easyJ.http.upload.CommonsMultipartRequestHandler.java Source code

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/*
 * $Header:
 * /EasyJ/EasyJ/src/easyJ/http/upload/CommonsMultipartRequestHandler.java,v
 * 1.1.1.1 2008/05/12 09:53:38 guanly Exp $ $Revision: 1.1.1.1 $ $Date:
 * 2008/05/12 09:53:38 $
 * ==================================================================== The
 * Apache Software License, Version 1.1 Copyright (c) 1999-2002 The Apache
 * Software Foundation. All rights reserved. Redistribution and use in source
 * and binary forms, with or without modification, are permitted provided that
 * the following conditions are met: 1. Redistributions of source code must
 * retain the above copyright notice, this list of conditions and the following
 * disclaimer. 2. Redistributions in binary form must reproduce the above
 * copyright notice, this list of conditions and the following disclaimer in the
 * documentation and/or other materials provided with the distribution. 3. The
 * end-user documentation included with the redistribution, if any, must include
 * the following acknowlegement: "This product includes software developed by
 * the Apache Software Foundation (http://www.apache.org/)." Alternately, this
 * acknowlegement may appear in the software itself, if and wherever such
 * third-party acknowlegements normally appear. 4. The names "The Jakarta
 * Project", "Struts", and "Apache Software Foundation" must not be used to
 * endorse or promote products derived from this software without prior written
 * permission. For written permission, please contact apache@apache.org. 5.
 * Products derived from this software may not be called "Apache" nor may
 * "Apache" appear in their names without prior written permission of the Apache
 * Group. THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
 * EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR ITS CONTRIBUTORS BE LIABLE FOR
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * ==================================================================== This
 * software consists of voluntary contributions made by many individuals on
 * behalf of the Apache Software Foundation. For more information on the Apache
 * Software Foundation, please see <http://www.apache.org/>.
 */

package easyJ.http.upload;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.InputStream;
import java.io.IOException;
import java.util.Hashtable;
import java.util.Iterator;
import java.util.List;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.DiskFileUpload;
import org.apache.commons.fileupload.FileUploadException;
import easyJ.logging.Log;
import easyJ.logging.LogFactory;
import easyJ.http.config.ModuleConfig;
import easyJ.http.Globals;
import javax.servlet.http.HttpServlet;
import easyJ.logging.EasyJLog;

/**
 * This class implements the <code>MultipartRequestHandler</code> interface by
 * providing a wrapper around the Jakarta Commons FileUpload library.
 * 
 * @author Martin Cooper
 * @version $Revision: 1.1.1.1 $ $Date: 2008/05/12 09:53:38 $
 * @since Struts 1.1
 */
public class CommonsMultipartRequestHandler implements MultipartRequestHandler {

    // ----------------------------------------------------- Manifest Constants

    /**
     * The default value for the maximum allowable size, in bytes, of an
     * uploaded file. The value is equivalent to 250MB.
     */
    public static final long DEFAULT_SIZE_MAX = 250 * 1024 * 1024;

    /**
     * The default value for the threshold which determines whether an uploaded
     * file will be written to disk or cached in memory. The value is equivalent
     * to 250KB.
     */
    public static final int DEFAULT_SIZE_THRESHOLD = 256 * 1024;

    // ----------------------------------------------------- Instance Variables

    /**
     * Commons Logging instance.
     */
    // protected static Log log = LogFactory.getLog();

    /**
     * The combined text and file request parameters.
     */
    private Hashtable elementsAll;

    /**
     * The file request parameters.
     */
    private Hashtable elementsFile;

    /**
     * The text request parameters.
     */
    private Hashtable elementsText;

    /**
     * The action mapping with which this handler is associated.
     */

    /**
     * The servlet with which this handler is associated.
     */
    private HttpServlet servlet;

    // ---------------------------------------- MultipartRequestHandler Methods

    /**
     * Retrieves the servlet with which this handler is associated.
     * 
     * @return The associated servlet.
     */
    public HttpServlet getServlet() {
        return this.servlet;
    }

    /**
     * Sets the servlet with which this handler is associated.
     * 
     * @param servlet
     *                The associated servlet.
     */
    public void setServlet(HttpServlet servlet) {
        this.servlet = servlet;
    }

    /**
     * Retrieves the action mapping with which this handler is associated.
     * 
     * @return The associated action mapping.
     */

