FileItemIteratorImpl.java
/*
* 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.tomcat.util.http.fileupload.impl;
import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.List;
import java.util.Locale;
import java.util.NoSuchElementException;
import java.util.Objects;
import org.apache.tomcat.util.http.fileupload.FileItem;
import org.apache.tomcat.util.http.fileupload.FileItemHeaders;
import org.apache.tomcat.util.http.fileupload.FileItemIterator;
import org.apache.tomcat.util.http.fileupload.FileItemStream;
import org.apache.tomcat.util.http.fileupload.FileUploadBase;
import org.apache.tomcat.util.http.fileupload.FileUploadException;
import org.apache.tomcat.util.http.fileupload.IOUtils;
import org.apache.tomcat.util.http.fileupload.MultipartStream;
import org.apache.tomcat.util.http.fileupload.ProgressListener;
import org.apache.tomcat.util.http.fileupload.RequestContext;
import org.apache.tomcat.util.http.fileupload.UploadContext;
import org.apache.tomcat.util.http.fileupload.util.LimitedInputStream;
/**
* The iterator, which is returned by
* {@link FileUploadBase#getItemIterator(RequestContext)}.
*/
public class FileItemIteratorImpl implements FileItemIterator {
/**
* The file uploads processing utility.
* @see FileUploadBase
*/
private final FileUploadBase fileUploadBase;
/**
* The request context.
* @see RequestContext
*/
private final RequestContext ctx;
/**
* The maximum allowed size of a complete request.
*/
private long sizeMax;
/**
* The maximum allowed size of a single uploaded file.
*/
private long fileSizeMax;
@Override
public long getSizeMax() {
return sizeMax;
}
@Override
public void setSizeMax(final long sizeMax) {
this.sizeMax = sizeMax;
}
@Override
public long getFileSizeMax() {
return fileSizeMax;
}
@Override
public void setFileSizeMax(final long fileSizeMax) {
this.fileSizeMax = fileSizeMax;
}
/**
* The multi part stream to process.
*/
private MultipartStream multiPartStream;
/**
* The notifier, which used for triggering the
* {@link ProgressListener}.
*/
private MultipartStream.ProgressNotifier progressNotifier;
/**
* The boundary, which separates the various parts.
*/
private byte[] multiPartBoundary;
/**
* The item, which we currently process.
*/
private FileItemStreamImpl currentItem;
/**
* The current items field name.
*/
private String currentFieldName;
/**
* Whether we are currently skipping the preamble.
*/
private boolean skipPreamble;
/**
* Whether the current item may still be read.
*/
private boolean itemValid;
/**
* Whether we have seen the end of the file.
*/
private boolean eof;
/**
* Creates a new instance.
*
* @param fileUploadBase Main processor.
* @param requestContext The request context.
* @throws FileUploadException An error occurred while
* parsing the request.
* @throws IOException An I/O error occurred.
*/
public FileItemIteratorImpl(final FileUploadBase fileUploadBase, final RequestContext requestContext)
throws FileUploadException, IOException {
this.fileUploadBase = fileUploadBase;
sizeMax = fileUploadBase.getSizeMax();
fileSizeMax = fileUploadBase.getFileSizeMax();
ctx = Objects.requireNonNull(requestContext, "requestContext");
skipPreamble = true;
findNextItem();
}
protected void init(final FileUploadBase fileUploadBase, @SuppressWarnings("unused") final RequestContext pRequestContext)
throws FileUploadException, IOException {
final String contentType = ctx.getContentType();
if ((null == contentType)
|| (!contentType.toLowerCase(Locale.ENGLISH).startsWith(FileUploadBase.MULTIPART))) {
throw new InvalidContentTypeException(
String.format("the request doesn't contain a %s or %s stream, content type header is %s",
FileUploadBase.MULTIPART_FORM_DATA, FileUploadBase.MULTIPART_MIXED, contentType));
}
final long requestSize = ((UploadContext) ctx).contentLength();
final InputStream input; // N.B. this is eventually closed in MultipartStream processing
if (sizeMax >= 0) {
if (requestSize != -1 && requestSize > sizeMax) {
throw new SizeLimitExceededException(
String.format("the request was rejected because its size (%s) exceeds the configured maximum (%s)",
Long.valueOf(requestSize), Long.valueOf(sizeMax)),
requestSize, sizeMax);
}
// N.B. this is eventually closed in MultipartStream processing
input = new LimitedInputStream(ctx.getInputStream(), sizeMax) {
@Override
protected void raiseError(final long pSizeMax, final long pCount)
throws IOException {
final FileUploadException ex = new SizeLimitExceededException(
String.format("the request was rejected because its size (%s) exceeds the configured maximum (%s)",
Long.valueOf(pCount), Long.valueOf(pSizeMax)),
pCount, pSizeMax);
throw new FileUploadIOException(ex);
}
};
} else {
input = ctx.getInputStream();
}
String charEncoding = fileUploadBase.getHeaderEncoding();
if (charEncoding == null) {
charEncoding = ctx.getCharacterEncoding();
}
multiPartBoundary = fileUploadBase.getBoundary(contentType);
if (multiPartBoundary == null) {
IOUtils.closeQuietly(input); // avoid possible resource leak
throw new FileUploadException("the request was rejected because no multipart boundary was found");
}
progressNotifier = new MultipartStream.ProgressNotifier(fileUploadBase.getProgressListener(), requestSize);
try {
multiPartStream = new MultipartStream(input, multiPartBoundary, progressNotifier);
} catch (final IllegalArgumentException iae) {
IOUtils.closeQuietly(input); // avoid possible resource leak
throw new InvalidContentTypeException(
String.format("The boundary specified in the %s header is too long", FileUploadBase.CONTENT_TYPE), iae);
}
multiPartStream.setHeaderEncoding(charEncoding);
}
public MultipartStream getMultiPartStream() throws FileUploadException, IOException {
if (multiPartStream == null) {
init(fileUploadBase, ctx);
}
return multiPartStream;
}
/**
* Called for finding the next item, if any.
