java.lang.Object | ||
↳ | java.io.InputStream | |
↳ | java.io.FileInputStream |
Known Direct Subclasses |
Known Indirect Subclasses |
A specialized InputStream
that reads from a file in the file system.
All read requests made by calling methods in this class are directly
forwarded to the equivalent function of the underlying operating system.
Since this may induce some performance penalty, in particular if many small
read requests are made, a FileInputStream is often wrapped by a
BufferedInputStream.
Public Constructors | |||||||||||
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Constructs a new
FileInputStream based on file . | |||||||||||
Constructs a new
FileInputStream on the file named
fileName . |
Public Methods | |||||||||||
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Returns the number of bytes that are available before this stream will
block.
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Closes this stream.
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Returns the
FileChannel equivalent to this input stream. | |||||||||||
Returns the
FileDescriptor representing the operating system
resource for this stream. | |||||||||||
Reads at most
count bytes from this stream and stores them in the
byte array buffer starting at offset . | |||||||||||
Reads bytes from this stream and stores them in the byte array
buffer . | |||||||||||
Reads a single byte from this stream and returns it as an integer in the
range from 0 to 255.
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Skips
count number of bytes in this stream. |
Protected Methods | |||||||||||
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Ensures that all resources for this stream are released when it is about
to be garbage collected.
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[Expand]
Inherited Methods | |||||||||||
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From class java.io.InputStream
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From class java.lang.Object
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From interface java.io.Closeable
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Constructs a new FileInputStream
based on file
.
file | the file from which this stream reads. |
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FileNotFoundException | if file does not exist. |
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SecurityException | if a SecurityManager is installed and it denies the
read request.
|
Constructs a new FileInputStream
on the FileDescriptor
fd
. The file must already be open, therefore no
FileNotFoundException
will be thrown.
fd | the FileDescriptor from which this stream reads. |
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NullPointerException | if fd is null . |
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SecurityException | if a SecurityManager is installed and it denies the
read request.
|
Constructs a new FileInputStream
on the file named
fileName
. The path of fileName
may be absolute or
relative to the system property "user.dir"
.
fileName | the path and name of the file from which this stream reads. |
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FileNotFoundException | if there is no file named fileName . |
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SecurityException | if a SecurityManager is installed and it denies the
read request.
|
Returns the number of bytes that are available before this stream will block. This method always returns the size of the file minus the current position.
IOException | if an error occurs in this stream. |
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Closes this stream.
IOException | if an error occurs attempting to close this stream. |
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Returns the FileChannel
equivalent to this input stream.
The file channel is read-only and has an initial position within the file that is the same as the current position of this stream within the file. All changes made to the underlying file descriptor state via the channel are visible by the input stream and vice versa.
Returns the FileDescriptor
representing the operating system
resource for this stream.
FileDescriptor
for this stream.IOException | if an error occurs while getting this stream's
FileDescriptor .
|
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Reads at most count
bytes from this stream and stores them in the
byte array buffer
starting at offset
.
buffer | the byte array in which to store the bytes read. |
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offset | the initial position in buffer to store the bytes read
from this stream. |
count | the maximum number of bytes to store in buffer . |
IndexOutOfBoundsException | if offset < 0 or count < 0 , or if
offset + count is greater than the size of
buffer . |
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IOException | if the stream is closed or another IOException occurs. |
Reads bytes from this stream and stores them in the byte array
buffer
.
buffer | the byte array in which to store the bytes read. |
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IOException | if this stream is closed or another I/O error occurs. |
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Reads a single byte from this stream and returns it as an integer in the range from 0 to 255. Returns -1 if the end of this stream has been reached.
IOException | if this stream is closed or another I/O error occurs. |
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Skips count
number of bytes in this stream. Subsequent
read()
's will not return these bytes unless reset()
is
used. This method may perform multiple reads to read count
bytes.
count | the number of bytes to skip. |
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IOException | if count < 0 , this stream is closed or another
IOException occurs.
|
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Ensures that all resources for this stream are released when it is about to be garbage collected.
IOException | if an error occurs attempting to finalize this stream. |
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