    /**
     * Sets the action mapping with which this handler is associated.
     * 
     * @param mapping
     *                The associated action mapping.
     */

    /**
     * Parses the input stream and partitions the parsed items into a set of
     * form fields and a set of file items. In the process, the parsed items are
     * translated from Commons FileUpload <code>FileItem</code> instances to
     * Struts <code>FormFile</code> instances.
     * 
     * @param request
     *                The multipart request to be processed.
     * @throws ServletException
     *                 if an unrecoverable error occurs.
     */
    public void handleRequest(HttpServletRequest request) throws ServletException {

        // Get the app config for the current request.
        ModuleConfig ac = (ModuleConfig) request.getAttribute(Globals.MODULE_KEY);

        // Create and configure a DIskFileUpload instance.
        DiskFileUpload upload = new DiskFileUpload();
        // Set the maximum size before a FileUploadException will be thrown.
        upload.setSizeMax((int) getSizeMax(ac));
        // Set the maximum size that will be stored in memory.
        upload.setSizeThreshold((int) getSizeThreshold(ac));
        // Set the the location for saving data on disk.
        upload.setRepositoryPath(getRepositoryPath(ac));

        // Create the hash tables to be populated.
        elementsText = new Hashtable();
        elementsFile = new Hashtable();
        elementsAll = new Hashtable();

        // Parse the request into file items.
        List items = null;
        try {
            items = upload.parseRequest(request);
        } catch (DiskFileUpload.SizeLimitExceededException e) {
            // Special handling for uploads that are too big.
            request.setAttribute(MultipartRequestHandler.ATTRIBUTE_MAX_LENGTH_EXCEEDED, Boolean.TRUE);
            return;
        } catch (FileUploadException e) {
            EasyJLog.error("Failed to parse multipart request", e);
            throw new ServletException(e);
        }

        // Partition the items into form fields and files.
        Iterator iter = items.iterator();
        while (iter.hasNext()) {
            FileItem item = (FileItem) iter.next();

            if (item.isFormField()) {
                addTextParameter(request, item);
            } else {
                addFileParameter(item);
            }
        }
    }

    /**
     * Returns a hash table containing the text (that is, non-file) request
     * parameters.
     * 
     * @return The text request parameters.
     */
    public Hashtable getTextElements() {
        return this.elementsText;
    }

    /**
     * Returns a hash table containing the file (that is, non-text) request
     * parameters.
     * 
     * @return The file request parameters.
     */
    public Hashtable getFileElements() {
        return this.elementsFile;
    }

    /**
     * Returns a hash table containing both text and file request parameters.
     * 
     * @return The text and file request parameters.
     */
    public Hashtable getAllElements() {
        return this.elementsAll;
    }

    /**
     * Cleans up when a problem occurs during request processing.
     */
    public void rollback() {
        Iterator iter = elementsFile.values().iterator();

        while (iter.hasNext()) {
            FormFile formFile = (FormFile) iter.next();

            formFile.destroy();
        }
    }

    /**
     * Cleans up at the end of a request.
     */
    public void finish() {
        rollback();
    }

    // -------------------------------------------------------- Support Methods

    /**
     * Returns the maximum allowable size, in bytes, of an uploaded file. The
     * value is obtained from the current module's controller configuration.
     * 
     * @param mc
     *                The current module's configuration.
     * @return The maximum allowable file size, in bytes.
     */
    protected long getSizeMax(ModuleConfig mc) {
        return convertSizeToBytes(mc.getControllerConfig().getMaxFileSize(), DEFAULT_SIZE_MAX);
    }

    /**
     * Returns the size threshold which determines whether an uploaded file will
     * be written to disk or cached in memory.
     * 
     * @param mc
     *                The current module's configuration.
     * @return The size threshold, in bytes.
     */
    protected long getSizeThreshold(ModuleConfig mc) {
        return convertSizeToBytes(mc.getControllerConfig().getMemFileSize(), DEFAULT_SIZE_THRESHOLD);
    }

