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/*
* 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.tika.io;
import static java.nio.file.StandardCopyOption.REPLACE_EXISTING;
import java.io.BufferedInputStream;
import java.io.ByteArrayInputStream;
import java.io.Closeable;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.net.URI;
import java.net.URISyntaxException;
import java.net.URL;
import java.net.URLConnection;
import java.nio.channels.FileChannel;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.sql.Blob;
import java.sql.SQLException;
import org.apache.tika.metadata.Metadata;
/**
* Input stream with extended capabilities. The purpose of this class is
* to allow files and other resources and information to be associated with
* the {@link InputStream} instance passed through the
* {@link org.apache.tika.parser.Parser} interface and other similar APIs.
*
* TikaInputStream instances can be created using the various static
* get() factory methods. Most of these methods take an optional
* {@link Metadata} argument that is then filled with the available input
* metadata from the given resource. The created TikaInputStream instance
* keeps track of the original resource used to create it, while behaving
* otherwise just like a normal, buffered {@link InputStream}.
* A TikaInputStream instance is also guaranteed to support the
* {@link #mark(int)} feature.
*
* Code that wants to access the underlying file or other resources
* associated with a TikaInputStream should first use the
* {@link #get(InputStream)} factory method to cast or wrap a given
* {@link InputStream} into a TikaInputStream instance.
*
* @since Apache Tika 0.8
*/
public class TikaInputStream extends TaggedInputStream {
/**
* Checks whether the given stream is a TikaInputStream instance.
* The given stream can be null, in which case the return
* value is false.
*
* @param stream input stream, possibly null
* @return true if the stream is a TikaInputStream instance,
* false otherwise
*/
public static boolean isTikaInputStream(InputStream stream) {
return stream instanceof TikaInputStream;
}
/**
* Casts or wraps the given stream to a TikaInputStream instance.
* This method can be used to access the functionality of this class
* even when given just a normal input stream instance.
*
* The given temporary file provider is used for any temporary files,
* and should be disposed when the returned stream is no longer used.
*
* Use this method instead of the {@link #get(InputStream)} alternative
* when you don't explicitly close the returned stream. The
* recommended access pattern is:
*
* try (TemporaryResources tmp = new TemporaryResources()) {
* TikaInputStream stream = TikaInputStream.get(..., tmp);
* // process stream but don't close it
* }
*
*
* The given stream instance will not be closed when the
* {@link TemporaryResources#close()} method is called by the
* try-with-resources statement. The caller is expected to explicitly
* close the original stream when it's no longer used.
*
* @since Apache Tika 0.10
* @param stream normal input stream
* @return a TikaInputStream instance
*/
public static TikaInputStream get(
InputStream stream, TemporaryResources tmp) {
if (stream == null) {
throw new NullPointerException("The Stream must not be null");
}
if (stream instanceof TikaInputStream) {
return (TikaInputStream) stream;
} else {
// Make sure that the stream is buffered and that it
// (properly) supports the mark feature
if (!(stream instanceof BufferedInputStream)
&& !(stream instanceof ByteArrayInputStream)) {
stream = new BufferedInputStream(stream);
}
return new TikaInputStream(stream, tmp, -1);
}
}
/**
* Casts or wraps the given stream to a TikaInputStream instance.
* This method can be used to access the functionality of this class
* even when given just a normal input stream instance.
*
* Use this method instead of the
* {@link #get(InputStream, TemporaryResources)} alternative when you
* do explicitly close the returned stream. The recommended
* access pattern is:
*
* try (TikaInputStream stream = TikaInputStream.get(...)) {
* // process stream
* }
*
*
* The given stream instance will be closed along with any other resources
* associated with the returned TikaInputStream instance when the
* {@link #close()} method is called by the try-with-resources statement.
*
* @param stream normal input stream
* @return a TikaInputStream instance
*/
public static TikaInputStream get(InputStream stream) {
return get(stream, new TemporaryResources());
}
/**
* Returns the given stream casts to a TikaInputStream, or
* null if the stream is not a TikaInputStream.
*
* @since Apache Tika 0.10
* @param stream normal input stream
* @return a TikaInputStream instance
*/
public static TikaInputStream cast(InputStream stream) {
if (stream instanceof TikaInputStream) {
return (TikaInputStream) stream;
} else {
return null;
}
}
/**
* Creates a TikaInputStream from the given array of bytes.
*
* Note that you must always explicitly close the returned stream as in
* some cases it may end up writing the given data to a temporary file.
*
* @param data input data
* @return a TikaInputStream instance
*/
public static TikaInputStream get(byte[] data) {
return get(data, new Metadata());
}
/**
* Creates a TikaInputStream from the given array of bytes. The length of
* the array is stored as input metadata in the given metadata instance.
