org.apache.tika.io

Class TikaInputStream

java.lang.Object

java.io.InputStream

java.io.FilterInputStream

org.apache.tika.io.ProxyInputStream

org.apache.tika.io.TaggedInputStream

org.apache.tika.io.TikaInputStream

All Implemented Interfaces:

Closeable, AutoCloseable

public class TikaInputStream
extends TaggedInputStream

Input stream with extended capabilities. The purpose of this class is to allow files and other resources and information to be associated with the InputStream instance passed through the 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 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 InputStream. A TikaInputStream instance is also guaranteed to support the mark(int) feature.

Code that wants to access the underlying file or other resources associated with a TikaInputStream should first use the get(InputStream) factory method to cast or wrap a given InputStream into a TikaInputStream instance.

Since:

Apache Tika 0.8

Field Summary

Fields inherited from class java.io.FilterInputStream

in

Method Summary

Methods

Modifier and Type	Method and Description
protected void	afterRead(int n) Invoked by the read methods after the proxied call has returned successfully.
static TikaInputStream	cast(InputStream stream) Returns the given stream casts to a TikaInputStream, or null if the stream is not a TikaInputStream.
void	close() Invokes the delegate's close() method.
static TikaInputStream	get(Blob blob) Creates a TikaInputStream from the given database BLOB.
static TikaInputStream	get(Blob blob, Metadata metadata) Creates a TikaInputStream from the given database BLOB.
static TikaInputStream	get(byte[] data) Creates a TikaInputStream from the given array of bytes.
static TikaInputStream	get(byte[] data, Metadata metadata) Creates a TikaInputStream from the given array of bytes.
static TikaInputStream	get(File file) Creates a TikaInputStream from the given file.
static TikaInputStream	get(File file, Metadata metadata) Creates a TikaInputStream from the given file.
static TikaInputStream	get(InputStream stream) Casts or wraps the given stream to a TikaInputStream instance.
static TikaInputStream	get(InputStream stream, TemporaryResources tmp) Casts or wraps the given stream to a TikaInputStream instance.
static TikaInputStream	get(URI uri) Creates a TikaInputStream from the resource at the given URI.
static TikaInputStream	get(URI uri, Metadata metadata) Creates a TikaInputStream from the resource at the given URI.
static TikaInputStream	get(URL url) Creates a TikaInputStream from the resource at the given URL.
static TikaInputStream	get(URL url, Metadata metadata) Creates a TikaInputStream from the resource at the given URL.
File	getFile()
FileChannel	getFileChannel()
long	getLength() Returns the length (in bytes) of this stream.
Object	getOpenContainer() 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.
long	getPosition() Returns the current position within the stream.
boolean	hasFile()
boolean	hasLength()
static boolean	isTikaInputStream(InputStream stream) Checks whether the given stream is a TikaInputStream instance.
void	mark(int readlimit) Invokes the delegate's mark(int) method.
boolean	markSupported() Invokes the delegate's markSupported() method.
int	peek(byte[] buffer) Fills the given buffer with upcoming bytes from this stream without advancing the current stream position.
void	reset() Invokes the delegate's reset() method.
void	setOpenContainer(Object container) Stores the open container object against the stream, eg after a Zip contents detector has loaded the file to decide what it contains.
long	skip(long ln) Invokes the delegate's skip(long) method.
String	toString()

Methods inherited from class org.apache.tika.io.TaggedInputStream

handleIOException, isCauseOf, throwIfCauseOf

Methods inherited from class org.apache.tika.io.ProxyInputStream

available, beforeRead, read, read, read

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Method Detail

isTikaInputStream

public static boolean isTikaInputStream(InputStream stream)

Checks whether the given stream is a TikaInputStream instance. The given stream can be null, in which case the return value is false.

Parameters:

stream - input stream, possibly null

Returns:

true if the stream is a TikaInputStream instance, false otherwise

get

public static TikaInputStream get(InputStream stream,
                  TemporaryResources tmp)

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 get(InputStream) alternative when you don't explicitly close the returned stream. The recommended access pattern is:

 TemporaryResources tmp = new TemporaryResources();
 try {
     TikaInputStream stream = TikaInputStream.get(..., tmp);
     // process stream but don't close it
 } finally {
     tmp.close();
 }
 

The given stream instance will not be closed when the TemporaryResources.close() method is called. The caller is expected to explicitly close the original stream when it's no longer used.

Parameters:

stream - normal input stream

Returns:

a TikaInputStream instance

Since:

Apache Tika 0.10

get

public static TikaInputStream get(InputStream stream)

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 get(InputStream, TemporaryResources) alternative when you do explicitly close the returned stream. The recommended access pattern is:

 TikaInputStream stream = TikaInputStream.get(...);
 try {
     // process stream
 } finally {
     stream.close();
 }
 

The given stream instance will be closed along with any other resources associated with the returned TikaInputStream instance when the close() method is called.

Parameters:

stream - normal input stream

Returns:

a TikaInputStream instance

cast

public static TikaInputStream cast(InputStream stream)

Returns the given stream casts to a TikaInputStream, or null if the stream is not a TikaInputStream.