    /**
     * Converts a size value from a string representation to its numeric value.
     * The string must be of the form nnnm, where nnn is an arbitrary decimal
     * value, and m is a multiplier. The multiplier must be one of 'K', 'M' and
     * 'G', representing kilobytes, megabytes and gigabytes respectively. If the
     * size value cannot be converted, for example due to invalid syntax, the
     * supplied default is returned instead.
     * 
     * @param sizeString
     *                The string representation of the size to be converted.
     * @param defaultSize
     *                The value to be returned if the string is invalid.
     * @return The actual size in bytes.
     */
    protected long convertSizeToBytes(String sizeString, long defaultSize) {
        int multiplier = 1;

        if (sizeString.endsWith("K")) {
            multiplier = 1024;
        } else if (sizeString.endsWith("M")) {
            multiplier = 1024 * 1024;
        } else if (sizeString.endsWith("G")) {
            multiplier = 1024 * 1024 * 1024;
        }
        if (multiplier != 1) {
            sizeString = sizeString.substring(0, sizeString.length() - 1);
        }

        long size = 0;
        try {
            size = Long.parseLong(sizeString);
        } catch (NumberFormatException nfe) {
            EasyJLog.warn("Invalid format for file size ('" + sizeString + "'). Using default.");
            size = defaultSize;
            multiplier = 1;
        }

        return (size * multiplier);
    }

    /**
     * Returns the path to the temporary directory to be used for uploaded files
     * which are written to disk. The directory used is determined from the
     * first of the following to be non-empty.
     * <ol>
     * <li>A temp dir explicitly defined either using the <code>tempDir</code>
     * servlet init param, or the <code>tempDir</code> attribute of the
     * &lt;controller&gt; element in the Struts config file.</li>
     * <li>The container-specified temp dir, obtained from the
     * <code>javax.servlet.context.tempdir</code> servlet context attribute.</li>
     * <li>The temp dir specified by the <code>java.io.tmpdir</code> system
     * property.</li>
     * (/ol>
     * 
     * @param mc
     *                The module config instance for which the path should be
     *                determined.
     * @return The path to the directory to be used to store uploaded files.
     */
    protected String getRepositoryPath(ModuleConfig mc) {

        // First, look for an explicitly defined temp dir.
        String tempDir = mc.getControllerConfig().getTempDir();

        // If none, look for a container specified temp dir.
        if (tempDir == null || tempDir.length() == 0) {
            if (servlet != null) {
                ServletContext context = servlet.getServletContext();
                File tempDirFile = (File) context.getAttribute("javax.servlet.context.tempdir");
                tempDir = tempDirFile.getAbsolutePath();
            }

            // If none, pick up the system temp dir.
            if (tempDir == null || tempDir.length() == 0) {
                tempDir = System.getProperty("java.io.tmpdir");
            }
        }

        return tempDir;
    }

    /**
     * Adds a regular text parameter to the set of text parameters for this
     * request and also to the list of all parameters. Handles the case of
     * multiple values for the same parameter by using an array for the
     * parameter value.
     * 
     * @param request
     *                The request in which the parameter was specified.
     * @param item
     *                The file item for the parameter to add.
     */
    protected void addTextParameter(HttpServletRequest request, FileItem item) {
        String name = item.getFieldName();
        String value = null;

        try {
            value = item.getString(request.getCharacterEncoding());
        } catch (Exception e) {
            value = item.getString();
        }

        if (request instanceof MultipartRequestWrapper) {
            MultipartRequestWrapper wrapper = (MultipartRequestWrapper) request;
            wrapper.setParameter(name, value);
        }

        String[] oldArray = (String[]) elementsText.get(name);
        String[] newArray;

        if (oldArray != null) {
            newArray = new String[oldArray.length + 1];
            System.arraycopy(oldArray, 0, newArray, 0, oldArray.length);
            newArray[oldArray.length] = value;
        } else {
            newArray = new String[] { value };
        }

        elementsText.put(name, newArray);
        elementsAll.put(name, newArray);
    }

    /**
     * Adds a file parameter to the set of file parameters for this request and
     * also to the list of all parameters.
     * 
     * @param item
     *                The file item for the parameter to add.
     */
    protected void addFileParameter(FileItem item) {
        FormFile formFile = new CommonsFormFile(item);

        elementsFile.put(item.getFieldName(), formFile);
        elementsAll.put(item.getFieldName(), formFile);
    }

    // ---------------------------------------------------------- Inner Classes

    /**
     * This class implements the Struts <code>FormFile</code> interface by
     * wrapping the Commons FileUpload <code>FileItem</code> interface. This
     * implementation is <i>read-only</i>; any attempt to modify an instance of
     * this class will result in an <code>UnsupportedOperationException</code>.
     */
    static class CommonsFormFile implements FormFile {

