fileuploadbase.java

实现上传功能的

    public FileItemIterator getItemIterator(RequestContext ctx)
    throws FileUploadException, IOException {
        return new FileItemIteratorImpl(ctx);
    }

    /**
     * Processes an <a href="http://www.ietf.org/rfc/rfc1867.txt">RFC 1867</a>
     * compliant <code>multipart/form-data</code> stream.
     *
     * @param ctx The context for the request to be parsed.
     *
     * @return A list of <code>FileItem</code> instances parsed from the
     *         request, in the order that they were transmitted.
     *
     * @throws FileUploadException if there are problems reading/parsing
     *                             the request or storing files.
     */
    public List /* FileItem */ parseRequest(RequestContext ctx)
            throws FileUploadException {
        try {
            FileItemIterator iter = getItemIterator(ctx);
            List items = new ArrayList();
            FileItemFactory fac = getFileItemFactory();
            if (fac == null) {
                throw new NullPointerException(
                    "No FileItemFactory has been set.");
            }
            while (iter.hasNext()) {
                FileItemStream item = iter.next();
                FileItem fileItem = fac.createItem(item.getFieldName(),
                        item.getContentType(), item.isFormField(),
                        item.getName());
                try {
                    Streams.copy(item.openStream(), fileItem.getOutputStream(),
                            true);
                } catch (FileUploadIOException e) {
                    throw (FileUploadException) e.getCause();
                } catch (IOException e) {
                    throw new IOFileUploadException(
                            "Processing of " + MULTIPART_FORM_DATA
                            + " request failed. " + e.getMessage(), e);
                }
                if (fileItem instanceof FileItemHeadersSupport) {
                    final FileItemHeaders fih = item.getHeaders();
                    ((FileItemHeadersSupport) fileItem).setHeaders(fih);
                }
                items.add(fileItem);
            }
            return items;
        } catch (FileUploadIOException e) {
            throw (FileUploadException) e.getCause();
        } catch (IOException e) {
            throw new FileUploadException(e.getMessage(), e);
        }
    }


    // ------------------------------------------------------ Protected methods


    /**
     * Retrieves the boundary from the <code>Content-type</code> header.
     *
     * @param contentType The value of the content type header from which to
     *                    extract the boundary value.
     *
     * @return The boundary, as a byte array.
     */
    protected byte[] getBoundary(String contentType) {
        ParameterParser parser = new ParameterParser();
        parser.setLowerCaseNames(true);
        // Parameter parser can handle null input
        Map params = parser.parse(contentType, new char[] {';', ','});
        String boundaryStr = (String) params.get("boundary");

        if (boundaryStr == null) {
            return null;
        }
        byte[] boundary;
        try {
            boundary = boundaryStr.getBytes("ISO-8859-1");
        } catch (UnsupportedEncodingException e) {
            boundary = boundaryStr.getBytes();
        }
        return boundary;
    }


    /**
     * Retrieves the file name from the <code>Content-disposition</code>
     * header.
     *
     * @param headers A <code>Map</code> containing the HTTP request headers.
     *
     * @return The file name for the current <code>encapsulation</code>.
     * @deprecated Use {@link #getFileName(FileItemHeaders)}.
     */
    protected String getFileName(Map /* String, String */ headers) {
        return getFileName(getHeader(headers, CONTENT_DISPOSITION));
    }

    /**
     * Retrieves the file name from the <code>Content-disposition</code>
     * header.
     *
     * @param headers The HTTP headers object.
     *
     * @return The file name for the current <code>encapsulation</code>.
     */
    protected String getFileName(FileItemHeaders headers) {
        return getFileName(headers.getHeader(CONTENT_DISPOSITION));
    }

    /**
     * Returns the given content-disposition headers file name.
     * @param pContentDisposition The content-disposition headers value.
     * @return The file name
     */
    private String getFileName(String pContentDisposition) {
        String fileName = null;
        if (pContentDisposition != null) {
            String cdl = pContentDisposition.toLowerCase();
            if (cdl.startsWith(FORM_DATA) || cdl.startsWith(ATTACHMENT)) {
                ParameterParser parser = new ParameterParser();
                parser.setLowerCaseNames(true);
                // Parameter parser can handle null input
                Map params = parser.parse(pContentDisposition, ';');
                if (params.containsKey("filename")) {
                    fileName = (String) params.get("filename");
                    if (fileName != null) {
                        fileName = fileName.trim();
                    } else {
                        // Even if there is no value, the parameter is present,
                        // so we return an empty file name rather than no file
                        // name.
                        fileName = "";
                    }
                }
            }
        }
        return fileName;
    }


    /**
     * Retrieves the field name from the <code>Content-disposition</code>
     * header.
     *
     * @param headers A <code>Map</code> containing the HTTP request headers.
     *
     * @return The field name for the current <code>encapsulation</code>.
     */
    protected String getFieldName(FileItemHeaders headers) {
        return getFieldName(headers.getHeader(CONTENT_DISPOSITION));
    }

