public class ObservableInputStream extends ProxyInputStream
ObservableInputStream
allows, that an InputStream may be consumed by other receivers, apart from the
thread, which is reading it. The other consumers are implemented as instances of ObservableInputStream.Observer
.
A typical application may be the generation of a MessageDigest
on the fly.
Note: The ObservableInputStream
is not thread safe, as instances of InputStream usually
aren't. If you must access the stream from multiple threads, then synchronization, locking, or a similar means must
be used.
MessageDigestCalculatingInputStream
Modifier and Type | Class and Description |
---|---|
static class |
ObservableInputStream.Observer
Abstracts observer callback for
ObservableInputStream s. |
in
Constructor and Description |
---|
ObservableInputStream(InputStream inputStream)
Creates a new ObservableInputStream for the given InputStream.
|
ObservableInputStream(InputStream inputStream,
ObservableInputStream.Observer... observers)
Creates a new ObservableInputStream for the given InputStream.
|
Modifier and Type | Method and Description |
---|---|
void |
add(ObservableInputStream.Observer observer)
Adds an Observer.
|
void |
close()
Invokes the delegate's
close() method. |
void |
consume()
Reads all data from the underlying
InputStream , while notifying the observers. |
List<ObservableInputStream.Observer> |
getObservers()
Gets all currently registered observers.
|
protected void |
noteClosed()
Notifies the observers by invoking
ObservableInputStream.Observer.finished() . |
protected void |
noteDataByte(int value)
Notifies the observers by invoking
ObservableInputStream.Observer.data(int) with the given arguments. |
protected void |
noteDataBytes(byte[] buffer,
int offset,
int length)
Notifies the observers by invoking
ObservableInputStream.Observer.data(byte[],int,int) with the given arguments. |
protected void |
noteError(IOException exception)
Notifies the observers by invoking
ObservableInputStream.Observer.error(IOException) with the given argument. |
protected void |
noteFinished()
Notifies the observers by invoking
ObservableInputStream.Observer.finished() . |
int |
read()
Invokes the delegate's
read() method. |
int |
read(byte[] buffer)
Invokes the delegate's
read(byte[]) method. |
int |
read(byte[] buffer,
int offset,
int length)
Invokes the delegate's
read(byte[], int, int) method. |
void |
remove(ObservableInputStream.Observer observer)
Removes an Observer.
|
void |
removeAllObservers()
Removes all Observers.
|
afterRead, available, beforeRead, handleIOException, mark, markSupported, reset, skip
public ObservableInputStream(InputStream inputStream)
inputStream
- the input stream to observe.public ObservableInputStream(InputStream inputStream, ObservableInputStream.Observer... observers)
inputStream
- the input stream to observe.observers
- List of observer callbacks.public void add(ObservableInputStream.Observer observer)
observer
- the observer to add.public void close() throws IOException
ProxyInputStream
close()
method.close
in interface Closeable
close
in interface AutoCloseable
close
in class ProxyInputStream
IOException
- if an I/O error occurs.public void consume() throws IOException
InputStream
, while notifying the observers.IOException
- The underlying InputStream
, or either of the observers has thrown an exception.public List<ObservableInputStream.Observer> getObservers()
protected void noteClosed() throws IOException
ObservableInputStream.Observer.finished()
.IOException
- Some observer has thrown an exception, which is being passed down.protected void noteDataByte(int value) throws IOException
ObservableInputStream.Observer.data(int)
with the given arguments.value
- Passed to the observers.IOException
- Some observer has thrown an exception, which is being passed down.protected void noteDataBytes(byte[] buffer, int offset, int length) throws IOException
ObservableInputStream.Observer.data(byte[],int,int)
with the given arguments.buffer
- Passed to the observers.offset
- Passed to the observers.length
- Passed to the observers.IOException
- Some observer has thrown an exception, which is being passed down.protected void noteError(IOException exception) throws IOException
ObservableInputStream.Observer.error(IOException)
with the given argument.exception
- Passed to the observers.IOException
- Some observer has thrown an exception, which is being passed down. This may be the same
exception, which has been passed as an argument.protected void noteFinished() throws IOException
ObservableInputStream.Observer.finished()
.IOException
- Some observer has thrown an exception, which is being passed down.public int read() throws IOException
ProxyInputStream
read()
method.read
in class ProxyInputStream
IOException
- if an I/O error occurs.public int read(byte[] buffer) throws IOException
ProxyInputStream
read(byte[])
method.read
in class ProxyInputStream
buffer
- the buffer to read the bytes intoIOException
- if an I/O error occurs.public int read(byte[] buffer, int offset, int length) throws IOException
ProxyInputStream
read(byte[], int, int)
method.read
in class ProxyInputStream
buffer
- the buffer to read the bytes intooffset
- The start offsetlength
- The number of bytes to readIOException
- if an I/O error occurs.public void remove(ObservableInputStream.Observer observer)
observer
- the observer to removepublic void removeAllObservers()
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