Klasse DelegatingInputStream
- Alle implementierten Schnittstellen:
Closeable,AutoCloseable
- Bekannte direkte Unterklassen:
XORInputStream
DelegatingInputStream contains some other input stream, which it uses as its basic source of data,
possibly transforming the data along the way or providing additional functionality. The class
DelegatingInputStream itself simply overrides all (see note below) methods of InputStream
with versions that pass all requests to the contained input stream. Subclasses of DelegatingInputStream
may further override some of these methods and may also provide additional methods and fields.
Note: The only difference to FilterInputStream is that DelegatingInputStream does
not override InputStream.read(byte[]) or InputStream.read(byte[], int, int) but rather exposes the original
implementations of InputStream which call read() instead of their delegate counterparts.
- Autor:
- Eike Stepper
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Feldübersicht
Felder -
Konstruktorübersicht
KonstruktorenModifiziererKonstruktorBeschreibungprotectedCreates aDelegatingInputStreamby assigning the argumentinto the fieldthis.inso as to remember it for later use. -
Methodenübersicht
Modifizierer und TypMethodeBeschreibungintReturns the number of bytes that can be read from this input stream without blocking.voidclose()Closes this input stream and releases any system resources associated with the stream.voidmark(int readlimit) Marks the current position in this input stream.booleanTests if this input stream supports themarkandresetmethods.intread()Reads the next byte of data from this input stream.voidreset()Repositions this stream to the position at the time themarkmethod was last called on this input stream.longskip(long n) Skips over and discardsnbytes of data from the input stream.Von Klasse geerbte Methoden java.io.InputStream
nullInputStream, read, read, readAllBytes, readNBytes, readNBytes, skipNBytes, transferTo
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Felddetails
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in
The input stream to be filtered.
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Konstruktordetails
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DelegatingInputStream
Creates aDelegatingInputStreamby assigning the argumentinto the fieldthis.inso as to remember it for later use.- Parameter:
in- the underlying input stream, ornullif this instance is to be created without an underlying stream.
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Methodendetails
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getDelegate
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read
Reads the next byte of data from this input stream. The value byte is returned as anintin the range0to255. If no byte is available because the end of the stream has been reached, the value-1is returned. This method blocks until input data is available, the end of the stream is detected, or an exception is thrown.This method simply performs
in.read()and returns the result.- Angegeben von:
readin KlasseInputStream- Gibt zurück:
- the next byte of data, or
-1if the end of the stream is reached. - Löst aus:
IOException- if an I/O error occurs.- Siehe auch:
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skip
Skips over and discardsnbytes of data from the input stream. Theskipmethod may, for a variety of reasons, end up skipping over some smaller number of bytes, possibly0. The actual number of bytes skipped is returned.This method simply performs
in.skip(n).- Setzt außer Kraft:
skipin KlasseInputStream- Parameter:
n- the number of bytes to be skipped.- Gibt zurück:
- the actual number of bytes skipped.
- Löst aus:
IOException- if an I/O error occurs.
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available
Returns the number of bytes that can be read from this input stream without blocking.This method simply performs
in.available()and returns the result.- Setzt außer Kraft:
availablein KlasseInputStream- Gibt zurück:
- the number of bytes that can be read from the input stream without blocking.
- Löst aus:
IOException- if an I/O error occurs.- Siehe auch:
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close
Closes this input stream and releases any system resources associated with the stream. This method simply performsin.close().- Angegeben von:
closein SchnittstelleAutoCloseable- Angegeben von:
closein SchnittstelleCloseable- Setzt außer Kraft:
closein KlasseInputStream- Löst aus:
IOException- if an I/O error occurs.- Siehe auch:
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mark
public void mark(int readlimit) Marks the current position in this input stream. A subsequent call to theresetmethod repositions this stream at the last marked position so that subsequent reads re-read the same bytes.The
readlimitargument tells this input stream to allow that many bytes to be read before the mark position gets invalidated.This method simply performs
in.mark(readlimit).- Setzt außer Kraft:
markin KlasseInputStream- Parameter:
readlimit- the maximum limit of bytes that can be read before the mark position becomes invalid.- Siehe auch:
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reset
Repositions this stream to the position at the time themarkmethod was last called on this input stream.This method simply performs
in.reset().Stream marks are intended to be used in situations where you need to read ahead a little to see what's in the stream. Often this is most easily done by invoking some general parser. If the stream is of the type handled by the parse, it just chugs along happily. If the stream is not of that type, the parser should toss an exception when it fails. If this happens within readlimit bytes, it allows the outer code to reset the stream and try another parser.
- Setzt außer Kraft:
resetin KlasseInputStream- Löst aus:
IOException- if the stream has not been marked or if the mark has been invalidated.- Siehe auch:
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markSupported
public boolean markSupported()Tests if this input stream supports themarkandresetmethods. This method simply performsin.markSupported().- Setzt außer Kraft:
markSupportedin KlasseInputStream- Gibt zurück:
trueif this stream type supports themarkandresetmethod;falseotherwise.- Siehe auch:
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