org.apache.derby.impl.sql.compile

Class SQLToJavaValueNode

java.lang.Object

org.apache.derby.impl.sql.compile.QueryTreeNode

org.apache.derby.impl.sql.compile.JavaValueNode

org.apache.derby.impl.sql.compile.SQLToJavaValueNode

All Implemented Interfaces:

Node, Visitable

public class SQLToJavaValueNode
extends JavaValueNode

This node type converts a value in the SQL domain to a value in the Java domain.

Field Summary

Fields

Modifier and Type	Field and Description
(package private) LocalField	returnsNullOnNullState If set then this SQL value is being passed into a SQL function declared RETURNS NULL ON NULL input.
(package private) ValueNode	value

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

Constructor Summary

Constructors

Constructor and Description
SQLToJavaValueNode()

Method Summary

Modifier and Type	Method and Description
(package private) void	acceptChildren(Visitor v) Accept the visitor for all visitable children of this node.
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) Generate code to get the Java value out of a SQL value.
private void	generateJavaValue(ExpressionClassBuilder acb, MethodBuilder mbex) Generate code to cast the SQLValue to a Java value.
private void	generateReturnsNullOnNullCheck(MethodBuilder mb) Generate the code for the returns Null on Null input check..
private void	generateSQLValue(ExpressionClassBuilder acb, MethodBuilder mb) Generate the SQLvalue that this node wraps.
(package private) java.lang.Object	getConstantValueAsObject()
DataTypeDescriptor	getDataType() Override behavior in superclass.
java.lang.String	getJavaTypeName() Returns the name of the java class type that this node coerces to.
JSQLType	getJSQLType() Get the JSQLType that corresponds to this node.
protected int	getOrderableVariantType() Return the variant type for the underlying expression.
java.lang.String	getPrimitiveTypeName() Returns the name of the java primitive type that this node coerces to.
private java.lang.String	getSQLValueInterfaceName() Get the type name of the SQLValue we generate.
(package private) ValueNode	getSQLValueNode() Get the SQL ValueNode that is being converted to a JavaValueNode
void	init(java.lang.Object value) Constructor for a SQLToJavaValueNode
void	preprocess(int numTables, FromList outerFromList, SubqueryList outerSubqueryList, PredicateList outerPredicateList) Preprocess an expression tree.
void	printSubNodes(int depth) Prints the sub-nodes of this object.
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, getReceiverExpression, isPrimitiveType, mapToTypeID, markForCallStatement, markReturnValueDiscarded, mustCastToPrimitive, returnValueDiscarded, returnValueToSQLDomain, setCollationType, setJavaTypeName, valueReturnedToSQLDomain

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, init, init, init, isAtomic, isInstanceOf, isPrivilegeCollectionRequired, isSessionSchema, isSessionSchema, makeConstantAction, makeTableName, makeTableName, nodeHeader, orReliability, parseStatement, printLabel, 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

value

ValueNode value

returnsNullOnNullState

LocalField returnsNullOnNullState

If set then this SQL value is being passed into a SQL function declared RETURNS NULL ON NULL input. In this case this node performs NULL checking logic in addition simple translation from the SQL domain to the Java domain. Thus if this is set then this node can not be removed when it is paired with a JavaToSQLValueNode. This field is set at generate time of the enclosing StaticMethodCallNode.

Constructor Detail

SQLToJavaValueNode

public SQLToJavaValueNode()

Method Detail

init

public void init(java.lang.Object value)

Constructor for a SQLToJavaValueNode

Specified by:

init in interface Node

Overrides:

init in class QueryTreeNode

Parameters:

value - A ValueNode representing a SQL value to convert to the Java domain.

printSubNodes

public void printSubNodes(int depth)

Prints the sub-nodes of this object. See QueryTreeNode.java for how tree printing is supposed to work.

Overrides:

printSubNodes in class QueryTreeNode

Parameters:

depth - The depth of this node in the tree

getJavaTypeName

public java.lang.String getJavaTypeName()
                                 throws StandardException

Returns the name of the java class type that this node coerces to.

Overrides:

getJavaTypeName in class JavaValueNode

Returns:

name of java class type

Throws:

StandardException

getPrimitiveTypeName

public java.lang.String getPrimitiveTypeName()
                                      throws StandardException

Returns the name of the java primitive type that this node coerces to.

Overrides:

getPrimitiveTypeName in class JavaValueNode

Returns:

name of java primitive type

Throws:

StandardException - Thrown on error

getJSQLType

public JSQLType getJSQLType()
                     throws StandardException

Get the JSQLType that corresponds to this node. Could be a SQLTYPE, a Java primitive, or a Java class. Overrides method in JavaValueNode.

Overrides:

getJSQLType in class JavaValueNode

Returns:

the corresponding JSQLType

Throws:

StandardException

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:

this

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)

getDataType

public DataTypeDescriptor getDataType()
                               throws StandardException

Override behavior in superclass.

Overrides:

getDataType in class JavaValueNode

Throws:

StandardException

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()

categorize

public boolean categorize(JBitSet referencedTabs,
                          boolean simplePredsOnly)
                   throws StandardException

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.

Throws:

StandardException - Thrown on error

See Also:

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

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)

getOrderableVariantType

protected int getOrderableVariantType()
                               throws StandardException

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 expressions)

Overrides:

getOrderableVariantType in class JavaValueNode

Returns:

The variant type for the underlying expression.

Throws:

StandardException - thrown on error

generateExpression

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

Generate code to get the Java value out of a SQL value. Every SQL type has a corresponding Java type. The getObject() method on the SQL type gets the right Java type. The generated code will be: () ((DataValueDescriptor) .getObject()) where comes from the getCorrespondingJavaTypeName() method of the value's TypeId.

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

generateSQLValue

private void generateSQLValue(ExpressionClassBuilder acb,
                              MethodBuilder mb)
                       throws StandardException

Generate the SQLvalue that this node wraps.

Parameters:

acb - The ExpressionClassBuilder for the class being built

mb - The method the expression will go into

Throws:

StandardException - Thrown on error

generateJavaValue

private void generateJavaValue(ExpressionClassBuilder acb,
                               MethodBuilder mbex)
                        throws StandardException

Generate code to cast the SQLValue to a Java value.

Parameters:

acb - The ExpressionClassBuilder for the class being built

mbex - The method the expression will go into

Throws:

StandardException - Thrown on error

generateReturnsNullOnNullCheck

private void generateReturnsNullOnNullCheck(MethodBuilder mb)

Generate the code for the returns Null on Null input check.. Stack must contain the DataDescriptorValue.

getSQLValueInterfaceName

private java.lang.String getSQLValueInterfaceName()
                                           throws StandardException

Get the type name of the SQLValue we generate.

Returns:

name of interface corresponding to SQLValue

Throws:

StandardException - Thrown on error

getSQLValueNode

ValueNode getSQLValueNode()

Get the SQL ValueNode that is being converted to a JavaValueNode

Returns:

The underlying SQL ValueNode

getConstantValueAsObject

java.lang.Object getConstantValueAsObject()
                                   throws StandardException

Overrides:

getConstantValueAsObject in class JavaValueNode

Throws:

StandardException - Thrown on error

See Also:

ValueNode.getConstantValueAsObject()

acceptChildren

void acceptChildren(Visitor v)
             throws StandardException

Accept the visitor for all visitable children of this node.

Overrides:

acceptChildren in class QueryTreeNode

Parameters:

v - the visitor

Throws:

StandardException - on error