org.apache.derby.impl.sql.compile
Class StaticClassFieldReferenceNode

java.lang.Object
  org.apache.derby.impl.sql.compile.QueryTreeNode
      org.apache.derby.impl.sql.compile.JavaValueNode
          org.apache.derby.impl.sql.compile.StaticClassFieldReferenceNode

All Implemented Interfaces:

Node, Visitable

public final class StaticClassFieldReferenceNode
extends JavaValueNode

A StaticClassFieldReferenceNode represents a Java static field reference from a Class (as opposed to an Object). Field references can be made in DML (as expressions).

Field Summary

private boolean	classNameDelimitedIdentifier
private java.lang.reflect.Member	field The field we are going to access.
private java.lang.String	fieldName
private java.lang.String	javaClassName

Fields inherited from class org.apache.derby.impl.sql.compile.JavaValueNode

forCallStatement, jsqlType

Fields inherited from class org.apache.derby.impl.sql.compile.QueryTreeNode

AUTOINCREMENT_CREATE_MODIFY, AUTOINCREMENT_INC_INDEX, AUTOINCREMENT_IS_AUTOINCREMENT_INDEX, AUTOINCREMENT_START_INDEX, isPrivilegeCollectionRequired

Constructor Summary

StaticClassFieldReferenceNode()

Method Summary

JavaValueNode	bindExpression(FromList fromList, SubqueryList subqueryList, java.util.List aggregateVector) Bind this expression.
boolean	categorize(JBitSet referencedTabs, boolean simplePredsOnly) Categorize this predicate.
void	generateExpression(ExpressionClassBuilder acb, MethodBuilder mb) General logic shared by Core compilation and by the Replication Filter compiler.
protected int	getOrderableVariantType() Return the variant type for the underlying expression.
void	init(java.lang.Object javaClassName, java.lang.Object fieldName, java.lang.Object classNameDelimitedIdentifier) Initializer for a StaticClassFieldReferenceNode
void	preprocess(int numTables, FromList outerFromList, SubqueryList outerSubqueryList, PredicateList outerPredicateList) Preprocess an expression tree.
JavaValueNode	remapColumnReferencesToExpressions() Remap all ColumnReferences in this tree to be clones of the underlying expression.

Methods inherited from class org.apache.derby.impl.sql.compile.JavaValueNode

castToPrimitive, checkReliability, generate, generateReceiver, generateReceiver, getCollationType, getConstantValueAsObject, getDataType, getJavaTypeName, getJSQLType, getPrimitiveTypeName, getReceiverExpression, isPrimitiveType, mapToTypeID, markForCallStatement, markReturnValueDiscarded, mustCastToPrimitive, returnValueDiscarded, returnValueToSQLDomain, setCollationType, setJavaTypeName, valueReturnedToSQLDomain

Methods inherited from class org.apache.derby.impl.sql.compile.QueryTreeNode

accept, acceptChildren, bindOffsetFetch, bindRowMultiSet, bindUserCatalogType, bindUserType, checkReliability, checkReliability, convertDefaultNode, createTypeDependency, debugFlush, debugPrint, disablePrivilegeCollection, formatNodeString, foundString, generateAuthorizeCheck, getBeginOffset, getClassFactory, getCompilerContext, getContextManager, getCursorInfo, getDataDictionary, getDependencyManager, getEndOffset, getExecutionFactory, getGenericConstantActionFactory, getIntProperty, getLanguageConnectionContext, getNodeFactory, getNodeType, getNullNode, getParameterTypes, getSchemaDescriptor, getSchemaDescriptor, getStatementType, getTableDescriptor, getTypeCompiler, init, init, init, init, init, init, init, init, init, init, init, init, init, isAtomic, isInstanceOf, isPrivilegeCollectionRequired, isSessionSchema, isSessionSchema, makeConstantAction, makeTableName, makeTableName, nodeHeader, orReliability, parseStatement, printLabel, printSubNodes, referencesSessionSchema, resolveTableToSynonym, setBeginOffset, setContextManager, setEndOffset, setNodeType, setRefActionInfo, stackPrint, toString, treePrint, treePrint, verifyClassExist

Methods inherited from class java.lang.Object

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

Field Detail

fieldName

private java.lang.String fieldName

javaClassName

private java.lang.String javaClassName

classNameDelimitedIdentifier

private boolean classNameDelimitedIdentifier

field

private java.lang.reflect.Member field

The field we are going to access.