    /**
     * Returns the field name, which is given by the content-disposition
     * header.
     * @param pContentDisposition The content-dispositions header value.
     * @return The field jake
     */
    private String getFieldName(String pContentDisposition) {
        String fieldName = null;
        if (pContentDisposition != null
                && pContentDisposition.toLowerCase().startsWith(FORM_DATA)) {
            ParameterParser parser = new ParameterParser();
            parser.setLowerCaseNames(true);
            // Parameter parser can handle null input
            Map params = parser.parse(pContentDisposition, ';');
            fieldName = (String) params.get("name");
            if (fieldName != null) {
                fieldName = fieldName.trim();
            }
        }
        return fieldName;
    }

    /**
     * Retrieves the field name from the <code>Content-disposition</code>
     * header.
     *
     * @param headers A <code>Map</code> containing the HTTP request headers.
     *
     * @return The field name for the current <code>encapsulation</code>.
     * @deprecated Use {@link #getFieldName(FileItemHeaders)}.
     */
    protected String getFieldName(Map /* String, String */ headers) {
        return getFieldName(getHeader(headers, CONTENT_DISPOSITION));
    }


    /**
     * Creates a new {@link FileItem} instance.
     *
     * @param headers       A <code>Map</code> containing the HTTP request
     *                      headers.
     * @param isFormField   Whether or not this item is a form field, as
     *                      opposed to a file.
     *
     * @return A newly created <code>FileItem</code> instance.
     *
     * @throws FileUploadException if an error occurs.
     * @deprecated This method is no longer used in favour of
     *   internally created instances of {@link FileItem}.
     */
    protected FileItem createItem(Map /* String, String */ headers,
                                  boolean isFormField)
        throws FileUploadException {
        return getFileItemFactory().createItem(getFieldName(headers),
                getHeader(headers, CONTENT_TYPE),
                isFormField,
                getFileName(headers));
    }

    /**
     * <p> Parses the <code>header-part</code> and returns as key/value
     * pairs.
     *
     * <p> If there are multiple headers of the same names, the name
     * will map to a comma-separated list containing the values.
     *
     * @param headerPart The <code>header-part</code> of the current
     *                   <code>encapsulation</code>.
     *
     * @return A <code>Map</code> containing the parsed HTTP request headers.
     */
    protected FileItemHeaders getParsedHeaders(String headerPart) {
        final int len = headerPart.length();
        FileItemHeadersImpl headers = newFileItemHeaders();
        int start = 0;
        for (;;) {
            int end = parseEndOfLine(headerPart, start);
            if (start == end) {
                break;
            }
            String header = headerPart.substring(start, end);
            start = end + 2;
            while (start < len) {
                int nonWs = start;
                while (nonWs < len) {
                    char c = headerPart.charAt(nonWs);
                    if (c != ' '  &&  c != '\t') {
                        break;
                    }
                    ++nonWs;
                }
                if (nonWs == start) {
                    break;
                }
                // Continuation line found
                end = parseEndOfLine(headerPart, nonWs);
                header += " " + headerPart.substring(nonWs, end);
                start = end + 2;
            }
            parseHeaderLine(headers, header);
        }
        return headers;
    }

    /**
     * Creates a new instance of {@link FileItemHeaders}.
     * @return The new instance.
     */
    protected FileItemHeadersImpl newFileItemHeaders() {
        return new FileItemHeadersImpl();
    }

    /**
     * <p> Parses the <code>header-part</code> and returns as key/value
     * pairs.
     *
     * <p> If there are multiple headers of the same names, the name
     * will map to a comma-separated list containing the values.
     *
     * @param headerPart The <code>header-part</code> of the current
     *                   <code>encapsulation</code>.
     *
     * @return A <code>Map</code> containing the parsed HTTP request headers.
     * @deprecated Use {@link #getParsedHeaders(String)}
     */
    protected Map /* String, String */ parseHeaders(String headerPart) {
        FileItemHeaders headers = getParsedHeaders(headerPart);
        Map result = new HashMap();
        for (Iterator iter = headers.getHeaderNames();  iter.hasNext();) {
            String headerName = (String) iter.next();
            Iterator iter2 = headers.getHeaders(headerName);
            String headerValue = (String) iter2.next();
            while (iter2.hasNext()) {
                headerValue += "," + iter2.next();
            }
            result.put(headerName, headerValue);
        }
        return result;
    }

    /**
     * Skips bytes until the end of the current line.
     * @param headerPart The headers, which are being parsed.
     * @param end Index of the last byte, which has yet been
     *   processed.
     * @return Index of the \r\n sequence, which indicates
     *   end of line.
     */
    private int parseEndOfLine(String headerPart, int end) {
        int index = end;
        for (;;) {
            int offset = headerPart.indexOf('\r', index);
            if (offset == -1  ||  offset + 1 >= headerPart.length()) {
                throw new IllegalStateException(
                    "Expected headers to be terminated by an empty line.");
            }
            if (headerPart.charAt(offset + 1) == '\n') {
                return offset;
            }
            index = offset + 1;
        }
    }

    /**
     * Reads the next header line.
     * @param headers String with all headers.
     * @param header Map where to store the current header.
     */
    private void parseHeaderLine(FileItemHeadersImpl headers, String header) {
        final int colonOffset = header.indexOf(':');
        if (colonOffset == -1) {
            // This header line is malformed, skip it.