Package org.sqlproc.engine.impl

Class SqlMetaIf

java.lang.Object

org.sqlproc.engine.impl.SqlMetaIf

All Implemented Interfaces:

SqlMetaElement

class SqlMetaIf
extends Object
implements SqlMetaElement

A META SQL sub-element.

Schematically:

 SqlMetaIf 
     {? SqlMetaLogExpr | SqlMetaIfItem | SqlMetaIfItem...}
 

Author:

Vladimir Hudec

Field Summary

Fields

Modifier and Type	Field	Description
(package private) List<SqlMetaIfItem>	elements	The list of maximum 2 sub-elements based on ANTLR grammar.
(package private) SqlMetaLogExpr	expression	The logical expression.
(package private) final org.slf4j.Logger	logger	The internal slf4j logger.

Fields inherited from interface org.sqlproc.engine.impl.SqlMetaElement

AND_PREFIX, CONST_PREFIX, IDENT_PREFIX, IDENT_SEPARATOR, lCONST_PREFIX, lIDENT_PREFIX, OR_PREFIX, SET_PREFIX, VALUES_PREFIX, WHERE_PREFIX

Constructor Summary

Constructors

Constructor	Description
SqlMetaIf()	Creates a new instance.

Method Summary

Modifier and Type	Method	Description
(package private) void	addElement(SqlMetaIfItem element)	Adds a new sub-element.
SqlProcessResult	process(SqlProcessContext ctx)	The main contract for a dynamic ANSI SQL Query generation.
(package private) void	setExpression(SqlMetaLogExpr expression)	Sets a logical expression.

Methods inherited from class java.lang.Object

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

Field Details

logger

final org.slf4j.Logger logger

The internal slf4j logger.

elements

List<SqlMetaIfItem> elements

The list of maximum 2 sub-elements based on ANTLR grammar.

expression

SqlMetaLogExpr expression

The logical expression. Based on the value of this expression the first or the second sub-element will become a part of the final ANSI SQL.

Constructor Details

SqlMetaIf

SqlMetaIf()

Creates a new instance. It's used from inside ANTLR parser.

Method Details

addElement

void addElement(SqlMetaIfItem element)

Adds a new sub-element. It's used from inside ANTLR parser.

Parameters:

element - new sub-element, based on ANTLR grammar

setExpression

void setExpression(SqlMetaLogExpr expression)

Sets a logical expression. It's used from inside ANTLR parser. Based on the value of this expression the first or the second sub-element will become a part of the final ANSI SQL.

Parameters:

expression - the new value of logical expression

process

public SqlProcessResult process(SqlProcessContext ctx)

The main contract for a dynamic ANSI SQL Query generation. Also known as a META SQL processing. The composite pattern main contract. All ANTLR grammar based elements must implement this contract.

Specified by:

process in interface SqlMetaElement

Parameters:

ctx - the crate for all input parameters and the context of processing