        /**
         * The <code>FileItem</code> instance wrapped by this object.
         */
        FileItem fileItem;

        /**
         * Constructs an instance of this class which wraps the supplied file
         * item.
         * 
         * @param fileItem
         *                The Commons file item to be wrapped.
         */
        public CommonsFormFile(FileItem fileItem) {
            this.fileItem = fileItem;
        }

        /**
         * Returns the content type for this file.
         * 
         * @return A String representing content type.
         */
        public String getContentType() {
            return fileItem.getContentType();
        }

        /**
         * Sets the content type for this file.
         * <p>
         * NOTE: This method is not supported in this implementation.
         * 
         * @param contentType
         *                A string representing the content type.
         */
        public void setContentType(String contentType) {
            throw new UnsupportedOperationException("The setContentType() method is not supported.");
        }

        /**
         * Returns the size, in bytes, of this file.
         * 
         * @return The size of the file, in bytes.
         */
        public int getFileSize() {
            return (int) fileItem.getSize();
        }

        /**
         * Sets the size, in bytes, for this file.
         * <p>
         * NOTE: This method is not supported in this implementation.
         * 
         * @param filesize
         *                The size of the file, in bytes.
         */
        public void setFileSize(int filesize) {
            throw new UnsupportedOperationException("The setFileSize() method is not supported.");
        }

        /**
         * Returns the (client-side) file name for this file.
         * 
         * @return The client-size file name.
         */
        public String getFileName() {
            return getBaseFileName(fileItem.getName());
        }

        /**
         * Sets the (client-side) file name for this file.
         * <p>
         * NOTE: This method is not supported in this implementation.
         * 
         * @param fileName
         *                The client-side name for the file.
         */
        public void setFileName(String fileName) {
            throw new UnsupportedOperationException("The setFileName() method is not supported.");
        }

        /**
         * Returns the data for this file as a byte array. Note that this may
         * result in excessive memory usage for large uploads. The use of the
         * {@link #getInputStream() getInputStream} method is encouraged as an
         * alternative.
         * 
         * @return An array of bytes representing the data contained in this
         *         form file.
         * @exception FileNotFoundException
         *                    If some sort of file representation cannot be
         *                    found for the FormFile
         * @exception IOException
         *                    If there is some sort of IOException
         */
        public byte[] getFileData() throws FileNotFoundException, IOException {
            return fileItem.get();
        }

        /**
         * Get an InputStream that represents this file. This is the preferred
         * method of getting file data.
         * 
         * @exception FileNotFoundException
         *                    If some sort of file representation cannot be
         *                    found for the FormFile
         * @exception IOException
         *                    If there is some sort of IOException
         */
        public InputStream getInputStream() throws FileNotFoundException, IOException {
            return fileItem.getInputStream();
        }

        /**
         * Destroy all content for this form file. Implementations should remove
         * any temporary files or any temporary file data stored somewhere
         */
        public void destroy() {
            fileItem.delete();
        }

        /**
         * Returns the base file name from the supplied file path. On the
         * surface, this would appear to be a trivial task. Apparently, however,
         * some Linux JDKs do not implement <code>File.getName()</code>
         * correctly for Windows paths, so we attempt to take care of that here.
         * 
         * @param filePath
         *                The full path to the file.
         * @return The base file name, from the end of the path.
         */
        protected String getBaseFileName(String filePath) {

            // First, ask the JDK for the base file name.
            String fileName = new File(filePath).getName();

            // Now check for a Windows file name parsed incorrectly.
            int colonIndex = fileName.indexOf(":");
            if (colonIndex == -1) {
                // Check for a Windows SMB file path.
                colonIndex = fileName.indexOf("\\\\");
            }
            int backslashIndex = fileName.lastIndexOf("\\");

            if (colonIndex > -1 && backslashIndex > -1) {
                // Consider this filename to be a full Windows path, and parse
                // it
                // accordingly to retrieve just the base file name.
                fileName = fileName.substring(backslashIndex + 1);
            }

            return fileName;
        }

        /**
         * Returns the (client-side) file name for this file.
         * 
         * @return The client-size file name.
         */
        public String toString() {
            return getFileName();
        }
    }
}