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

java.lang.Object
  org.apache.derby.impl.sql.compile.QueryTreeNode
      org.apache.derby.impl.sql.compile.ValueNode
          org.apache.derby.impl.sql.compile.OperatorNode
              org.apache.derby.impl.sql.compile.BinaryOperatorNode
                  org.apache.derby.impl.sql.compile.BinaryLogicalOperatorNode
                      org.apache.derby.impl.sql.compile.IsNode

All Implemented Interfaces:

Node, Visitable

public class IsNode
extends BinaryLogicalOperatorNode

Field Summary

private boolean

notMe

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

shortCircuitValue

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

AND, BinaryArgTypes, BinaryMethodNames, BinaryOperators, BinaryResultTypes, CONCATENATE, DIVIDE, EQ, GE, GT, LE, leftInterfaceType, leftOperand, LIKE, LT, methodName, MINUS, NE, operator, operatorType, OR, PLUS, receiver, resultInterfaceType, rightInterfaceType, rightOperand, TIMES, XMLEXISTS_OP, XMLQUERY_OP

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

transformed

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

IsNode()

Method Summary

ValueNode	bindExpression(FromList fromList, SubqueryList subqueryList, java.util.List aggregateVector) Bind this logical operator.
ValueNode	changeToCNF(boolean underTopAndNode) Finish putting an expression into conjunctive normal form.
(package private) ValueNode	eliminateNots(boolean underNotNode) Eliminate NotNodes in the current query block.
void	generateExpression(ExpressionClassBuilder acb, MethodBuilder mb) Do code generation for this logical binary operator.
void	init(java.lang.Object leftOperand, java.lang.Object rightOperand, java.lang.Object notMe) Initializer for an IsNode
ValueNode	putAndsOnTop() Do the 1st step in putting child expressions into conjunctive normal form.
boolean	verifyChangeToCNF() Verify that changeToCNF() did its job correctly.
boolean	verifyPutAndsOnTop() Verify that putAndsOnTop() did its job correctly.

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

resolveLogicalBinaryOperator, verifyEliminateNots

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

acceptChildren, bindXMLQuery, categorize, constantExpression, genSQLJavaSQLTree, getLeftOperand, getOrderableVariantType, getReceiverInterfaceName, getRightOperand, init, init, isConstantExpression, isEquivalent, preprocess, printSubNodes, remapColumnReferencesToExpressions, setLeftOperand, setLeftRightInterfaceType, setMethodName, setOperator, setRightOperand, toString

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

pushSqlXmlUtil

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

bindExpression, checkIsBoolean, checkTopPredicatesForEqualsConditions, copyFields, evaluateConstantExpressions, genEqualsFalseTree, generate, generateFilter, genIsNullTree, getClone, getColumnName, getConstantValueAsObject, getDataValueFactory, getSchemaName, getSourceResultColumn, getTableName, getTablesReferenced, getTransformed, getTypeCompiler, getTypeId, getTypeServices, init, isBinaryEqualsOperatorNode, isBooleanFalse, isBooleanTrue, isCloneable, isInListProbeNode, isParameterNode, isRelationalOperator, isSameNodeType, optimizableEqualityNode, requiresTypeFromContext, selectivity, setCollationInfo, setCollationInfo, setCollationUsingCompilationSchema, setCollationUsingCompilationSchema, setNullability, setTransformed, setType, setType, setType, updatableByCursor

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

accept, 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, isAtomic, isInstanceOf, isPrivilegeCollectionRequired, isSessionSchema, isSessionSchema, makeConstantAction, makeTableName, makeTableName, nodeHeader, orReliability, parseStatement, printLabel, referencesSessionSchema, resolveTableToSynonym, setBeginOffset, setContextManager, setEndOffset, setNodeType, setRefActionInfo, stackPrint, treePrint, treePrint, verifyClassExist

