//JAVA TO C# CONVERTER WARNING: Method 'throws' clauses are not available in C#:
//ORIGINAL LINE: public void read(RECORD record, org.neo4j.io.pagecache.PageCursor primaryCursor, org.neo4j.kernel.impl.store.record.RecordLoad mode, int recordSize) throws java.io.IOException
public override void Read(RECORD record, PageCursor primaryCursor, RecordLoad mode, int recordSize)
{
int primaryStartOffset = primaryCursor.Offset;
sbyte headerByte = primaryCursor.Byte;
bool inUse = isInUse(headerByte);
bool doubleRecordUnit = has(headerByte, HeaderBitRecordUnit);
record.UseFixedReferences = false;
if (doubleRecordUnit)
{
bool firstRecordUnit = has(headerByte, HeaderBitFirstRecordUnit);
if (!firstRecordUnit)
{
// This is a record unit and not even the first one, so you cannot go here directly and read it,
// it may only be read as part of reading the primary unit.
record.clear();
// Return and try again
primaryCursor.CursorException = "Expected record to be the first unit in the chain, but record header says it's not";
return;
}
// This is a record that is split into multiple record units. We need a bit more clever
// data structures here. For the time being this means instantiating one object,
// but the trade-off is a great reduction in complexity.
long secondaryId = Reference.decode(primaryCursor);
long pageId = pageIdForRecord(secondaryId, primaryCursor.CurrentPageSize, recordSize);
int offset = offsetForId(secondaryId, primaryCursor.CurrentPageSize, recordSize);
PageCursor secondaryCursor = primaryCursor.OpenLinkedCursor(pageId);
if ((!secondaryCursor.Next()) | offset < 0)
{
// We must have made an inconsistent read of the secondary record unit reference.
// No point in trying to read this.
record.clear();
primaryCursor.CursorException = IllegalSecondaryReferenceMessage(pageId);
return;
}
secondaryCursor.Offset = offset + HeaderByte;
int primarySize = recordSize - (primaryCursor.Offset - primaryStartOffset);
// We *could* sanity check the secondary record header byte here, but we won't. If it is wrong, then we most
// likely did an inconsistent read, in which case we'll just retry. Otherwise, if the header byte is wrong,
// then there is little we can do about it here, since we are not allowed to throw exceptions.
int secondarySize = recordSize - HeaderByte;
PageCursor composite = CompositePageCursor.compose(primaryCursor, primarySize, secondaryCursor, secondarySize);
DoReadInternal(record, composite, recordSize, headerByte, inUse);
record.SecondaryUnitId = secondaryId;
}
else
{
record.UseFixedReferences = IsUseFixedReferences(headerByte);
DoReadInternal(record, primaryCursor, recordSize, headerByte, inUse);
}
// Set cursor offset to next record to prepare next read in case of scanning.
primaryCursor.Offset = primaryStartOffset + recordSize;
}
//JAVA TO C# CONVERTER WARNING: Method 'throws' clauses are not available in C#:
//ORIGINAL LINE: public void write(RECORD record, org.neo4j.io.pagecache.PageCursor primaryCursor, int recordSize) throws java.io.IOException
public override void Write(RECORD record, PageCursor primaryCursor, int recordSize)
{
if (record.inUse())
{
// Let the specific implementation provide the additional header bits and we'll provide the core format bits.
sbyte headerByte = HeaderBits(record);
assert(headerByte & 0x7) == 0 : "Format-specific header bits (" + headerByte +
") collides with format-generic header bits";
headerByte = set(headerByte, IN_USE_BIT, record.inUse());
headerByte = set(headerByte, HeaderBitRecordUnit, record.requiresSecondaryUnit());
if (record.requiresSecondaryUnit())
{
headerByte = set(headerByte, HeaderBitFirstRecordUnit, true);
}
else
{
headerByte = set(headerByte, HeaderBitFixedReference, !record.UseFixedReferences);
}
primaryCursor.PutByte(headerByte);
if (record.requiresSecondaryUnit())
{
// Write using the normal adapter since the first reference we write cannot really overflow
// into the secondary record
long secondaryUnitId = record.SecondaryUnitId;
long pageId = pageIdForRecord(secondaryUnitId, primaryCursor.CurrentPageSize, recordSize);
int offset = offsetForId(secondaryUnitId, primaryCursor.CurrentPageSize, recordSize);
PageCursor secondaryCursor = primaryCursor.OpenLinkedCursor(pageId);
if (!secondaryCursor.Next())
{
// We are not allowed to write this much data to the file, apparently.
record.clear();
return;
}
secondaryCursor.Offset = offset;
secondaryCursor.PutByte(( sbyte )(IN_USE_BIT | HeaderBitRecordUnit));
int recordSizeWithoutHeader = recordSize - HeaderByte;
PageCursor composite = CompositePageCursor.compose(primaryCursor, recordSizeWithoutHeader, secondaryCursor, recordSizeWithoutHeader);
Reference.encode(secondaryUnitId, composite);
DoWriteInternal(record, composite);
}
else
{
DoWriteInternal(record, primaryCursor);
}
}
else
{
MarkAsUnused(primaryCursor, record, recordSize);
}
}