Parameters:

stream - normal input stream

Returns:

a TikaInputStream instance

Since:

Apache Tika 0.10

get

public static TikaInputStream get(byte[] data)

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.

Parameters:

data - input data

Returns:

a TikaInputStream instance

get

public static TikaInputStream get(byte[] data,
                  Metadata 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.

Parameters:

data - input data

metadata - metadata instance

Returns:

a TikaInputStream instance

Throws:

IOException

get

public static TikaInputStream get(File file)
                           throws FileNotFoundException

Creates a TikaInputStream from the given file.

Note that you must always explicitly close the returned stream to prevent leaking open file handles.

Parameters:

file - input file

Returns:

a TikaInputStream instance

Throws:

FileNotFoundException - if the file does not exist

get

public static TikaInputStream get(File file,
                  Metadata metadata)
                           throws FileNotFoundException

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.

Parameters:

file - input file

metadata - metadata instance

Returns:

a TikaInputStream instance

Throws:

FileNotFoundException - if the file does not exist

get

public static TikaInputStream get(Blob blob)
                           throws SQLException

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.

Parameters:

blob - database BLOB

Returns:

a TikaInputStream instance

Throws:

SQLException - if BLOB data can not be accessed

get

public static TikaInputStream get(Blob blob,
                  Metadata metadata)
                           throws SQLException

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.

Parameters:

blob - database BLOB

metadata - metadata instance

Returns:

a TikaInputStream instance

Throws:

SQLException - if BLOB data can not be accessed

get

public static TikaInputStream get(URI uri)
                           throws IOException

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.

Parameters:

uri - resource URI

Returns:

a TikaInputStream instance

Throws:

IOException - if the resource can not be accessed

get

public static TikaInputStream get(URI uri,
                  Metadata metadata)
                           throws IOException

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.

Parameters:

uri - resource URI

metadata - metadata instance

Returns:

a TikaInputStream instance

Throws:

IOException - if the resource can not be accessed

get

public static TikaInputStream get(URL url)
                           throws IOException

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.

Parameters:

url - resource URL

Returns:

a TikaInputStream instance

Throws:

IOException - if the resource can not be accessed

get

public static TikaInputStream get(URL url,
                  Metadata metadata)
                           throws IOException

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.

Parameters:

url - resource URL

metadata - metadata instance

Returns:

a TikaInputStream instance

Throws:

IOException - if the resource can not be accessed

peek

public int peek(byte[] buffer)
         throws IOException

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.

Parameters:

buffer - byte buffer

Returns:

number of bytes written to the buffer

Throws:

IOException - if the stream can not be read

getOpenContainer

public Object getOpenContainer()

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.

setOpenContainer

public void setOpenContainer(Object container)

Stores the open container object against the stream, eg after a Zip contents detector has loaded the file to decide what it contains.

hasFile

public boolean hasFile()

getFile

public File getFile()
             throws IOException

Throws:

IOException

getFileChannel

public FileChannel getFileChannel()
                           throws IOException

Throws:

IOException

hasLength

public boolean hasLength()

getLength

public long getLength()
               throws IOException

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 getFile() 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.

Returns:

stream length

Throws:

IOException - if the length can not be determined

getPosition

public long getPosition()

Returns the current position within the stream.

Returns:

stream position

skip

public long skip(long ln)
          throws IOException

Description copied from class: ProxyInputStream

Invokes the delegate's skip(long) method.

Overrides:

skip in class ProxyInputStream

Parameters:

ln - the number of bytes to skip

Returns:

the actual number of bytes skipped

Throws:

IOException - if an I/O error occurs

mark

public void mark(int readlimit)

Description copied from class: ProxyInputStream

Invokes the delegate's mark(int) method.

Overrides:

mark in class ProxyInputStream

Parameters:

readlimit - read ahead limit

markSupported

public boolean markSupported()

Description copied from class: ProxyInputStream

Invokes the delegate's markSupported() method.

Overrides:

markSupported in class ProxyInputStream

Returns:

true if mark is supported, otherwise false

reset

public void reset()
           throws IOException

Description copied from class: ProxyInputStream

Invokes the delegate's reset() method.

Overrides:

reset in class ProxyInputStream

Throws:

IOException - if an I/O error occurs

close

public void close()
           throws IOException

Description copied from class: ProxyInputStream

Invokes the delegate's close() method.

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Overrides:

close in class ProxyInputStream

Throws:

IOException - if an I/O error occurs

afterRead

protected void afterRead(int n)

Description copied from class: ProxyInputStream

Invoked by the read methods after the proxied call has returned successfully. The number of bytes returned to the caller (or -1 if the end of stream was reached) is given as an argument.

Subclasses can override this method to add common post-processing functionality without having to override all the read methods. The default implementation does nothing.

Note this method is not called from ProxyInputStream.skip(long) or ProxyInputStream.reset(). You need to explicitly override those methods if you want to add post-processing steps also to them.

Overrides:

afterRead in class ProxyInputStream

Parameters:

n - number of bytes read, or -1 if the end of stream was reached

toString

public String toString()

Overrides:

toString in class TaggedInputStream