java.lang.Object | |
↳ | com.atlassian.jira.util.IOUtil |
General IO Stream manipulation.
This class provides static utility methods for input/output operations, particularly buffered
copying between sources (InputStream
, Reader
, String
and
byte[]
) and destinations (OutputStream
, Writer
,
String
and byte[]
).
Unless otherwise noted, these copy
methods do not flush or close the
streams. Often, doing so would require making non-portable assumptions about the streams' origin
and further use. This means that both streams' close()
methods must be called after
copying. if one omits this step, then the stream resources (sockets, file descriptors) are
released when the associated Stream is garbage-collected. It is not a good idea to rely on this
mechanism. For a good overview of the distinction between "memory management" and "resource
management", see this
UnixReview article
For each copy
method, a variant is provided that allows the caller to specify the
buffer size (the default is 4k). As the buffer size can have a fairly large impact on speed, this
may be worth tweaking. Often "large buffer -> faster" does not hold, even for large data
transfers.
For byte-to-char methods, a copy
variant allows the encoding to be selected
(otherwise the platform default is used).
The copy
methods use an internal buffer when copying. It is therefore advisable
not to deliberately wrap the stream arguments to the copy
methods in
Buffered*
streams. For example, don't do the
following:
copy( new BufferedInputStream( in ), new BufferedOutputStream( out ) );
The rationale is as follows:
Imagine that an InputStream's read() is a very expensive operation, which would usually suggest
wrapping in a BufferedInputStream. The BufferedInputStream works by issuing infrequent
read(byte[], int, int)
requests on the underlying InputStream, to
fill an internal buffer, from which further read
requests can inexpensively get
their data (until the buffer runs out).
However, the copy
methods do the same thing, keeping an internal buffer,
populated by read(byte[], int, int)
requests. Having two buffers
(or three if the destination stream is also buffered) is pointless, and the unnecessary buffer
management hurts performance slightly (about 3%, according to some simple experiments).
Public Methods | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
This method is deprecated.
Buffering streams is actively harmful! See the class description as to why. Use
copy(InputStream, OutputStream) instead.
| |||||||||||
Compare the contents of two Streams to determine if they are equal or not.
| |||||||||||
Copy bytes from an
InputStream to an OutputStream . | |||||||||||
Copy and convert bytes from a
byte[] to chars on a
Writer . | |||||||||||
Serialize chars from a
Reader to bytes on an OutputStream , and
flush the OutputStream . | |||||||||||
Copy and convert bytes from an
InputStream to chars on a
Writer , using the specified encoding. | |||||||||||
Copy and convert bytes from an
InputStream to chars on a
Writer , using the specified encoding. | |||||||||||
Copy and convert bytes from an
InputStream to chars on a
Writer . | |||||||||||
Copy chars from a
String to a Writer . | |||||||||||
Copy the contents from one file to another.
| |||||||||||
Copy chars from a
Reader to a Writer . | |||||||||||
Copy and convert bytes from a
byte[] to chars on a
Writer , using the specified encoding. | |||||||||||
Copy bytes from a
byte[] to an OutputStream . | |||||||||||
Serialize chars from a
String to bytes on an OutputStream , and
flush the OutputStream . | |||||||||||
Copy and convert bytes from a
byte[] to chars on a
Writer , using the specified encoding. | |||||||||||
Serialize chars from a
String to bytes on an OutputStream , and
flush the OutputStream . | |||||||||||
Copy chars from a
Reader to a Writer . | |||||||||||
Copy and convert bytes from an
InputStream to chars on a
Writer . | |||||||||||
Serialize chars from a
Reader to bytes on an OutputStream , and
flush the OutputStream . | |||||||||||
Copy bytes from an
InputStream to an OutputStream . | |||||||||||
Copy bytes from a
byte[] to an OutputStream . | |||||||||||
Copy and convert bytes from a
byte[] to chars on a
Writer . | |||||||||||
Reads at most the given number of bytes from the input stream and returns them in an array.