Constructor Detail

StaticClassFieldReferenceNode

public StaticClassFieldReferenceNode()

Method Detail

init

public void init(java.lang.Object javaClassName,
                 java.lang.Object fieldName,
                 java.lang.Object classNameDelimitedIdentifier)

Initializer for a StaticClassFieldReferenceNode

Specified by:

init in interface Node

Overrides:

init in class QueryTreeNode

Parameters:

javaClassName - The class name

fieldName - The field name

bindExpression

public JavaValueNode bindExpression(FromList fromList,
                                    SubqueryList subqueryList,
                                    java.util.List aggregateVector)
                             throws StandardException

Bind this expression. This means binding the sub-expressions, as well as figuring out what the return type is for this expression.

Specified by:

bindExpression in class JavaValueNode

Parameters:

fromList - The FROM list for the query this expression is in, for binding columns.

subqueryList - The subquery list being built as we find SubqueryNodes

aggregateVector - The aggregate vector being built as we find AggregateNodes

Returns:

Nothing

Throws:

StandardException - Thrown on error

See Also:

ValueNode.bindExpression(org.apache.derby.impl.sql.compile.FromList, org.apache.derby.impl.sql.compile.SubqueryList, java.util.List)

preprocess

public void preprocess(int numTables,
                       FromList outerFromList,
                       SubqueryList outerSubqueryList,
                       PredicateList outerPredicateList)
                throws StandardException

Preprocess an expression tree. We do a number of transformations here (including subqueries, IN lists, LIKE and BETWEEN) plus subquery flattening. NOTE: This is done before the outer ResultSetNode is preprocessed.

Specified by:

preprocess in class JavaValueNode

Parameters:

numTables - Number of tables in the DML Statement

outerFromList - FromList from outer query block

outerSubqueryList - SubqueryList from outer query block

outerPredicateList - PredicateList from outer query block

Throws:

StandardException - Thrown on error

See Also:

ValueNode.preprocess(int, org.apache.derby.impl.sql.compile.FromList, org.apache.derby.impl.sql.compile.SubqueryList, org.apache.derby.impl.sql.compile.PredicateList)

categorize

public boolean categorize(JBitSet referencedTabs,
                          boolean simplePredsOnly)

Categorize this predicate. Initially, this means building a bit map of the referenced tables for each predicate. If the source of this ColumnReference (at the next underlying level) is not a ColumnReference or a VirtualColumnNode then this predicate will not be pushed down. For example, in: select * from (select 1 from s) a (x) where x = 1 we will not push down x = 1. NOTE: It would be easy to handle the case of a constant, but if the inner SELECT returns an arbitrary expression, then we would have to copy that tree into the pushed predicate, and that tree could contain subqueries and method calls. RESOLVE - revisit this issue once we have views.

Specified by:

categorize in class JavaValueNode

Parameters:

referencedTabs - JBitSet with bit map of referenced FromTables

simplePredsOnly - Whether or not to consider method calls, field references and conditional nodes when building bit map

Returns:

boolean Whether or not source.expression is a ColumnReference or a VirtualColumnNode.

See Also:

ValueNode.categorize(org.apache.derby.iapi.util.JBitSet, boolean)

remapColumnReferencesToExpressions

public JavaValueNode remapColumnReferencesToExpressions()
                                                 throws StandardException

Remap all ColumnReferences in this tree to be clones of the underlying expression.

Specified by:

remapColumnReferencesToExpressions in class JavaValueNode

Returns:

JavaValueNode The remapped expression tree.

Throws:

StandardException - Thrown on error

See Also:

ValueNode.remapColumnReferencesToExpressions()

getOrderableVariantType

protected int getOrderableVariantType()

Return the variant type for the underlying expression. The variant type can be: VARIANT - variant within a scan (method calls and non-static field access) SCAN_INVARIANT - invariant within a scan (column references from outer tables) QUERY_INVARIANT - invariant within the life of a query CONSTANT - constant

Overrides:

getOrderableVariantType in class JavaValueNode

Returns:

The variant type for the underlying expression.

generateExpression

public void generateExpression(ExpressionClassBuilder acb,
                               MethodBuilder mb)
                        throws StandardException

Description copied from class: JavaValueNode

General logic shared by Core compilation and by the Replication Filter compiler. Every child of ValueNode must implement one of these methods.

Specified by:

generateExpression in class JavaValueNode

Parameters:

acb - The ExpressionClassBuilder for the class being built

mb - the method the expression will go into

Throws:

StandardException - Thrown on error

See Also:

QueryTreeNode.generate(org.apache.derby.impl.sql.compile.ActivationClassBuilder, org.apache.derby.iapi.services.compiler.MethodBuilder)