Package org.apache.juneau.marshall.stream

Class StreamingArrayRecord

java.lang.Object

org.apache.juneau.marshall.stream.StreamingArrayRecord

public final class StreamingArrayRecord
extends Object

O(1)-memory wrappers that adapt a fine-grained TokenReader / TokenWriter to the array-element record-stream contract. Memory does not scale with the number of array elements — reading binds one element at a time; writing emits one element at a time.

For the reader: the wrapper opens an outer array via the cursor's TokenReader.next(), yields elements via TokenReader.read(Class) until TokenReader.canRead() returns false (end of array), then advances past the closing ] on close.

For the writer: the wrapper opens an outer array via TokenWriter.startArray(), forwards each write(...) call to TokenWriter.object(Object), and emits the closing ] via TokenWriter.endArray() on close.

Used by FULL-capability formats whose token cursor genuinely streams (json, json5, cbor, etc.). For PARTIAL formats whose token surface doesn't exist, see RecordAdapter.arrayReader(ParserSession, Object) / RecordAdapter.arrayWriter(org.apache.juneau.marshall.serializer.SerializerSession, java.lang.Object), which are buffered.

Method Summary

Modifier and Type	Method	Description
static RecordReader	reader(TokenReader cursor)	Wraps a TokenReader as a streaming array-element RecordReader.
static RecordWriter	writer(TokenWriter cursor)	Wraps a TokenWriter as a streaming array-element RecordWriter.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Details

reader

public static RecordReader reader(TokenReader cursor)
                           throws IOException,
ParseException

Wraps a TokenReader as a streaming array-element RecordReader.

The wrapper assumes the cursor is positioned at the start of an array on the wire. It consumes the opening TokenType.START_ARRAY on construction and the closing TokenType.END_ARRAY on close().

Parameters:

cursor - The token reader to wrap. Must not be null. Owned by the returned RecordReader; closing the RecordReader closes the cursor.

Returns:

A streaming array-element RecordReader.

Throws:

IOException - If a problem occurred reading the underlying input.

ParseException - If the input is not a JSON-style array.

writer

public static RecordWriter writer(TokenWriter cursor)
                           throws IOException

Wraps a TokenWriter as a streaming array-element RecordWriter.

The wrapper emits the opening array on construction. Each RecordWriter.write(Object) call appends one array element via TokenWriter.object(Object). close() emits the closing array bracket and closes the underlying cursor.

Parameters:

cursor - The token writer to wrap. Must not be null. Owned by the returned RecordWriter; closing the RecordWriter closes the cursor.

Returns:

A streaming array-element RecordWriter.

Throws:

IOException - If a problem occurred writing to the underlying output.