javatools.db
Class DbAndExpr

java.lang.Object
  |
  +--javatools.db.DbExpr
        |
        +--javatools.db.DbCriterion
              |
              +--javatools.db.DbAndExpr

All Implemented Interfaces:

DbTableUser

public class DbAndExpr

extends DbCriterion

An expression of the form A AND B. The reason we have this class as well as DbCriterion, is that this class will optimise away unnecessary segments. i.e. A AND TRUE will be optimised to just A. The reason you may find a TRUE expression in your code is the use of DbDatabase.trueExpr(). Of course we could just leave the dummy true expressions in the final SQL and presumably the dbms can optimise it away fine, but it looks a bit ugly and nasty to have these dummy expressions in the result.

See Also:

DbTrueExpr

Constructor Summary

DbAndExpr(DbDatabase db, java.lang.Object o1, java.lang.Object o2)
Builds a new "and" expression in the form "o1 AND o2".

Method Summary

java.lang.String	getQueryString() Returns the query string related to this expression.
int	setSqlValues(java.sql.PreparedStatement ps, int i) Obscure...

Methods inherited from class javatools.db.DbCriterion

usesTables

Methods inherited from class javatools.db.DbExpr

and, containsAllStrings, containsAllStrings, count, dateTrunc, equal, greaterThan, greaterThanOrEqual, in, in, isNotNull, isNull, lessThan, lessThanOrEqual, like, lower, max, min, notEqual, notIn, notIn, or, upper, usesTables

Methods inherited from class java.lang.Object

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

Constructor Detail

DbAndExpr

public DbAndExpr(DbDatabase db,
                 java.lang.Object o1,
                 java.lang.Object o2)

Builds a new "and" expression in the form "o1 AND o2".

Parameters:

db - The database used to build this expression.

o1 - The first term.

o2 - The second term.

Method Detail

getQueryString

public java.lang.String getQueryString()
                                throws DbException

Returns the query string related to this expression.

Overrides:

getQueryString in class DbCriterion

Returns:

The needed string.

Throws:

DbException - If something goes wrong.

setSqlValues

public int setSqlValues(java.sql.PreparedStatement ps,
                        int i)
                 throws java.sql.SQLException,
                        DbException

Obscure... Talk to Chris.

Overrides:

setSqlValues in class DbCriterion

Parameters:

ps - The prepared statement.

i - The index.

Returns:

The return value

Throws:

java.sql.SQLException - If something goes wrong.

DbException - If something goes wrong.