net.sf.jasperreports.engine.query
Class JRSqlLessOrGreaterClause

java.lang.Object
  net.sf.jasperreports.engine.query.JRSqlLessOrGreaterClause

All Implemented Interfaces:

JRClauseFunction

public class JRSqlLessOrGreaterClause
extends Object
implements JRClauseFunction

Base LESS/GREATER clause function for SQL queries.

The first token in the $X{...} syntax is the function ID token. Possible values for the LESS | GREATER clause function ID token are:

• LESS - in this case the LESS THAN operator < will be applied.
• LESS] - in this case the LESS OR EQUAL operator <= will be applied.
• GREATER - in this case the GREATER THAN operator > will be applied.
• [GREATER - in this case the GREATER OR EQUAL operator >= will be applied.

Version:

$Id: JRSqlLessOrGreaterClause.java 5180 2012-03-29 13:23:12Z teodord $

Author:

sanda zaharia (shertage@users.sourceforge.net)

Field Summary

protected static String	CLAUSE_TRUISM
protected static String	OPERATOR_GREATER
protected static String	OPERATOR_GREATER_OR_EQUAL
protected static String	OPERATOR_LESS
protected static String	OPERATOR_LESS_OR_EQUAL
protected static int	POSITION_CLAUSE_ID
protected static int	POSITION_DB_COLUMN
protected static int	POSITION_PARAMETER
protected static JRSqlLessOrGreaterClause	singleton

Constructor Summary

JRSqlLessOrGreaterClause()

Method Summary

void	apply(JRClauseTokens clauseTokens, JRQueryClauseContext queryContext) Creates either a LESS or a GREATER SQL clause, depending on the clause ID.
protected void	handleLessOrGreaterOperator(StringBuffer sBuffer, String clauseId) Appends the appropriate inequality sign to the query string, depending on the clause ID value
static JRSqlLessOrGreaterClause	instance() Returns the singleton function instance.

Methods inherited from class java.lang.Object

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

Field Detail

POSITION_CLAUSE_ID

protected static final int POSITION_CLAUSE_ID

See Also:

Constant Field Values

POSITION_DB_COLUMN

protected static final int POSITION_DB_COLUMN

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Constant Field Values

POSITION_PARAMETER

protected static final int POSITION_PARAMETER

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Constant Field Values

OPERATOR_LESS

protected static final String OPERATOR_LESS

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Constant Field Values

OPERATOR_LESS_OR_EQUAL

protected static final String OPERATOR_LESS_OR_EQUAL

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Constant Field Values

OPERATOR_GREATER

protected static final String OPERATOR_GREATER

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Constant Field Values

OPERATOR_GREATER_OR_EQUAL

protected static final String OPERATOR_GREATER_OR_EQUAL

See Also:

Constant Field Values

CLAUSE_TRUISM

protected static final String CLAUSE_TRUISM

See Also:

Constant Field Values

singleton

protected static final JRSqlLessOrGreaterClause singleton

Constructor Detail

JRSqlLessOrGreaterClause

public JRSqlLessOrGreaterClause()

Method Detail

instance

public static JRSqlLessOrGreaterClause instance()

Returns the singleton function instance.

Returns:

the singleton function instance

apply

public void apply(JRClauseTokens clauseTokens,
                  JRQueryClauseContext queryContext)

Creates either a LESS or a GREATER SQL clause, depending on the clause ID.

The method expects two clause tokens (after the ID token):

• The first token is the SQL column (or column combination) to be used in the clause.
• The second token is the name of the report parameter that contains the value to compare to.

The method constructs one of the following clauses:

• column < ? if the clause ID is LESS
• column <= ? if the clause ID is LESS]
• column >= ? if the clause ID is GREATER
• column > ? if the clause ID is [GREATER

If the value to compare to is null, the method generates a SQL clause that will always evaluate to true (e.g. 0 = 0).

Specified by:

apply in interface JRClauseFunction

Parameters:

clauseTokens - the clause tokens

queryContext - the query context

handleLessOrGreaterOperator

protected void handleLessOrGreaterOperator(StringBuffer sBuffer,
                                           String clauseId)

Appends the appropriate inequality sign to the query string, depending on the clause ID value

Parameters:

sBuffer - the StringBuffer that contains the generated query

clauseId - the clause ID