org.apache.derby.iapi.types
Class SQLVarbit

java.lang.Object
  extended byorg.apache.derby.iapi.types.DataType
      extended byorg.apache.derby.iapi.types.SQLBinary
          extended byorg.apache.derby.iapi.types.SQLBit
              extended byorg.apache.derby.iapi.types.SQLVarbit
All Implemented Interfaces:
BitDataValue, CloneableObject, ConcatableDataValue, DataValueDescriptor, java.io.Externalizable, Formatable, Orderable, java.io.Serializable, Storable, StreamStorable, TypedFormat, VariableSizeDataValue
Direct Known Subclasses:
SQLLongVarbit

public class SQLVarbit
extends SQLBit

SQLVarbit satisfies the DataValueDescriptor interfaces (i.e., OrderableDataType). It implements a String holder, e.g. for storing a column value; it can be specified when constructed to not allow nulls. Nullability cannot be changed after construction.

Because OrderableDataType is a subclass of DataType, SQLVarbit can play a role in either a DataType/Value or a OrderableDataType/KeyRow, interchangeably. It is an extension of SQLVarbit and is virtually indistinguishable other than normalization.

See Also:
Serialized Form

Field Summary
 
Fields inherited from class org.apache.derby.iapi.types.SQLBinary
dataValue, PAD, stream, streamLength
 
Fields inherited from interface org.apache.derby.iapi.types.Orderable
ORDER_OP_EQUALS, ORDER_OP_GREATEROREQUALS, ORDER_OP_GREATERTHAN, ORDER_OP_LESSOREQUALS, ORDER_OP_LESSTHAN
 
Fields inherited from interface org.apache.derby.iapi.types.VariableSizeDataValue
IGNORE_PRECISION
 
Constructor Summary
SQLVarbit()
           
SQLVarbit(byte[] val)
           
 
Method Summary
 DataValueDescriptor getNewNull()
          Get a new null value of the same type as this data value.
 int getTypeFormatId()
          Return my format identifier.
 java.lang.String getTypeName()
          Get the SQL name of the datatype
 void normalize(DataTypeDescriptor desiredType, DataValueDescriptor source)
          Normalization method - this method may be called when putting a value into a SQLBit, for example, when inserting into a SQLBit column.
 DataValueDescriptor setWidth(int desiredWidth, int desiredScale, boolean errorOnTrunc)
          Set the width of the to the desired value.
 int typePrecedence()
          Each built-in type in JSQL has a precedence.
 
Methods inherited from class org.apache.derby.iapi.types.SQLBit
getObject, setValue, setValueFromResultSet
 
Methods inherited from class org.apache.derby.iapi.types.SQLBinary
charLength, checkHostVariable, cloneObject, compare, compare, concatenate, equals, estimateMemoryUsage, getBytes, getClone, getLength, getStream, getString, getValue, greaterOrEquals, greaterThan, hashCode, isNull, lessOrEquals, lessThan, loadStream, notEquals, objectNull, readExternal, readExternalFromArray, restoreToNull, returnStream, setFrom, setStream, setValue, setValue, substring, toString, writeExternal
 
Methods inherited from class org.apache.derby.iapi.types.DataType
coalesce, dataTypeConversion, equals, flip, genericSetObject, getBigDecimal, getBoolean, getByte, getDate, getDouble, getFloat, getInt, getLong, getNationalString, getShort, getTime, getTimestamp, in, invalidFormat, isNotNull, isNullOp, outOfRange, setInto, setInto, setObjectForCast, setToNull, setValue, setValue, setValue, setValue, setValue, setValue, setValue, setValue, setValue, setValue, setValue, setValue, setValue, setValue, setValue, setValue, throwLangSetMismatch, throwLangSetMismatch
 
Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait
 
Methods inherited from interface org.apache.derby.iapi.types.DataValueDescriptor
coalesce, getBigDecimal, getBoolean, getByte, getDate, getDouble, getFloat, getInt, getLong, getShort, getTime, getTimestamp, in, isNotNull, isNullOp, setInto, setInto, setObjectForCast, setToNull, setValue, setValue, setValue, setValue, setValue, setValue, setValue, setValue, setValue, setValue, setValue, setValue, setValue, setValue, setValue, setValue
 

Constructor Detail

SQLVarbit

public SQLVarbit()

SQLVarbit

public SQLVarbit(byte[] val)
Method Detail

getTypeName

public java.lang.String getTypeName()
Description copied from interface: DataValueDescriptor
Get the SQL name of the datatype

Specified by:
getTypeName in interface DataValueDescriptor
Overrides:
getTypeName in class SQLBit

getNewNull

public DataValueDescriptor getNewNull()
Description copied from interface: DataValueDescriptor
Get a new null value of the same type as this data value.

Specified by:
getNewNull in interface DataValueDescriptor
Overrides:
getNewNull in class SQLBit
See Also:
DataValueDescriptor.getNewNull()

getTypeFormatId

public int getTypeFormatId()
Return my format identifier.

Specified by:
getTypeFormatId in interface TypedFormat
Overrides:
getTypeFormatId in class SQLBit
See Also:
TypedFormat.getTypeFormatId()

normalize

public void normalize(DataTypeDescriptor desiredType,
                      DataValueDescriptor source)
               throws StandardException
Normalization method - this method may be called when putting a value into a SQLBit, for example, when inserting into a SQLBit column. See NormalizeResultSet in execution.

Specified by:
normalize in interface DataValueDescriptor
Overrides:
normalize in class SQLBit
Parameters:
desiredType - The type to normalize the source column to
source - The value to normalize
Throws:
StandardException - Thrown for null into non-nullable column, and for truncation error

setWidth

public DataValueDescriptor setWidth(int desiredWidth,
                                    int desiredScale,
                                    boolean errorOnTrunc)
                             throws StandardException
Set the width of the to the desired value. Used when CASTing. Ideally we'd recycle normalize(), but the behavior is different (we issue a warning instead of an error, and we aren't interested in nullability).

Specified by:
setWidth in interface VariableSizeDataValue
Overrides:
setWidth in class SQLBit
Parameters:
desiredWidth - the desired length
desiredScale - the desired scale (ignored)
errorOnTrunc - throw error on truncation
Returns:
this with the target width
Throws:
StandardException - Thrown on non-zero truncation if errorOnTrunc is true

typePrecedence

public int typePrecedence()
Description copied from interface: DataValueDescriptor
Each built-in type in JSQL has a precedence. This precedence determines how to do type promotion when using binary operators. For example, float has a higher precedence than int, so when adding an int to a float, the result type is float. The precedence for some types is arbitrary. For example, it doesn't matter what the precedence of the boolean type is, since it can't be mixed with other types. But the precedence for the number types is critical. The SQL standard requires that exact numeric types be promoted to approximate numeric when one operator uses both. Also, the precedence is arranged so that one will not lose precision when promoting a type.

Specified by:
typePrecedence in interface DataValueDescriptor
Overrides:
typePrecedence in class SQLBit
See Also:
DataValueDescriptor.typePrecedence()


Apache Derby V10.0 Engine Documentation - Copyright © 1997,2004 The Apache Software Foundation or its licensors, as applicable.