable, as is the directory in which temporary files will be * created.</p> * * <p>If not otherwise configured, the default configuration values are as * follows: * <ul> * <li>Size threshold is 10KB.</li> * <li>Repository is the system default temp directory, as returned by * <code>System.getProperty("java.io.tmpdir")</code>.</li> * </ul> * </p> * * <p>When using the <code>DiskFileItemFactory</code>, then you should * consider the following: Temporary files are automatically deleted as * soon as they are no longer needed. (More precisely, when the * corresponding instance of {@link java.io.File} is garbage collected.) * Cleaning up those files is done by an instance of * {@link FileCleaningTracker}, and an associated thread. In a complex * environment, for example in a web application, you should consider * terminating this thread, for example, when your web application * ends. See the section on "Resource cleanup" * in the users guide of commons-fileupload.</p> * * @author <a href="mailto:martinc@apache.org">Martin Cooper</a> * * @since FileUpload 1.1 * * @version $Id: DiskFileItemFactory.java 607869 2008-01-01 16:42:17Z jochen $ */ public class DiskFileItemFactory implements FileItemFactory { // ----------------------------------------------------- Manifest constants /** * The default threshold above which uploads will be stored on disk. */ public static final int DEFAULT_SIZE_THRESHOLD = 10240; // ----------------------------------------------------- Instance Variables /** * The directory in which uploaded files will be stored, if stored on disk. */ private File repository; /** * The threshold above which uploads will be stored on disk. */ private int sizeThreshold = DEFAULT_SIZE_THRESHOLD; /** * <p>The instance of {@link FileCleaningTracker}, which is responsible * for deleting temporary files.</p> * <p>May be null, if tracking files is not required.</p> */ private FileCleaningTracker fileCleaningTracker; // ----------------------------------------------------------- Constructors /** * Constructs an unconfigured instance of this class. The resulting factory * may be configured by calling the appropriate setter methods. */ public DiskFileItemFactory() { this(DEFAULT_SIZE_THRESHOLD, null); } /** * Constructs a preconfigured instance of this class. * * @param sizeThreshold The threshold, in bytes, below which items will be * retained in memory and above which they will be * stored as a file. * @param repository The data repository, which is the directory in * which files will be created, should the item size * exceed the threshold. */ public DiskFileItemFactory(int sizeThreshold, File repository) { this.sizeThreshold = sizeThreshold; this.repository = repository; } // ------------------------------------------------------------- Properties /** * Returns the directory used to temporarily store files that are larger * than the configured size threshold. * * @return The directory in which temporary files will be located. * * @see #setRepository(java.io.File) * */ public File getRepository() { return repository; } /** * Sets the directory used to temporarily store files that are larger * than the configured size threshold. * * @param repository The directory in which temporary files will be located. * * @see #getRepository() * */ public void setRepository(File repository) { this.repository = repository; } /** * Returns the size threshold beyond which files are written directly to * disk. The default value is 10240 bytes. * * @return The size threshold, in bytes. * * @see #setSizeThreshold(int) */ public int getSizeThreshold() { return sizeThreshold; } /** * Sets the size threshold beyond which files are written directly to disk. * * @param sizeThreshold The size threshold, in bytes. * * @see #getSizeThreshold() * */ public void setSizeThreshold(int sizeThreshold) { this.sizeThreshold = sizeThreshold; } // --------------------------------------------------------- Public Methods /** * Create a new {@link org.apache.commons.fileupload.disk.DiskFileItem} * instance from the supplied parameters and the local factory * configuration. * * @param fieldName The name of the form field. * @param contentType The content type of the form field. * @param isFormField <code>true</code> if this is a plain form field; * <code>false</code> otherwise. * @param fileName The name of the uploaded file, if any, as supplied * by the browser or other client. * * @return The newly created file item. */ public FileItem createItem(String fieldName, String contentType, boolean isFormField, String fileName) { DiskFileItem result = new DiskFileItem(fieldName, contentType, isFormField, fileName, sizeThreshold, repository); FileCleaningTracker tracker = getFileCleaningTracker(); if (tracker != null) { tracker.track(result.getTempFile(), this); } return result; } /** * Returns the tracker, which is responsible for deleting temporary * files. * @return An instance of {@link FileCleaningTracker}, defaults to * {@link org.apache.commons.io.FileCleaner#getInstance()}. Null, * if temporary files aren't tracked. */ public FileCleaningTracker getFileCleaningTracker() { return fileCleaningTracker; } /** * Returns the tracker, which is responsible for deleting temporary * files. * @param pTracker An instance of {@link FileCleaningTracker}, * which will from now on track the created files. May be null * to disable tracking. */ public void setFileCleaningTracker(FileCleaningTracker pTracker) { fileCleaningTracker = pTracker; } }