Methods inherited from class java.lang.Object

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

Field Detail

notMe

private boolean notMe

Constructor Detail

IsNode

public IsNode()

Method Detail

init

public void init(java.lang.Object leftOperand,
                 java.lang.Object rightOperand,
                 java.lang.Object notMe)

Initializer for an IsNode

Specified by:

init in interface Node

Overrides:

init in class BinaryLogicalOperatorNode

Parameters:

leftOperand - The left operand of the IS

rightOperand - The right operand of the IS

notMe - Whether to reverse the sense of this node.

bindExpression

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

Bind this logical operator. All that has to be done for binding a logical operator is to bind the operands, check that both operands are BooleanDataValue, and set the result type to BooleanDataValue.

Overrides:

bindExpression in class BinaryLogicalOperatorNode

Parameters:

fromList - The query's FROM list

subqueryList - The subquery list being built as we find SubqueryNodes

aggregateVector - The aggregate vector being built as we find AggregateNodes

Returns:

The new top of the expression tree.

Throws:

StandardException - Thrown on error

eliminateNots

ValueNode eliminateNots(boolean underNotNode)
                  throws StandardException

Eliminate NotNodes in the current query block. We just mark whether this IS node is under an eliminated NOT node.

Overrides:

eliminateNots in class ValueNode

Parameters:

underNotNode - Whether or not we are under a NotNode.

Returns:

The modified expression

Throws:

StandardException - Thrown on error

putAndsOnTop

public ValueNode putAndsOnTop()
                       throws StandardException

Do the 1st step in putting child expressions into conjunctive normal form. This step ensures that the top level of the child expression is a chain of AndNodes terminated by a true BooleanConstantNode.

Overrides:

putAndsOnTop in class ValueNode

Returns:

The modified expression

Throws:

StandardException - Thrown on error

verifyPutAndsOnTop

public boolean verifyPutAndsOnTop()

Verify that putAndsOnTop() did its job correctly. Verify that the top level of the expression is a chain of AndNodes terminated by a true BooleanConstantNode.

Overrides:

verifyPutAndsOnTop in class ValueNode

Returns:

Boolean which reflects validity of the tree.

changeToCNF

public ValueNode changeToCNF(boolean underTopAndNode)
                      throws StandardException

Finish putting an expression into conjunctive normal form. An expression tree in conjunctive normal form meets the following criteria: o If the expression tree is not null, the top level will be a chain of AndNodes terminating in a true BooleanConstantNode. o The left child of an AndNode will never be an AndNode. o Any right-linked chain that includes an AndNode will be entirely composed of AndNodes terminated by a true BooleanConstantNode. o The left child of an OrNode will never be an OrNode. o Any right-linked chain that includes an OrNode will be entirely composed of OrNodes terminated by a false BooleanConstantNode. o ValueNodes other than AndNodes and OrNodes are considered leaf nodes for purposes of expression normalization. In other words, we won't do any normalization under those nodes. In addition, we track whether or not we are under a top level AndNode. SubqueryNodes need to know this for subquery flattening.

Overrides:

changeToCNF in class ValueNode

Parameters:

underTopAndNode - Whether or not we are under a top level AndNode.

Returns:

The modified expression

Throws:

StandardException - Thrown on error

verifyChangeToCNF

public boolean verifyChangeToCNF()

Verify that changeToCNF() did its job correctly. Verify that: o AndNode - rightOperand is not instanceof OrNode leftOperand is not instanceof AndNode o OrNode - rightOperand is not instanceof AndNode leftOperand is not instanceof OrNode

Overrides:

verifyChangeToCNF in class ValueNode

Returns:

Boolean which reflects validity of the tree.

generateExpression

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

Do code generation for this logical binary operator.

Overrides:

generateExpression in class BinaryLogicalOperatorNode

Parameters:

acb - The ExpressionClassBuilder for the class we're generating

mb - the method the expression will go into

Throws:

StandardException - Thrown on error