提交 279d0515 authored 作者: noelgrandin's avatar noelgrandin

bit-pack the not-null indicators to save a little space

上级 86c59286
......@@ -1533,16 +1533,70 @@ public class TransactionStore {
@Override
public void read(ByteBuffer buff, Object[] obj,
int len, boolean key) {
// Read the operationIds
for (int i = 0; i < len; i++) {
obj[i] = read(buff);
VersionedValue v = new VersionedValue();
v.operationId = DataUtils.readVarLong(buff);
obj[i] = v;
}
// Read the null/not-null indicators.
final byte[] notNullIndicators = new byte[(len + 7) / 8];
buff.get(notNullIndicators, 0, notNullIndicators.length);
// Read the child values.
for (int i = 0; i < len; i++) {
VersionedValue v = (VersionedValue) obj[i];
int x = notNullIndicators[i / 8] & 0xff;
x = x >> (i % 8);
x = x & 1;
if (x == 1) {
v.value = valueType.read(buff);
}
}
}
@Override
public Object read(ByteBuffer buff) {
VersionedValue v = new VersionedValue();
v.operationId = DataUtils.readVarLong(buff);
if (buff.get() == 1) {
v.value = valueType.read(buff);
}
return v;
}
@Override
public void write(WriteBuffer buff, Object[] obj,
int len, boolean key) {
// Write the operationIds
for (int i = 0; i < len; i++) {
VersionedValue v = (VersionedValue) obj[i];
buff.putVarLong(v.operationId);
}
// Write the not-null-indicators as a bit-packed array
int x = 0;
int byteIdx = 0;
for (int i = 0; i < len; i++) {
VersionedValue v = (VersionedValue) obj[i];
if (v.value != null) {
x |= 1 << byteIdx;
}
byteIdx++;
if (byteIdx == 8) {
buff.put((byte) x);
byteIdx = 0;
x = 0;
}
}
if (byteIdx != 0) {
buff.put((byte) x);
}
// Write the child values.
for (int i = 0; i < len; i++) {
write(buff, obj[i]);
VersionedValue v = (VersionedValue) obj[i];
if (v.value != null) {
valueType.write(buff, v.value);
}
}
}
......@@ -1558,16 +1612,6 @@ public class TransactionStore {
}
}
@Override
public Object read(ByteBuffer buff) {
VersionedValue v = new VersionedValue();
v.operationId = DataUtils.readVarLong(buff);
if (buff.get() == 1) {
v.value = valueType.read(buff);
}
return v;
}
}
/**
......@@ -1618,16 +1662,56 @@ public class TransactionStore {
@Override
public void read(ByteBuffer buff, Object[] obj,
int len, boolean key) {
// Read the not-null-indicators.
final byte[] notNullIndicators = new byte[(len * arrayLength + 7) / 8];
buff.get(notNullIndicators, 0, notNullIndicators.length);
// Read the values.
for (int i = 0; i < len; i++) {
obj[i] = read(buff);
Object[] array = new Object[arrayLength];
obj[i] = array;
for (int j = 0; j < arrayLength; j++) {
int x = notNullIndicators[(i * arrayLength + j) / 8] & 0xff;
x = x >> ((i * arrayLength + j) % 8);
x = x & 1;
if (x == 1) {
array[j] = elementTypes[j].read(buff);
}
}
}
}
@Override
public void write(WriteBuffer buff, Object[] obj,
int len, boolean key) {
// Write the null/not-null indicators as a bit-packed array
int x = 0;
int byteIdx = 0;
for (int i = 0; i < len; i++) {
Object[] array = (Object[]) obj[i];
for (int j = 0; j < arrayLength; j++) {
if (array[j] != null) {
x |= 1 << byteIdx;
}
byteIdx++;
if (byteIdx == 8) {
buff.put((byte) x);
byteIdx = 0;
x = 0;
}
}
}
if (byteIdx != 0) {
buff.put((byte) x);
}
// Write the values.
for (int i = 0; i < len; i++) {
write(buff, obj[i]);
Object[] array = (Object[]) obj[i];
for (int j = 0; j < arrayLength; j++) {
if (array[j] != null) {
elementTypes[j].write(buff, array[j]);
}
}
}
}
......
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