private static final class Files.FileByteSource extends ByteSource
Modifier and Type | Field and Description |
---|---|
private java.io.File |
file |
Modifier | Constructor and Description |
---|---|
private |
FileByteSource(java.io.File file) |
Modifier and Type | Method and Description |
---|---|
java.io.FileInputStream |
openStream()
Opens a new
InputStream for reading from this source. |
byte[] |
read()
Reads the full contents of this byte source as a byte array.
|
long |
size()
Returns the size of this source in bytes, even if doing so requires opening and traversing an
entire stream.
|
Optional<java.lang.Long> |
sizeIfKnown()
Returns the size of this source in bytes, if the size can be easily determined without actually
opening the data stream.
|
java.lang.String |
toString() |
asCharSource, concat, concat, concat, contentEquals, copyTo, copyTo, empty, hash, isEmpty, openBufferedStream, read, slice, wrap
public java.io.FileInputStream openStream() throws java.io.IOException
ByteSource
InputStream
for reading from this source. This method should return a new,
independent stream each time it is called.
The caller is responsible for ensuring that the returned stream is closed.
openStream
in class ByteSource
java.io.IOException
- if an I/O error occurs in the process of opening the streampublic Optional<java.lang.Long> sizeIfKnown()
ByteSource
The default implementation returns Optional.absent()
. Some sources, such as a file,
may return a non-absent value. Note that in such cases, it is possible that this method
will return a different number of bytes than would be returned by reading all of the bytes (for
example, some special files may return a size of 0 despite actually having content when read).
Additionally, for mutable sources such as files, a subsequent read may return a different number of bytes if the contents are changed.
sizeIfKnown
in class ByteSource
public long size() throws java.io.IOException
ByteSource
ByteSource.sizeIfKnown()
.
The default implementation calls ByteSource.sizeIfKnown()
and returns the value if present. If
absent, it will fall back to a heavyweight operation that will open a stream, read (or
skip
, if possible) to the end of the stream and return the total
number of bytes that were read.
Note that for some sources that implement ByteSource.sizeIfKnown()
to provide a more efficient
implementation, it is possible that this method will return a different number of bytes
than would be returned by reading all of the bytes (for example, some special files may return
a size of 0 despite actually having content when read).
In either case, for mutable sources such as files, a subsequent read may return a different number of bytes if the contents are changed.
size
in class ByteSource
java.io.IOException
- if an I/O error occurs in the process of reading the size of this sourcepublic byte[] read() throws java.io.IOException
ByteSource
read
in class ByteSource
java.io.IOException
- if an I/O error occurs in the process of reading from this sourcepublic java.lang.String toString()
toString
in class java.lang.Object