org.apache.empire.db.expr.compare
Class DBCompareColExpr

java.lang.Object
  extended by org.apache.empire.commons.ErrorObject
      extended by org.apache.empire.db.DBObject
          extended by org.apache.empire.db.DBExpr
              extended by org.apache.empire.db.expr.compare.DBCompareExpr
                  extended by org.apache.empire.db.expr.compare.DBCompareColExpr
All Implemented Interfaces:
ErrorInfo

public class DBCompareColExpr
extends DBCompareExpr

This class is used for defining filter constraints based on a column expression in SQL

There is no need to explicitly create instances of this class.
Instead use any of the following functions:
DBColumnExpr.is(Object), DBColumnExpr.isBetween(Object, Object), DBColumnExpr.isGreaterThan(Object), DBColumnExpr.isLessOrEqual(Object), DBColumnExpr.isMoreOrEqual(Object), DBColumnExpr.isNot(Object), DBColumnExpr.isNotBetween(Object, Object), DBColumnExpr.isSmallerThan(Object), DBColumnExpr.like(Object), DBColumnExpr.like(String, char), DBColumnExpr.likeLower(String), DBColumnExpr.likeUpper(String)


Field Summary
 
Fields inherited from class org.apache.empire.db.DBExpr
CTX_ALIAS, CTX_ALL, CTX_DEFAULT, CTX_FULLNAME, CTX_NAME, CTX_NOPARENTHESES, CTX_VALUE
 
Constructor Summary
DBCompareColExpr(DBColumnExpr expr, DBCmpType op, java.lang.Object value)
          Constructs a DBCompareColExpr object set the specified parameters to this object.
 
Method Summary
 void addCompareExpr(java.lang.StringBuilder buf, long context)
          Add the comparison operator and value to the SQL-Command.
 void addReferencedColumns(java.util.Set<DBColumn> list)
          Internal function to obtain all DBColumnExpr-objects used by this expression.
 void addSQL(java.lang.StringBuilder buf, long context)
          Creates the SQL-Command.
 DBCmpType getCmpop()
           
 DBColumnExpr getColumnExpr()
          returns the DBColumnExpr object
 DBDatabase getDatabase()
          Returns the current DBDatabase object.
 java.lang.Object getValue()
           
 boolean isMutuallyExclusive(DBCompareExpr other)
          Returns wheter the constraint should replace another one or not.
 void setValue(java.lang.Object value)
          The value to compare the column expression with
 
Methods inherited from class org.apache.empire.db.expr.compare.DBCompareExpr
and, not, or
 
Methods inherited from class org.apache.empire.db.DBExpr
getValueClass
 
Methods inherited from class org.apache.empire.commons.ErrorObject
clearError, getErrorMessage, getErrorParams, getErrorSource, getErrorType, getMessage, hasError, isExceptionsEnabled, setExceptionsEnabled
 
Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

DBCompareColExpr

public DBCompareColExpr(DBColumnExpr expr,
                        DBCmpType op,
                        java.lang.Object value)
Constructs a DBCompareColExpr object set the specified parameters to this object.

Parameters:
expr - the DBColumnExpr object
op - the comparative context e.g. (CMP_EQUAL, CMP_SMALLER)
value - the comparative value
Method Detail

getDatabase

public DBDatabase getDatabase()
Returns the current DBDatabase object.

Specified by:
getDatabase in class DBObject
Returns:
the current DBDatabase object

getColumnExpr

public DBColumnExpr getColumnExpr()
returns the DBColumnExpr object


getCmpop

public DBCmpType getCmpop()
Returns:
the comparison operator

getValue

public java.lang.Object getValue()
Returns:
the value to compare the column expression with

setValue

public void setValue(java.lang.Object value)
The value to compare the column expression with

Parameters:
value - the comparision value

addReferencedColumns

public void addReferencedColumns(java.util.Set<DBColumn> list)
Description copied from class: DBExpr
Internal function to obtain all DBColumnExpr-objects used by this expression.

Specified by:
addReferencedColumns in class DBExpr
Parameters:
list - list to which all used column expressions must be added
See Also:
DBExpr.addReferencedColumns(Set)

addCompareExpr

public void addCompareExpr(java.lang.StringBuilder buf,
                           long context)
Add the comparison operator and value to the SQL-Command.

Parameters:
buf - the SQL-Command
context - the comparative context e.g. (CMP_EQUAL, CMP_SMALLER)

addSQL

public void addSQL(java.lang.StringBuilder buf,
                   long context)
Creates the SQL-Command.

Specified by:
addSQL in class DBExpr
Parameters:
buf - the SQL-Command
context - the current SQL-Command context

isMutuallyExclusive

public boolean isMutuallyExclusive(DBCompareExpr other)
Returns wheter the constraint should replace another one or not.

Specified by:
isMutuallyExclusive in class DBCompareExpr
Returns:
true it the constraints are mutually exclusive or false otherwise