/*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.facebook.presto.jdbc.internal.type.block;
import com.facebook.presto.jdbc.internal.airlift.slice.SizeOf;
import com.facebook.presto.jdbc.internal.airlift.slice.Slice;
import java.util.Arrays;
public class LazyFixedWidthBlock
extends AbstractFixedWidthBlock
{
private final int positionCount;
private final LazyFixedWidthBlockLoader loader;
private Slice slice;
private boolean[] valueIsNull;
private boolean released;
public LazyFixedWidthBlock(int fixedSize, int positionCount, LazyFixedWidthBlockLoader loader)
{
super(fixedSize);
if (positionCount < 0) {
throw new IllegalArgumentException("positionCount is negative");
}
this.positionCount = positionCount;
if (loader == null) {
throw new IllegalArgumentException("loader is null");
}
this.loader = loader;
}
LazyFixedWidthBlock(int fixedSize, int positionCount, LazyFixedWidthBlockLoader loader, Slice slice, boolean[] valueIsNull)
{
super(fixedSize);
this.positionCount = positionCount;
this.loader = loader;
this.slice = slice;
this.valueIsNull = valueIsNull;
}
@Override
protected Slice getRawSlice()
{
assureLoaded();
return slice;
}
@Override
protected boolean isEntryNull(int position)
{
assureLoaded();
return valueIsNull[position];
}
@Override
public int getPositionCount()
{
return positionCount;
}
@Override
public int getSizeInBytes()
{
long size = (positionCount * fixedSize) + SizeOf.sizeOf(valueIsNull);
if (size > Integer.MAX_VALUE) {
return Integer.MAX_VALUE;
}
return (int) size;
}
@Override
public Block getRegion(int positionOffset, int length)
{
if (positionOffset < 0 || length < 0 || positionOffset + length > positionCount) {
throw new IndexOutOfBoundsException("Invalid position " + positionOffset + " in block with " + positionCount + " positions");
}
assureLoaded();
Slice newSlice = slice.slice(positionOffset * fixedSize, length * fixedSize);
return new LazyFixedWidthBlock(fixedSize, length, loader, newSlice, Arrays.copyOfRange(valueIsNull, positionOffset, positionOffset + length));
}
@Override
public void release()
{
if (released) {
return;
}
released = true;
loader.release();
}
private void assureLoaded()
{
if (slice != null) {
return;
}
if (released) {
throw new IllegalArgumentException("block has been released");
}
loader.load(this);
}
public void setRawSlice(Slice slice)
{
if (slice.length() < positionCount * fixedSize) {
throw new IllegalArgumentException("slice is not large enough to hold all positions");
}
this.slice = slice;
}
public void setNullVector(boolean[] valueIsNull)
{
if (valueIsNull.length < positionCount) {
throw new IllegalArgumentException("valueIsNull length is less than positionCount");
}
this.valueIsNull = valueIsNull;
}
@Override
public String toString()
{
StringBuilder sb = new StringBuilder("FixedWidthBlock{");
sb.append("positionCount=").append(positionCount);
sb.append(", slice=").append(slice == null ? "not loaded" : slice);
sb.append('}');
return sb.toString();
}
public interface LazyFixedWidthBlockLoader
{
void load(LazyFixedWidthBlock block);
void release();
}
}