private static final class ByteSource.ConcatenatedByteSource extends ByteSource
ByteSource.AsCharSource
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 returns 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 while opening the streampublic boolean isEmpty() throws java.io.IOException
ByteSource
ByteSource.sizeIfKnown()
, returning true if it's known to be zero and false if it's known to be non-zero.
If the size is not known, it falls back to opening a stream and checking for EOF.
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 while reading the size of this sourcepublic java.lang.String toString()
toString
in class java.lang.Object