*
* Note that you must always explicitly close the returned stream as in
* some cases it may end up writing the given data to a temporary file.
*
* @param data input data
* @param metadata metadata instance
* @return a TikaInputStream instance
* @throws IOException
*/
public static TikaInputStream get(byte[] data, Metadata metadata) {
metadata.set(Metadata.CONTENT_LENGTH, Integer.toString(data.length));
return new TikaInputStream(
new ByteArrayInputStream(data),
new TemporaryResources(), data.length);
}
/**
* Creates a TikaInputStream from the file at the given path.
*
* Note that you must always explicitly close the returned stream to
* prevent leaking open file handles.
*
* @param path input file
* @return a TikaInputStream instance
* @throws IOException if an I/O error occurs
*/
public static TikaInputStream get(Path path) throws IOException {
return get(path, new Metadata());
}
/**
* Creates a TikaInputStream from the file at the given path. The file name
* and length are stored as input metadata in the given metadata instance.
*
* Note that you must always explicitly close the returned stream to
* prevent leaking open file handles.
*
* @param path input file
* @param metadata metadata instance
* @return a TikaInputStream instance
* @throws IOException if an I/O error occurs
*/
public static TikaInputStream get(Path path, Metadata metadata)
throws IOException {
metadata.set(Metadata.RESOURCE_NAME_KEY, path.getFileName().toString());
metadata.set(Metadata.CONTENT_LENGTH, Long.toString(Files.size(path)));
return new TikaInputStream(path);
}
/**
* Creates a TikaInputStream from the given file.
*
* Note that you must always explicitly close the returned stream to
* prevent leaking open file handles.
*
* @param file input file
* @return a TikaInputStream instance
* @throws FileNotFoundException if the file does not exist
* @deprecated use {@link #get(Path)}. In Tika 2.0, this will be removed
* or modified to throw an IOException.
*/
@Deprecated
public static TikaInputStream get(File file) throws FileNotFoundException {
return get(file, new Metadata());
}
/**
* Creates a TikaInputStream from the given file. The file name and
* length are stored as input metadata in the given metadata instance.
*
* Note that you must always explicitly close the returned stream to
* prevent leaking open file handles.
*
* @param file input file
* @param metadata metadata instance
* @return a TikaInputStream instance
* @throws FileNotFoundException if the file does not exist
* or cannot be opened for reading
* @deprecated use {@link #get(Path, Metadata)}. In Tika 2.0,
* this will be removed or modified to throw an IOException.
*/
@Deprecated
public static TikaInputStream get(File file, Metadata metadata)
throws FileNotFoundException {
metadata.set(Metadata.RESOURCE_NAME_KEY, file.getName());
metadata.set(Metadata.CONTENT_LENGTH, Long.toString(file.length()));
return new TikaInputStream(file);
}
/**
* Creates a TikaInputStream from the given database BLOB.
*
* Note that the result set containing the BLOB may need to be kept open
* until the returned TikaInputStream has been processed and closed.
* You must also always explicitly close the returned stream as in
* some cases it may end up writing the blob data to a temporary file.
*
* @param blob database BLOB
* @return a TikaInputStream instance
* @throws SQLException if BLOB data can not be accessed
*/
public static TikaInputStream get(Blob blob) throws SQLException {
return get(blob, new Metadata());
}
/**
* Blob size threshold that limits the largest BLOB size to be
* buffered fully in memory by the {@link #get(Blob, Metadata)}
* method.
*/
private static final int BLOB_SIZE_THRESHOLD = 1024 * 1024;
/**
* Creates a TikaInputStream from the given database BLOB. The BLOB
* length (if available) is stored as input metadata in the given
* metadata instance.
*
* Note that the result set containing the BLOB may need to be kept open
* until the returned TikaInputStream has been processed and closed.
* You must also always explicitly close the returned stream as in
* some cases it may end up writing the blob data to a temporary file.
*
* @param blob database BLOB
* @param metadata metadata instance
* @return a TikaInputStream instance
* @throws SQLException if BLOB data can not be accessed
*/
public static TikaInputStream get(Blob blob, Metadata metadata)
throws SQLException {
long length = -1;
try {
length = blob.length();
metadata.set(Metadata.CONTENT_LENGTH, Long.toString(length));
} catch (SQLException ignore) {
}
// Prefer an in-memory buffer for reasonably sized blobs to reduce
// the likelihood of problems caused by long-lived database accesses
if (0 <= length && length <= BLOB_SIZE_THRESHOLD) {
// the offset in Blob.getBytes() starts at 1
return get(blob.getBytes(1, (int) length), metadata);
} else {
return new TikaInputStream(
new BufferedInputStream(blob.getBinaryStream()),
new TemporaryResources(), length);
}
}
/**
* Creates a TikaInputStream from the resource at the given URI.
