org.apache.derby.iapi.types
Class SQLVarchar

java.lang.Object
  extended byorg.apache.derby.iapi.types.DataType
      extended byorg.apache.derby.iapi.types.SQLChar
          extended byorg.apache.derby.iapi.types.SQLVarchar
All Implemented Interfaces:
CloneableObject, ConcatableDataValue, DataValueDescriptor, java.io.Externalizable, Formatable, Orderable, java.io.Serializable, Storable, StreamStorable, StringDataValue, TypedFormat, VariableSizeDataValue
Direct Known Subclasses:
SQLClob, SQLLongvarchar, SQLNationalVarchar

public class SQLVarchar
extends SQLChar

SQLVarchar 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, SQLVarchar can play a role in either a DataType/ValueRow or a OrderableDataType/KeyRow, interchangeably. SQLVarchar is mostly the same as SQLChar, so it is implemented as a subclass of SQLChar. Only those methods with different behavior are implemented here.

See Also:
Serialized Form

Field Summary
 
Fields inherited from class org.apache.derby.iapi.types.SQLChar
arg_passer, RETURN_SPACE_THRESHOLD, stream
 
Fields inherited from interface org.apache.derby.iapi.types.StringDataValue
BOTH, LEADING, TRAILING
 
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
SQLVarchar()
           
SQLVarchar(java.lang.String val)
           
 
Method Summary
 DataValueDescriptor getClone()
          Clone this DataValueDescriptor.
 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
protected  int growBy()
          returns the reasonable minimum amount by which the array can grow .
 void normalize(DataTypeDescriptor desiredType, DataValueDescriptor source)
          Normalization method - this method may be called when putting a value into a SQLVarchar, for example, when inserting into a SQLVarchar column.
protected  void normalize(DataTypeDescriptor desiredType, java.lang.String sourceValue)
           
 int typePrecedence()
          Each built-in type in JSQL has a precedence.
 
Methods inherited from class org.apache.derby.iapi.types.SQLChar
appendBlanks, charLength, cloneObject, compare, compare, concatenate, copyState, equals, estimateMemoryUsage, getBoolean, getByte, getCharArray, getCollationKey, getDate, getDate, getDateFormat, getDateFormat, getDouble, getFloat, getInt, getLength, getLocaleFinder, getLong, getNewVarchar, getObject, getShort, getStream, getString, getTime, getTime, getTimeFormat, getTimeFormat, getTimestamp, getTimestamp, getTimestampFormat, getTimestampFormat, greaterOrEquals, greaterThan, hashCode, hasNonBlankChars, isNationalString, isNull, lessOrEquals, lessThan, like, like, loadStream, locate, lower, nationalGetDate, nationalGetTime, nationalGetTimestamp, nationalHashCode, notEquals, readExternal, readExternalFromArray, restoreToNull, returnStream, setBigDecimal, setFrom, setInto, setLocaleFinder, setStream, setValue, setValue, setValue, setValue, setValue, setValue, setValue, setValue, setValue, setValue, setValue, setValue, setValue, setValue, setValueFromResultSet, setWidth, stringCollatorCompare, stringCompare, stringCompare, stringCompare, substring, toString, trim, typeToBigDecimal, upper, writeExternal, XMLParse
 
Methods inherited from class org.apache.derby.iapi.types.DataType
checkHostVariable, coalesce, dataTypeConversion, equals, flip, genericSetObject, getBytes, getNationalString, in, invalidFormat, isNotNull, isNullOp, outOfRange, setInto, setObjectForCast, setToNull, 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
checkHostVariable, coalesce, getBytes, in, isNotNull, isNullOp, setInto, setObjectForCast, setToNull, setValue, setValue, setValue, setValue
 

Constructor Detail

SQLVarchar

public SQLVarchar()

SQLVarchar

public SQLVarchar(java.lang.String 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 SQLChar

getClone

public DataValueDescriptor getClone()
Description copied from interface: DataValueDescriptor
Clone this DataValueDescriptor. Results in a new object that has the same value as this but can be modified independently.

Specified by:
getClone in interface DataValueDescriptor
Overrides:
getClone in class SQLChar
See Also:
DataValueDescriptor.getClone()

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 SQLChar
See Also:
DataValueDescriptor.getNewNull()

getTypeFormatId

public int getTypeFormatId()
Return my format identifier.

Specified by:
getTypeFormatId in interface TypedFormat
Overrides:
getTypeFormatId in class SQLChar
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 SQLVarchar, for example, when inserting into a SQLVarchar column. See NormalizeResultSet in execution.

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

normalize

protected void normalize(DataTypeDescriptor desiredType,
                         java.lang.String sourceValue)
                  throws StandardException
Overrides:
normalize in class SQLChar
Throws:
StandardException

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 SQLChar
See Also:
DataValueDescriptor.typePrecedence()

growBy

protected final int growBy()
returns the reasonable minimum amount by which the array can grow . See readExternal. when we know that the array needs to grow by at least one byte, it is not performant to grow by just one byte instead this amount is used to provide a resonable growby size.

Overrides:
growBy in class SQLChar
Returns:
minimum reasonable growby size

Built on Mon 2007-06-04 09:58:47+0400, from revision ???

Apache Derby V10.1 Engine Documentation - Copyright © 1997,2005 The Apache Software Foundation or its licensors, as applicable.