public class BlockingBinaryEncoder extends BufferedBinaryEncoder
BinaryEncoder
implementation that writes large arrays and maps as a
sequence of blocks. So long as individual primitive values fit in memory,
arbitrarily long arrays and maps may be written and subsequently read without
exhausting memory. Values are buffered until the specified block size would
be exceeded, minimizing block overhead.
Use EncoderFactory.blockingBinaryEncoder(OutputStream, BinaryEncoder)
to construct and configure.
BlockingBinaryEncoder buffers writes, data may not appear on the output until
flush()
is called.
BlockingBinaryEncoder is not thread-safeBinaryEncoder
,
EncoderFactory
,
Encoder
Modifier and Type | Method and Description |
---|---|
int |
bytesBuffered()
Returns the number of bytes currently buffered by this encoder.
|
void |
flush() |
void |
setItemCount(long itemCount)
Call this method before writing a batch of items in an array or a map.
|
void |
startItem()
Start a new item of an array or map.
|
void |
writeArrayEnd()
Call this method to finish writing an array.
|
void |
writeArrayStart()
Call this method to start writing an array.
|
void |
writeBoolean(boolean b)
Write a boolean value.
|
void |
writeDouble(double d)
Write a double.
|
void |
writeFixed(byte[] bytes,
int start,
int len)
Writes a fixed size binary object.
|
void |
writeFloat(float f)
Write a float.
|
void |
writeIndex(int unionIndex)
Call this method to write the tag of a union.
|
void |
writeInt(int n)
Writes a 32-bit integer.
|
void |
writeLong(long n)
Write a 64-bit integer.
|
void |
writeMapEnd()
Call this method to terminate the inner-most, currently-opened
map.
|
void |
writeMapStart()
Call this to start a new map.
|
protected void |
writeZero()
Write a zero byte to the underlying output.
|
writeFixed
writeBytes, writeBytes, writeEnum, writeNull, writeString, writeString
writeBytes, writeFixed, writeString
public void flush() throws IOException
flush
in interface Flushable
flush
in class BufferedBinaryEncoder
IOException
public void writeBoolean(boolean b) throws IOException
Encoder
writeBoolean
in class BufferedBinaryEncoder
IOException
public void writeInt(int n) throws IOException
Encoder
writeInt
in class BufferedBinaryEncoder
IOException
public void writeLong(long n) throws IOException
Encoder
writeLong
in class BufferedBinaryEncoder
IOException
public void writeFloat(float f) throws IOException
Encoder
writeFloat
in class BufferedBinaryEncoder
IOException
public void writeDouble(double d) throws IOException
Encoder
writeDouble
in class BufferedBinaryEncoder
IOException
public void writeFixed(byte[] bytes, int start, int len) throws IOException
Encoder
writeFixed
in class BufferedBinaryEncoder
bytes
- The contents to writestart
- The position within bytes where the contents
start.len
- The number of bytes to write.IOException
protected void writeZero() throws IOException
BinaryEncoder
writeZero
in class BufferedBinaryEncoder
IOException
public void writeArrayStart() throws IOException
Encoder
Encoder.writeArrayStart()
. Then, before writing any data for any item
call Encoder.setItemCount(long)
followed by a sequence of
Encoder.startItem()
and the item itself. The number of
Encoder.startItem()
should match the number specified in
Encoder.setItemCount(long)
.
When actually writing the data of the item, you can call any Encoder
method (e.g., Encoder.writeLong(long)
). When all items
of the array have been written, call Encoder.writeArrayEnd()
.
As an example, let's say you want to write an array of records,
the record consisting of an Long field and a Boolean field.
Your code would look something like this:
out.writeArrayStart(); out.setItemCount(list.size()); for (Record r : list) { out.startItem(); out.writeLong(r.longField); out.writeBoolean(r.boolField); } out.writeArrayEnd();
writeArrayStart
in class BinaryEncoder
IOException
public void setItemCount(long itemCount) throws IOException
Encoder
Encoder.startItem()
followed by any of the
other write methods of Encoder
. The number of calls
to Encoder.startItem()
must be equal to the count specified
in Encoder.setItemCount(long)
. Once a batch is completed you
can start another batch with Encoder.setItemCount(long)
.setItemCount
in class BinaryEncoder
itemCount
- The number of Encoder.startItem()
calls to follow.IOException
public void startItem() throws IOException
Encoder
Encoder.writeArrayStart()
for usage information.startItem
in class BinaryEncoder
IOException
public void writeArrayEnd() throws IOException
Encoder
Encoder.writeArrayStart()
for usage information.writeArrayEnd
in class BinaryEncoder
IOException
public void writeMapStart() throws IOException
Encoder
Encoder.writeArrayStart()
for details on usage.
As an example of usage, let's say you want to write a map of
records, the record consisting of an Long field and a Boolean
field. Your code would look something like this:
out.writeMapStart(); out.setItemCount(list.size()); for (Map.Entryentry : map.entrySet()) { out.startItem(); out.writeString(entry.getKey()); out.writeLong(entry.getValue().longField); out.writeBoolean(entry.getValue().boolField); } out.writeMapEnd();
writeMapStart
in class BinaryEncoder
IOException
public void writeMapEnd() throws IOException
Encoder
Encoder.writeArrayStart()
for more details.writeMapEnd
in class BinaryEncoder
IOException
public void writeIndex(int unionIndex) throws IOException
Encoder
out.writeIndex(1); out.writeLong(record.longField); out.writeBoolean(record.boolField);
writeIndex
in class BinaryEncoder
IOException
public int bytesBuffered()
BinaryEncoder
Flushable.flush()
to empty the buffer to the underlying output.bytesBuffered
in class BufferedBinaryEncoder
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