*
* @return True, if an next item was found, otherwise false.
* @throws IOException An I/O error occurred.
*/
private boolean findNextItem() throws FileUploadException, IOException {
if (eof) {
return false;
}
if (currentItem != null) {
currentItem.close();
currentItem = null;
}
final MultipartStream multi = getMultiPartStream();
for (;;) {
final boolean nextPart;
if (skipPreamble) {
nextPart = multi.skipPreamble();
} else {
nextPart = multi.readBoundary();
}
if (!nextPart) {
if (currentFieldName == null) {
// Outer multipart terminated -> No more data
eof = true;
return false;
}
// Inner multipart terminated -> Return to parsing the outer
multi.setBoundary(multiPartBoundary);
currentFieldName = null;
continue;
}
final FileItemHeaders headers = fileUploadBase.getParsedHeaders(multi.readHeaders());
if (currentFieldName == null) {
// We're parsing the outer multipart
final String fieldName = fileUploadBase.getFieldName(headers);
if (fieldName != null) {
final String subContentType = headers.getHeader(FileUploadBase.CONTENT_TYPE);
if (subContentType != null
&& subContentType.toLowerCase(Locale.ENGLISH)
.startsWith(FileUploadBase.MULTIPART_MIXED)) {
currentFieldName = fieldName;
// Multiple files associated with this field name
final byte[] subBoundary = fileUploadBase.getBoundary(subContentType);
multi.setBoundary(subBoundary);
skipPreamble = true;
continue;
}
final String fileName = fileUploadBase.getFileName(headers);
currentItem = new FileItemStreamImpl(this, fileName,
fieldName, headers.getHeader(FileUploadBase.CONTENT_TYPE),
fileName == null, getContentLength(headers));
currentItem.setHeaders(headers);
progressNotifier.noteItem();
itemValid = true;
return true;
}
} else {
final String fileName = fileUploadBase.getFileName(headers);
if (fileName != null) {
currentItem = new FileItemStreamImpl(this, fileName,
currentFieldName,
headers.getHeader(FileUploadBase.CONTENT_TYPE),
false, getContentLength(headers));
currentItem.setHeaders(headers);
progressNotifier.noteItem();
itemValid = true;
return true;
}
}
multi.discardBodyData();
}
}
private long getContentLength(final FileItemHeaders pHeaders) {
try {
return Long.parseLong(pHeaders.getHeader(FileUploadBase.CONTENT_LENGTH));
} catch (final Exception e) {
return -1;
}
}
/**
* Returns, whether another instance of {@link FileItemStream}
* is available.
*
* @throws FileUploadException Parsing or processing the
* file item failed.
* @throws IOException Reading the file item failed.
* @return True, if one or more additional file items
* are available, otherwise false.
*/
@Override
public boolean hasNext() throws FileUploadException, IOException {
if (eof) {
return false;
}
if (itemValid) {
return true;
}
try {
return findNextItem();
} catch (final FileUploadIOException e) {
// unwrap encapsulated SizeException
throw (FileUploadException) e.getCause();
}
}
/**
* Returns the next available {@link FileItemStream}.
*
* @throws java.util.NoSuchElementException No more items are
* available. Use {@link #hasNext()} to prevent this exception.
* @throws FileUploadException Parsing or processing the
* file item failed.
* @throws IOException Reading the file item failed.
* @return FileItemStream instance, which provides
* access to the next file item.
*/
@Override
public FileItemStream next() throws FileUploadException, IOException {
if (eof || (!itemValid && !hasNext())) {
throw new NoSuchElementException();
}
itemValid = false;
return currentItem;
}
@Override
public List<FileItem> getFileItems() throws FileUploadException, IOException {
final List<FileItem> items = new ArrayList<>();
while (hasNext()) {
final FileItemStream fis = next();
final FileItem fi = fileUploadBase.getFileItemFactory().createItem(fis.getFieldName(),
fis.getContentType(), fis.isFormField(), fis.getName());
items.add(fi);
}
return items;
}
}