*
* Note that you must always explicitly close the returned stream as in
* some cases it may end up writing the resource to a temporary file.
*
* @param uri resource URI
* @return a TikaInputStream instance
* @throws IOException if the resource can not be accessed
*/
public static TikaInputStream get(URI uri) throws IOException {
return get(uri, new Metadata());
}
/**
* Creates a TikaInputStream from the resource at the given URI. The
* available input metadata is stored in the given metadata instance.
*
* Note that you must always explicitly close the returned stream as in
* some cases it may end up writing the resource to a temporary file.
*
* @param uri resource URI
* @param metadata metadata instance
* @return a TikaInputStream instance
* @throws IOException if the resource can not be accessed
*/
public static TikaInputStream get(URI uri, Metadata metadata)
throws IOException {
// Special handling for file:// URIs
if ("file".equalsIgnoreCase(uri.getScheme())) {
Path path = Paths.get(uri);
if (Files.isRegularFile(path)) {
return get(path, metadata);
}
}
return get(uri.toURL(), metadata);
}
/**
* Creates a TikaInputStream from the resource at the given URL.
*
* Note that you must always explicitly close the returned stream as in
* some cases it may end up writing the resource to a temporary file.
*
* @param url resource URL
* @return a TikaInputStream instance
* @throws IOException if the resource can not be accessed
*/
public static TikaInputStream get(URL url) throws IOException {
return get(url, new Metadata());
}
/**
* Creates a TikaInputStream from the resource at the given URL. The
* available input metadata is stored in the given metadata instance.
*
* Note that you must always explicitly close the returned stream as in
* some cases it may end up writing the resource to a temporary file.
*
* @param url resource URL
* @param metadata metadata instance
* @return a TikaInputStream instance
* @throws IOException if the resource can not be accessed
*/
public static TikaInputStream get(URL url, Metadata metadata)
throws IOException {
// Special handling for file:// URLs
if ("file".equalsIgnoreCase(url.getProtocol())) {
try {
Path path = Paths.get(url.toURI());
if (Files.isRegularFile(path)) {
return get(path, metadata);
}
} catch (URISyntaxException e) {
// fall through
}
}
URLConnection connection = url.openConnection();
String path = url.getPath();
int slash = path.lastIndexOf('/');
if (slash + 1 < path.length()) { // works even with -1!
metadata.set(Metadata.RESOURCE_NAME_KEY, path.substring(slash + 1));
}
String type = connection.getContentType();
if (type != null) {
metadata.set(Metadata.CONTENT_TYPE, type);
}
String encoding = connection.getContentEncoding();
if (encoding != null) {
metadata.set(Metadata.CONTENT_ENCODING, encoding);
}
int length = connection.getContentLength();
if (length >= 0) {
metadata.set(Metadata.CONTENT_LENGTH, Integer.toString(length));
}
return new TikaInputStream(
new BufferedInputStream(connection.getInputStream()),
new TemporaryResources(), length);
}
/**
* The path to the file that contains the contents of this stream.
* This is either the original file passed to the
* {@link #TikaInputStream(Path)} constructor or a temporary file created
* by a call to the {@link #getPath()} method. If neither has been called,
* then the value is null.
*/
private Path path;
/**
* Tracker of temporary resources.
*/
private final TemporaryResources tmp;
/**
* Total length of the stream, or -1 if unknown.
*/
private long length;
/**
* Current read position within this stream.
*/
private long position = 0;
/**
* Marked position, or -1 if there is no current mark.
*/
private long mark = -1;
/**
* A opened container, such as a POIFS FileSystem
* for an OLE2 document, or a Zip file for a
* zip based (eg ooxml, odf) document.
*/
private Object openContainer;
/**
* Creates a TikaInputStream instance. This private constructor is used
* by the static factory methods based on the available information.
*
* @param path the path to the file that contains the stream
* @throws IOException if an I/O error occurs
*/
private TikaInputStream(Path path) throws IOException {
super(new BufferedInputStream(Files.newInputStream(path)));
this.path = path;
this.tmp = new TemporaryResources();
this.length = Files.size(path);
}
/**
* Creates a TikaInputStream instance. This private constructor is used
* by the static factory methods based on the available information.