| |||||||||||
Unconditionally close an
Reader . | |||||||||||
Unconditionally close an
OutputStream . | |||||||||||
Unconditionally close an
InputStream . | |||||||||||
Unconditionally close an
Writer . | |||||||||||
Get the contents of a
Reader as a byte[] . | |||||||||||
Get the contents of a
Reader as a byte[] . | |||||||||||
Get the contents of an
InputStream as a byte[] . | |||||||||||
Get the contents of a
String as a byte[] . | |||||||||||
Get the contents of an
InputStream as a byte[] . | |||||||||||
Get the contents of a
String as a byte[] . | |||||||||||
Get the contents of a
byte[] as a String. | |||||||||||
Get the contents of a
Reader as a String. | |||||||||||
Get the contents of a
byte[] as a String. | |||||||||||
Get the contents of an
InputStream as a String. | |||||||||||
Get the contents of an
InputStream as a String. | |||||||||||
Get the contents of an
InputStream as a String. | |||||||||||
Get the contents of a
Reader as a String. | |||||||||||
Get the contents of a
byte[] as a String. | |||||||||||
Get the contents of an
InputStream as a String. | |||||||||||
Get the contents of a
byte[] as a String. |
[Expand]
Inherited Methods | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
From class
java.lang.Object
|
This method is deprecated.
Buffering streams is actively harmful! See the class description as to why. Use
copy(InputStream, OutputStream)
instead.
Copy bytes from an InputStream
to an
OutputStream
, with buffering.
This is equivalent to passing a
java.io.BufferedInputStream and
java.io.BufferedOutputStream to copy(InputStream, OutputStream)
,
and flushing the output stream afterwards. The streams are not closed
after the copy.
IOException |
---|
Compare the contents of two Streams to determine if they are equal or not.
input1 | the first stream |
---|---|
input2 | the second stream |
IOException |
---|
Copy bytes from an InputStream
to an OutputStream
.
bufferSize | Size of internal buffer to use. |
---|
IOException |
---|
Copy and convert bytes from a byte[]
to chars on a
Writer
.
The platform's default encoding is used for the byte-to-char conversion.
IOException |
---|
Serialize chars from a Reader
to bytes on an OutputStream
, and
flush the OutputStream
.
IOException |
---|
Copy and convert bytes from an InputStream
to chars on a
Writer
, using the specified encoding.
encoding | The name of a supported character encoding. See the IANA Charset Registry for a list of valid encoding types. |
---|
IOException |
---|
Copy and convert bytes from an InputStream
to chars on a
Writer
, using the specified encoding.
encoding | The name of a supported character encoding. See the IANA Charset Registry for a list of valid encoding types. |
---|---|
bufferSize | Size of internal buffer to use. |
IOException |
---|
Copy and convert bytes from an InputStream
to chars on a
Writer
.
The platform's default encoding is used for the byte-to-char conversion.
IOException |
---|
Copy chars from a String
to a Writer
.
IOException |
---|
Copy the contents from one file to another.
src | the file to be copied |
---|---|
dst | the file to be copied to |
IOException | if there are any problems in the copy operation |
---|
Copy chars from a Reader
to a Writer
.
IOException |
---|
Copy and convert bytes from a byte[]
to chars on a
Writer
, using the specified encoding.
encoding | The name of a supported character encoding. See the IANA Charset Registry for a list of valid encoding types. |
---|---|
bufferSize | Size of internal buffer to use. |
IOException |
---|
Copy bytes from a byte[]
to an OutputStream
.
bufferSize | Size of internal buffer to use. |
---|
IOException |
---|
Serialize chars from a String
to bytes on an OutputStream
, and
flush the OutputStream
.
