org.apache.hadoop.hive.metastore.parser

Class ExpressionTree

java.lang.Object

org.apache.hadoop.hive.metastore.parser.ExpressionTree

public class ExpressionTree
extends Object

The Class representing the filter as a binary tree. The tree has TreeNode's at intermediate level and the leaf level nodes are of type LeafNode.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	ExpressionTree.ANTLRNoCaseStringStream Case insensitive ANTLR string stream
static class	ExpressionTree.FilterBuilder Helper class that wraps the stringbuilder used to build the filter over the tree, as well as error propagation in two modes - expect errors, i.e.
static class	ExpressionTree.LeafNode The Class representing the leaf level nodes in the ExpressionTree.
static class	ExpressionTree.LogicalOperator The logical operations supported.
static class	ExpressionTree.Operator The operators supported.
static class	ExpressionTree.TreeNode The Class representing a Node in the ExpressionTree.
static class	ExpressionTree.TreeVisitor Depth first traversal of ExpressionTree.

Field Summary

Fields

Modifier and Type	Field and Description
static ExpressionTree	EMPTY_TREE The empty tree that can be returned for an empty filter.

Constructor Summary

Constructors

Constructor and Description
ExpressionTree()

Method Summary

Methods

Modifier and Type	Method and Description
void	accept(ExpressionTree.TreeVisitor treeVisitor)
void	addIntermediateNode(ExpressionTree.LogicalOperator andOr) Adds a intermediate node of either type(AND/OR).
void	addLeafNode(ExpressionTree.LeafNode newNode) Adds a leaf node, pushes the new node onto the stack.
void	generateJDOFilterFragment(org.apache.hadoop.conf.Configuration conf, Table table, Map<String,Object> params, ExpressionTree.FilterBuilder filterBuilder) Generate the JDOQL filter for the given expression tree
ExpressionTree.TreeNode	getRoot()

Methods inherited from class java.lang.Object

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

Field Detail

EMPTY_TREE

public static final ExpressionTree EMPTY_TREE

The empty tree that can be returned for an empty filter.

Constructor Detail

ExpressionTree

public ExpressionTree()

Method Detail

accept

public void accept(ExpressionTree.TreeVisitor treeVisitor)
            throws MetaException

Throws:

MetaException

getRoot

public ExpressionTree.TreeNode getRoot()

addIntermediateNode

public void addIntermediateNode(ExpressionTree.LogicalOperator andOr)

Adds a intermediate node of either type(AND/OR). Pops last two nodes from the stack and sets them as children of the new node and pushes itself onto the stack.

Parameters:

andOr - the operator type

addLeafNode

public void addLeafNode(ExpressionTree.LeafNode newNode)

Adds a leaf node, pushes the new node onto the stack.

Parameters:

newNode - the new node

generateJDOFilterFragment

public void generateJDOFilterFragment(org.apache.hadoop.conf.Configuration conf,
                             Table table,
                             Map<String,Object> params,
                             ExpressionTree.FilterBuilder filterBuilder)
                               throws MetaException

Generate the JDOQL filter for the given expression tree

Parameters:

table - the table being queried

params - the input map which is updated with the the parameterized values. Keys are the parameter names and values are the parameter values

filterBuilder - the filter builder to append to.

Throws:

MetaException