org.apache.phoenix.schema.KeyValueSchema Maven / Gradle / Ivy
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* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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 org.apache.phoenix.schema;
import java.util.List;
import org.apache.hadoop.hbase.io.ImmutableBytesWritable;
import org.apache.hadoop.io.WritableUtils;
import org.apache.http.annotation.Immutable;
import org.apache.phoenix.exception.SQLExceptionCode;
import org.apache.phoenix.exception.SQLExceptionInfo;
import org.apache.phoenix.expression.Expression;
import org.apache.phoenix.schema.tuple.Tuple;
import org.apache.phoenix.schema.types.PDataType;
import org.apache.phoenix.util.ByteUtil;
/**
*
* Simple flat schema over a byte array where fields may be any of {@link org.apache.phoenix.schema.types.PDataType}.
* Optimized for positional access by index.
*
*
* @since 0.1
*/
@Immutable
public class KeyValueSchema extends ValueSchema {
public KeyValueSchema() {
}
protected KeyValueSchema(int minNullable, List fields) {
super(minNullable, fields);
}
public static class KeyValueSchemaBuilder extends ValueSchemaBuilder {
public KeyValueSchemaBuilder(int minNullable) {
super(minNullable);
}
@Override
public KeyValueSchema build() {
List condensedFields = buildFields();
return new KeyValueSchema(this.minNullable, condensedFields);
}
@Override
public KeyValueSchemaBuilder setMaxFields(int nFields) {
super.setMaxFields(nFields);
return this;
}
public KeyValueSchemaBuilder addField(PDatum datum) {
super.addField(datum, fields.size() >= this.minNullable, SortOrder.getDefault());
return this;
}
}
public boolean isNull(int position, ValueBitSet bitSet) {
int nBit = position - getMinNullable();
return (nBit >= 0 && !bitSet.get(nBit));
}
private static byte[] ensureSize(byte[] b, int offset, int size) {
if (size > b.length) {
byte[] bBigger = new byte[Math.max(b.length * 2, size)];
System.arraycopy(b, 0, bBigger, 0, b.length);
return bBigger;
}
return b;
}
/**
* @return byte representation of the KeyValueSchema
*/
public byte[] toBytes(Expression[] expressions, ValueBitSet valueSet, ImmutableBytesWritable ptr) {
return toBytes(null, expressions, valueSet, ptr);
}
/**
* @return byte representation of the KeyValueSchema
*/
public byte[] toBytes(Tuple tuple, Expression[] expressions, ValueBitSet valueSet, ImmutableBytesWritable ptr) {
int offset = 0;
int index = 0;
valueSet.clear();
int minNullableIndex = getMinNullable();
byte[] b = new byte[getEstimatedValueLength() + valueSet.getEstimatedLength()];
List fields = getFields();
// We can get away with checking if only nulls are left in the outer loop,
// since repeating fields will not span the non-null/null boundary.
for (int i = 0; i < fields.size(); i++) {
Field field = fields.get(i);
PDataType type = field.getDataType();
for (int j = 0; j < field.getCount(); j++) {
if (expressions[index].evaluate(tuple, ptr) && ptr.getLength() > 0) { // Skip null values
if (index >= minNullableIndex) {
valueSet.set(index - minNullableIndex);
}
if (!type.isFixedWidth()) {
b = ensureSize(b, offset, offset + getVarLengthBytes(ptr.getLength()));
offset = writeVarLengthField(ptr, b, offset);
} else {
int nBytes = ptr.getLength();
b = ensureSize(b, offset, offset + nBytes);
System.arraycopy(ptr.get(), ptr.getOffset(), b, offset, nBytes);
offset += nBytes;
}
}
index++;
}
}
// Add information about which values were set at end of value,
// so that we can quickly access them without needing to walk
// through the values using the schema.
// TODO: if there aren't any non null values, don't serialize anything
b = ensureSize(b, offset, offset + valueSet.getEstimatedLength());
offset = valueSet.toBytes(b, offset);
if (offset == b.length) {
return b;
} else {
byte[] bExact = new byte[offset];
System.arraycopy(b, 0, bExact, 0, offset);
return bExact;
}
}
private int getVarLengthBytes(int length) {
return length + WritableUtils.getVIntSize(length);
}
private int writeVarLengthField(ImmutableBytesWritable ptr, byte[] b, int offset) {
int length = ptr.getLength();
offset += ByteUtil.vintToBytes(b, offset, length);
System.arraycopy(ptr.get(), ptr.getOffset(), b, offset, length);
offset += length;
return offset;
}
@edu.umd.cs.findbugs.annotations.SuppressWarnings(
value="NP_BOOLEAN_RETURN_NULL",
justification="Designed to return null.")
public Boolean iterator(byte[] src, int srcOffset, int srcLength, ImmutableBytesWritable ptr, int position, ValueBitSet valueBitSet) {
ptr.set(src, srcOffset, 0);
int maxOffset = srcOffset + srcLength;
Boolean hasValue = null;
for (int i = 0; i < position; i++) {
hasValue = next(ptr, i, maxOffset, valueBitSet);
}
return hasValue;
}
public Boolean iterator(ImmutableBytesWritable srcPtr, ImmutableBytesWritable ptr, int position, ValueBitSet valueSet) {
return iterator(srcPtr.get(),srcPtr.getOffset(),srcPtr.getLength(), ptr, position, valueSet);
}
public Boolean iterator(ImmutableBytesWritable ptr, int position, ValueBitSet valueSet) {
return iterator(ptr, ptr, position, valueSet);
}
public Boolean iterator(ImmutableBytesWritable ptr) {
return iterator(ptr, ptr, 0, ValueBitSet.EMPTY_VALUE_BITSET);
}
/**
* Move the bytes ptr to the next position relative to the current ptr
* @param ptr bytes pointer pointing to the value at the positional index
* provided.
* @param position zero-based index of the next field in the value schema
* @param maxOffset max possible offset value when iterating
* @return true if a value was found and ptr was set, false if the value is null and ptr was not
* set, and null if the value is null and there are no more values
*/
@edu.umd.cs.findbugs.annotations.SuppressWarnings(
value="NP_BOOLEAN_RETURN_NULL",
justification="Designed to return null.")
public Boolean next(ImmutableBytesWritable ptr, int position, int maxOffset, ValueBitSet valueSet) {
if (ptr.getOffset() + ptr.getLength() >= maxOffset) {
ptr.set(ptr.get(), maxOffset, 0);
return null;
}
if (position >= getFieldCount()) {
return null;
}
// Move the pointer past the current value and set length
// to 0 to ensure you never set the ptr past the end of the
// backing byte array.
ptr.set(ptr.get(), ptr.getOffset() + ptr.getLength(), 0);
if (!isNull(position, valueSet)) {
Field field = this.getField(position);
int length = field.getDataType().isFixedWidth() ?
field.getByteSize() : ByteUtil.vintFromBytes(ptr);
if (ptr.getOffset() + length > maxOffset) {
throw new RuntimeException(new SQLExceptionInfo.Builder(SQLExceptionCode.ILLEGAL_DATA)
.setMessage("Expected length of at least " + length + " bytes, but had " + (maxOffset
- ptr.getOffset())).build().buildException());
}
ptr.set(ptr.get(),ptr.getOffset(),length);
return ptr.getLength() > 0;
}
return false;
}
}
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