IOException |
---|
Copy and convert bytes from a byte[]
to chars on a
Writer
, using the specified encoding.
encoding | The name of a supported character encoding. See the IANA Charset Registry for a list of valid encoding types. |
---|
IOException |
---|
Serialize chars from a String
to bytes on an OutputStream
, and
flush the OutputStream
.
bufferSize | Size of internal buffer to use. |
---|
IOException |
---|
Copy chars from a Reader
to a Writer
.
bufferSize | Size of internal buffer to use. |
---|
IOException |
---|
Copy and convert bytes from an InputStream
to chars on a
Writer
.
The platform's default encoding is used for the byte-to-char conversion.
bufferSize | Size of internal buffer to use. |
---|
IOException |
---|
Serialize chars from a Reader
to bytes on an OutputStream
, and
flush the OutputStream
.
bufferSize | Size of internal buffer to use. |
---|
IOException |
---|
Copy bytes from an InputStream
to an OutputStream
.
IOException |
---|
Copy bytes from a byte[]
to an OutputStream
.
IOException |
---|
Copy and convert bytes from a byte[]
to chars on a
Writer
.
The platform's default encoding is used for the byte-to-char conversion.
bufferSize | Size of internal buffer to use. |
---|
IOException |
---|
Reads at most the given number of bytes from the input stream and returns them in an array. Does not
close the InputStream
.
is | the InputStream to read bytes from. |
---|---|
numBytes | the maximum number of bytes to return. |
IOException | if the stream cannot be read. |
---|
Unconditionally close an Reader
.
Equivalent to close()
, except any exceptions will be ignored.
input | A (possibly null) Reader |
---|
Unconditionally close an OutputStream
.
Equivalent to close()
, except any exceptions will be ignored.
output | A (possibly null) OutputStream |
---|
Unconditionally close an InputStream
.
Equivalent to close()
, except any exceptions will be ignored.
input | A (possibly null) InputStream |
---|
Unconditionally close an Writer
.
Equivalent to close()
, except any exceptions will be ignored.
output | A (possibly null) Writer |
---|
Get the contents of a Reader
as a byte[]
.
bufferSize | Size of internal buffer to use. |
---|
IOException |
---|
Get the contents of a Reader
as a byte[]
.
IOException |
---|
Get the contents of an InputStream
as a byte[]
.
IOException |
---|
Get the contents of a String
as a byte[]
.
bufferSize | Size of internal buffer to use. |
---|
IOException |
---|
Get the contents of an InputStream
as a byte[]
.
bufferSize | Size of internal buffer to use. |
---|
IOException |
---|
Get the contents of a String
as a byte[]
.
IOException |
---|
Get the contents of a byte[]
as a String.
encoding | The name of a supported character encoding. See the IANA Charset Registry for a list of valid encoding types. |
---|---|
bufferSize | Size of internal buffer to use. |
IOException |
---|
Get the contents of a Reader
as a String.
bufferSize | Size of internal buffer to use. |
---|
IOException |
---|
Get the contents of a byte[]
as a String.
The platform's default encoding is used for the byte-to-char conversion.
IOException |
---|
Get the contents of an InputStream
as a String.
The platform's default encoding is used for the byte-to-char conversion.
bufferSize | Size of internal buffer to use. |
---|
IOException |
---|
Get the contents of an InputStream
as a String.
encoding | The name of a supported character encoding. See the IANA Charset Registry for a list of valid encoding types. |
---|---|
bufferSize | Size of internal buffer to use. |
IOException |
---|
Get the contents of an InputStream
as a String.
The platform's default encoding is used for the byte-to-char conversion.
IOException |
---|
Get the contents of a Reader
as a String.
IOException |
---|
Get the contents of a byte[]
as a String.
encoding | The name of a supported character encoding. See the IANA Charset Registry for a list of valid encoding types. |
---|
IOException |
---|
Get the contents of an InputStream
as a String.
encoding | The name of a supported character encoding. See the IANA Charset Registry for a list of valid encoding types. |
---|
IOException |
---|
Get the contents of a byte[]
as a String.
The platform's default encoding is used for the byte-to-char conversion.
bufferSize | Size of internal buffer to use. |
---|
IOException |
---|