private static final class ByteSource.ConcatenatedByteSource extends ByteSource
Modifier and Type | Field and Description |
---|---|
(package private) java.lang.Iterable<? extends ByteSource> |
sources |
Constructor and Description |
---|
ConcatenatedByteSource(java.lang.Iterable<? extends ByteSource> sources) |
Modifier and Type | Method and Description |
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boolean |
isEmpty()
Returns whether the source has zero bytes.
|
java.io.InputStream |
openStream()
Opens a new
InputStream for reading from this source. |
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, openBufferedStream, read, read, slice, wrap
final java.lang.Iterable<? extends ByteSource> sources
ConcatenatedByteSource(java.lang.Iterable<? extends ByteSource> sources)
public java.io.InputStream 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 boolean isEmpty() throws java.io.IOException
ByteSource
ByteSource.sizeIfKnown()
returns zero, falling back to opening a stream and checking for EOF if the
size is not known.
Note that, in cases where sizeIfKnown
returns zero, it is possible that bytes
are actually available for reading. (For example, some special files may return a size of 0
despite actually having content when read.) This means that a source may return true
from isEmpty()
despite having readable content.
isEmpty
in class ByteSource
java.io.IOException
- if an I/O error occurspublic 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 java.lang.String toString()
toString
in class java.lang.Object