commonsmultipartrequesthandler.java

这是一个轻便的j2ee的web应用框架,是一个在多个项目中运用的实际框架,采用struts,hebinate,xml等技术,有丰富的tag,role,navigation,session,dictio

     * @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) {
            log.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");
            }
        }

        if (log.isTraceEnabled()) {
            log.trace("File upload temp dir: " + tempDir);
        }

        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();
        }
    }
}