org.openanzo.glitter.util
Class Glitter

java.lang.Object
  org.openanzo.glitter.util.Glitter

public class Glitter
extends java.lang.Object

The Glitter class provides a variety of static utility methods.

Author:

lee

Method Summary

static java.net.URI	createURI(java.lang.String s) Synonym for URI.create(String).
static org.apache.commons.logging.Log	getLog() Provides access to a common log.
static java.lang.String	getReadableQueryPlan(TreeNode n, QueryExecutionPlan plan) Pretty-printer for QueryExecutionPlan.
static boolean	isUsedOutsideOfNode(Bindable b, TreeNode n, QueryInformation qc) Tests if a given variable (or blank node) appears in the query outside of a given node and its descendants.
static TreeNode	rewriteTree(TreeNode node, TreeRewriter rewriter) Implements a post-order traversal which rewrites tree nodes.

Methods inherited from class java.lang.Object

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

Method Detail

getLog

public static org.apache.commons.logging.Log getLog()

Provides access to a common log.

Returns:

the common log for Glitter

createURI

public static java.net.URI createURI(java.lang.String s)

Synonym for URI.create(String).

Parameters:

s - String representation of URI

Returns:

the URI representation of the given string

getReadableQueryPlan

public static java.lang.String getReadableQueryPlan(TreeNode n,
                                                    QueryExecutionPlan plan)

Pretty-printer for QueryExecutionPlan.

Parameters:

n - The root node for query planning.

plan - The plan.

Returns:

A human-readable string explaining the query plan.

rewriteTree

public static TreeNode rewriteTree(TreeNode node,
                                   TreeRewriter rewriter)

Implements a post-order traversal which rewrites tree nodes.

Parameters:

node - The root of the nodes to rewrite.

rewriter - A TreeRewriter that examines each node.

Returns:

null, if node should be removed. Otherwise, the return value is substituted in-plcae for node in the query tree.

isUsedOutsideOfNode

public static boolean isUsedOutsideOfNode(Bindable b,
                                          TreeNode n,
                                          QueryInformation qc)

Tests if a given variable (or blank node) appears in the query outside of a given node and its descendants.

Parameters:

b - The variable or blank node to test.

n - The root node of the tree segment that should be excluded from a search

qc - The QueryInformation that provides a look at the entire query

Returns:

true if the given variable appears in the query outside of a given node and its descendants.