Package org.apache.calcite.adapter.enumerable

Class NestedBlockBuilderImpl

java.lang.Object

org.apache.calcite.adapter.enumerable.NestedBlockBuilderImpl

All Implemented Interfaces:

NestedBlockBuilder

Direct Known Subclasses:

AggResetContextImpl

public class NestedBlockBuilderImpl
extends java.lang.Object
implements NestedBlockBuilder

Allows to build nested code blocks with tracking of current context and the nullability of particular RexNode expressions.

See Also:

StrictAggImplementor.implementAdd(AggContext, AggAddContext)

Field Summary

Fields

Modifier and Type	Field	Description
private java.util.List<BlockBuilder>	blocks
private java.util.List<java.util.Map<RexNode,java.lang.Boolean>>	nullables

Constructor Summary

Constructors

Constructor	Description
NestedBlockBuilderImpl(BlockBuilder block)	Constructs nested block builders starting of a given code block.

Method Summary

Modifier and Type	Method	Description
BlockBuilder	currentBlock()	Returns the current code block
java.util.Map<RexNode,java.lang.Boolean>	currentNullables()	Returns the current nullability state of rex nodes.
void	exitBlock()	Leaves the current code block.
BlockBuilder	nestBlock()	Starts nested code block.
void	nestBlock(BlockBuilder block)	Uses given block as the new code context.
void	nestBlock(BlockBuilder block, java.util.Map<RexNode,java.lang.Boolean> nullables)	Uses given block as the new code context and the map of nullability.

Methods inherited from class java.lang.Object

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

Field Detail

blocks

private final java.util.List<BlockBuilder> blocks

nullables

private final java.util.List<java.util.Map<RexNode,java.lang.Boolean>> nullables

Constructor Detail

NestedBlockBuilderImpl

public NestedBlockBuilderImpl(BlockBuilder block)

Constructs nested block builders starting of a given code block.

Parameters:

block - root code block

Method Detail

nestBlock

public final BlockBuilder nestBlock()

Starts nested code block. The resulting block can optimize expressions and reuse already calculated values from the parent blocks.

Specified by:

nestBlock in interface NestedBlockBuilder

Returns:

new code block that can optimize expressions and reuse already calculated values from the parent blocks.

nestBlock

public final void nestBlock(BlockBuilder block)

Uses given block as the new code context. The current block will be restored after exitBlock() call.

Specified by:

nestBlock in interface NestedBlockBuilder

Parameters:

block - new code block

See Also:

exitBlock()

nestBlock

public final void nestBlock(BlockBuilder block,
                            java.util.Map<RexNode,java.lang.Boolean> nullables)

Uses given block as the new code context and the map of nullability. The current block will be restored after exitBlock() call.

Specified by:

nestBlock in interface NestedBlockBuilder

Parameters:

block - new code block

nullables - map of expression to its nullability state

See Also:

exitBlock()

currentBlock

public final BlockBuilder currentBlock()

Returns the current code block

Specified by:

currentBlock in interface NestedBlockBuilder

Returns:

current code block

currentNullables

public final java.util.Map<RexNode,java.lang.Boolean> currentNullables()

Returns the current nullability state of rex nodes. The resulting value is the summary of all the maps in the block hierarchy.

Specified by:

currentNullables in interface NestedBlockBuilder

Returns:

current nullability state of rex nodes

exitBlock

public final void exitBlock()

Leaves the current code block.

Specified by:

exitBlock in interface NestedBlockBuilder

See Also:

nestBlock()