public class PGCopyInputStream extends InputStream implements CopyOut
| Constructor and Description |
|---|
PGCopyInputStream(CopyOut op)
Use given CopyOut operation for reading
|
PGCopyInputStream(PGConnection connection,
String sql)
Uses given connection for specified COPY TO STDOUT operation
|
| Modifier and Type | Method and Description |
|---|---|
int |
available()
Returns an estimate of the number of bytes that can be read (or
skipped over) from this input stream without blocking by the next
invocation of a method for this input stream.
|
void |
cancelCopy()
Cancels this copy operation, discarding any exchanged data.
|
void |
close()
Closes this input stream and releases any system resources associated
with the stream.
|
int |
getFieldCount() |
int |
getFieldFormat(int field) |
int |
getFormat() |
long |
getHandledRowCount()
After succesful end of copy, returns the number of database records handled in that operation.
|
boolean |
isActive() |
int |
read()
Reads the next byte of data from the input stream.
|
int |
read(byte[] buf)
Reads some number of bytes from the input stream and stores them into
the buffer array
b. |
int |
read(byte[] buf,
int off,
int siz)
Reads up to
len bytes of data from the input stream into
an array of bytes. |
byte[] |
readFromCopy()
Blocks wait for a row of data to be received from server on an active copy operation.
|
byte[] |
readFromCopy(boolean block)
Wait for a row of data to be received from server on an active copy operation.
|
mark, markSupported, reset, skippublic PGCopyInputStream(PGConnection connection, String sql) throws SQLException
connection - database connection to use for copying (protocol version 3 required)sql - COPY TO STDOUT statementSQLException - if initializing the operation failspublic PGCopyInputStream(CopyOut op)
op - COPY TO STDOUT operationpublic int available()
throws IOException
java.io.InputStream Note that while some implementations of InputStream will return
the total number of bytes in the stream, many will not. It is
never correct to use the return value of this method to allocate
a buffer intended to hold all data in this stream.
A subclass' implementation of this method may choose to throw an
IOException if this input stream has been closed by
invoking the InputStream.close() method.
The available method for class InputStream always
returns 0.
This method should be overridden by subclasses.
available in class InputStream0 when
it reaches the end of the input stream.IOException - if an I/O error occurs.public int read()
throws IOException
java.io.InputStreamint in the range 0 to
255. If no byte is available because the end of the stream
has been reached, the value -1 is returned. This method
blocks until input data is available, the end of the stream is detected,
or an exception is thrown.
A subclass must provide an implementation of this method.
read in class InputStream-1 if the end of the
stream is reached.IOException - if an I/O error occurs.public int read(byte[] buf)
throws IOException
java.io.InputStreamb. The number of bytes actually read is
returned as an integer. This method blocks until input data is
available, end of file is detected, or an exception is thrown.
If the length of b is zero, then no bytes are read and
0 is returned; otherwise, there is an attempt to read at
least one byte. If no byte is available because the stream is at the
end of the file, the value -1 is returned; otherwise, at
least one byte is read and stored into b.
The first byte read is stored into element b[0], the
next one into b[1], and so on. The number of bytes read is,
at most, equal to the length of b. Let k be the
number of bytes actually read; these bytes will be stored in elements
b[0] through b[k-1],
leaving elements b[k] through
b[b.length-1] unaffected.
The read(b) method for class InputStream
has the same effect as:
read(b, 0, b.length) read in class InputStreambuf - the buffer into which the data is read.-1 if there is no more data because the end of
the stream has been reached.IOException - If the first byte cannot be read for any reason
other than the end of the file, if the input stream has been closed, or
if some other I/O error occurs.InputStream.read(byte[], int, int)public int read(byte[] buf,
int off,
int siz)
throws IOException
java.io.InputStreamlen bytes of data from the input stream into
an array of bytes. An attempt is made to read as many as
len bytes, but a smaller number may be read.
The number of bytes actually read is returned as an integer.
This method blocks until input data is available, end of file is detected, or an exception is thrown.
If len is zero, then no bytes are read and
0 is returned; otherwise, there is an attempt to read at
least one byte. If no byte is available because the stream is at end of
file, the value -1 is returned; otherwise, at least one
byte is read and stored into b.
The first byte read is stored into element b[off], the
next one into b[off+1], and so on. The number of bytes read
is, at most, equal to len. Let k be the number of
bytes actually read; these bytes will be stored in elements
b[off] through b[off+k-1],
leaving elements b[off+k] through
b[off+len-1] unaffected.
In every case, elements b[0] through
b[off] and elements b[off+len] through
b[b.length-1] are unaffected.
The read(b, off, len) method
for class InputStream simply calls the method
read() repeatedly. If the first such call results in an
IOException, that exception is returned from the call to
the read(b, off, len) method. If
any subsequent call to read() results in a
IOException, the exception is caught and treated as if it
were end of file; the bytes read up to that point are stored into
b and the number of bytes read before the exception
occurred is returned. The default implementation of this method blocks
until the requested amount of input data len has been read,
end of file is detected, or an exception is thrown. Subclasses are encouraged
to provide a more efficient implementation of this method.
read in class InputStreambuf - the buffer into which the data is read.off - the start offset in array b
at which the data is written.siz - the maximum number of bytes to read.-1 if there is no more data because the end of
the stream has been reached.IOException - If the first byte cannot be read for any reason
other than end of file, or if the input stream has been closed, or if
some other I/O error occurs.InputStream.read()public byte[] readFromCopy()
throws SQLException
CopyOutreadFromCopy in interface CopyOutSQLException - if something goes wrong for example socket timeoutpublic byte[] readFromCopy(boolean block)
throws SQLException
CopyOutreadFromCopy in interface CopyOutblock - true if need wait data from server otherwise false and will read
pending message from serverSQLException - if something goes wrong for example socket timeoutpublic void close()
throws IOException
java.io.InputStream The close method of InputStream does
nothing.
close in interface Closeableclose in interface AutoCloseableclose in class InputStreamIOException - if an I/O error occurs.public void cancelCopy()
throws SQLException
CopyOperationcancelCopy in interface CopyOperationSQLException - if cancelling failspublic int getFormat()
getFormat in interface CopyOperationpublic int getFieldFormat(int field)
getFieldFormat in interface CopyOperationfield - number of field (0..fieldCount()-1)public int getFieldCount()
getFieldCount in interface CopyOperationpublic boolean isActive()
isActive in interface CopyOperationpublic long getHandledRowCount()
CopyOperationgetHandledRowCount in interface CopyOperationCopyright © 2017 PostgreSQL Global Development Group. All rights reserved.