*
* @param file the file that contains the stream
* @throws FileNotFoundException if the file does not exist
* @deprecated use {@link #TikaInputStream(Path)}
*/
@Deprecated
private TikaInputStream(File file) throws FileNotFoundException {
super(new BufferedInputStream(new FileInputStream(file)));
this.path = file.toPath();
this.tmp = new TemporaryResources();
this.length = file.length();
}
/**
* Creates a TikaInputStream instance. This private constructor is used
* by the static factory methods based on the available information.
*
* The given stream needs to be included in the given temporary resource
* collection if the caller wants it also to get closed when the
* {@link #close()} method is invoked.
*
* @param stream buffered stream (must support the mark feature)
* @param tmp tracker for temporary resources associated with this stream
* @param length total length of the stream, or -1 if unknown
*/
private TikaInputStream(
InputStream stream, TemporaryResources tmp, long length) {
super(stream);
this.path = null;
this.tmp = tmp;
this.length = length;
}
/**
* Fills the given buffer with upcoming bytes from this stream without
* advancing the current stream position. The buffer is filled up unless
* the end of stream is encountered before that. This method will block
* if not enough bytes are immediately available.
*
* @param buffer byte buffer
* @return number of bytes written to the buffer
* @throws IOException if the stream can not be read
*/
public int peek(byte[] buffer) throws IOException {
int n = 0;
mark(buffer.length);
int m = read(buffer);
while (m != -1) {
n += m;
if (n < buffer.length) {
m = read(buffer, n, buffer.length - n);
} else {
m = -1;
}
}
reset();
return n;
}
/**
* Returns the open container object, such as a
* POIFS FileSystem in the event of an OLE2
* document being detected and processed by
* the OLE2 detector.
*/
public Object getOpenContainer() {
return openContainer;
}
/**
* Stores the open container object against
* the stream, eg after a Zip contents
* detector has loaded the file to decide
* what it contains.
*/
public void setOpenContainer(Object container) {
openContainer = container;
if (container instanceof Closeable) {
tmp.addResource((Closeable) container);
}
}
public boolean hasFile() {
return path != null;
}
public Path getPath() throws IOException {
if (path == null) {
if (position > 0) {
throw new IOException("Stream is already being read");
} else {
// Spool the entire stream into a temporary file
path = tmp.createTempFile();
Files.copy(in, path, REPLACE_EXISTING);
// Create a new input stream and make sure it'll get closed
InputStream newStream = Files.newInputStream(path);
tmp.addResource(newStream);
// Replace the spooled stream with the new stream in a way
// that still ends up closing the old stream if or when the
// close() method is called. The closing of the new stream
// is already being handled as noted above.
final InputStream oldStream = in;
in = new BufferedInputStream(newStream) {
@Override
public void close() throws IOException {
oldStream.close();
}
};
length = Files.size(path);
}
}
return path;
}
/**
* @see #getPath()
*/
public File getFile() throws IOException {
return getPath().toFile();
}
public FileChannel getFileChannel() throws IOException {
FileChannel channel = FileChannel.open(getPath());
tmp.addResource(channel);
return channel;
}
public boolean hasLength() {
return length != -1;
}
/**
* Returns the length (in bytes) of this stream. Note that if the length
* was not available when this stream was instantiated, then this method
* will use the {@link #getPath()} method to buffer the entire stream to
* a temporary file in order to calculate the stream length. This case
* will only work if the stream has not yet been consumed.
*
* @return stream length
* @throws IOException if the length can not be determined
*/
public long getLength() throws IOException {
if (length == -1) {
getPath(); // updates length internally
}
return length;
}
/**
* Returns the current position within the stream.
*
* @return stream position
*/
public long getPosition() {
return position;
}
@Override
public long skip(long ln) throws IOException {
long n = super.skip(ln);
position += n;
return n;
}
@Override
public void mark(int readlimit) {
super.mark(readlimit);
mark = position;
}
@Override
public boolean markSupported() {
return true;
}
@Override
public void reset() throws IOException {
super.reset();
position = mark;
mark = -1;
}
@Override
public void close() throws IOException {
path = null;
mark = -1;
// The close method was explicitly called, so we indeed
// are expected to close the input stream. Handle that
// by adding that stream as a resource to be tracked before
// closing all of them. This way also possible exceptions from
// the close() calls get managed properly.
tmp.addResource(in);
tmp.close();
}
@Override
protected void afterRead(int n) {
if (n != -1) {
position += n;
}
}
public String toString() {
String str = "TikaInputStream of ";
if (hasFile()) {
str += path.toString();
} else {
str += in.toString();
}
if (openContainer != null) {
str += " (in " + openContainer + ")";
}
return str;
}
}