org.apache.derby.iapi.types
Class SQLVarchar

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

public class SQLVarchar
extends SQLChar

SQLVarchar represents a VARCHAR value with UCS_BASIC collation. 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
_clobValue, arg_passer, CHAR_HEADER_GENERATOR, RETURN_SPACE_THRESHOLD, stream
 
Fields inherited from interface org.apache.derby.iapi.types.StringDataValue
BOTH, COLLATION_DERIVATION_EXPLICIT, COLLATION_DERIVATION_IMPLICIT, COLLATION_DERIVATION_NONE, COLLATION_TYPE_TERRITORY_BASED, COLLATION_TYPE_TERRITORY_BASED_IDENTICAL, COLLATION_TYPE_TERRITORY_BASED_PRIMARY, COLLATION_TYPE_TERRITORY_BASED_SECONDARY, COLLATION_TYPE_TERRITORY_BASED_TERTIARY, COLLATION_TYPE_UCS_BASIC, LEADING, TRAILING
 
Fields inherited from interface org.apache.derby.iapi.types.DataValueDescriptor
UNKNOWN_LOGICAL_LENGTH
 
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.sql.Clob val)
           
SQLVarchar(java.lang.String val)
           
 
Method Summary
 DataValueDescriptor cloneValue(boolean forceMaterialization)
          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
 StringDataValue getValue(java.text.RuleBasedCollator collatorForComparison)
          Gets either SQLChar/SQLVarchar/SQLLongvarchar/SQLClob(base classes) or CollatorSQLChar/CollatorSQLVarchar/CollatorSQLLongvarch/CollatorSQLClob (subclasses).
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
ansiTrim, charLength, cloneHolder, compare, compare, concatenate, copyState, equals, estimateMemoryUsage, getBoolean, getByte, getCharArray, getCollationKey, getCollatorForCollation, getDate, getDate, getDateFormat, getDateFormat, getDouble, getFloat, getInt, getLength, getLocaleFinder, getLong, getNewVarchar, getObject, getShort, getStream, getStreamHeaderGenerator, getStreamWithDescriptor, getString, getTime, getTime, getTimeFormat, getTimeFormat, getTimestamp, getTimestamp, getTimestampFormat, getTimestampFormat, getTraceString, greaterOrEquals, greaterThan, hashCode, hashCodeForCollation, hasNonBlankChars, isNull, lessOrEquals, lessThan, like, like, loadStream, locate, lower, notEquals, readExternal, readExternal, readExternalClobFromArray, readExternalFromArray, restoreToNull, returnStream, setBigDecimal, setFrom, setInto, setLocaleFinder, setObjectForCast, setStream, setStreamHeaderFormat, setValue, setValue, setValue, setValue, setValue, setValue, setValue, setValue, setValue, setValue, setValue, setValue, setValue, setValue, setValueFromResultSet, setWidth, stringCompare, stringCompare, stringCompare, substring, throwStreamingIOException, toString, typeToBigDecimal, upper, writeClobUTF, writeExternal
 
Methods inherited from class org.apache.derby.iapi.types.DataType
checkHostVariable, coalesce, compare, compare, compareTo, dataTypeConversion, equals, flip, genericSetObject, getBytes, getNationalString, getTypeName, hasStream, in, invalidFormat, isNotNull, isNullOp, outOfRange, recycle, setInto, setObject, setToNull, 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
checkHostVariable, coalesce, compare, compare, getBytes, hasStream, in, isNotNull, isNullOp, recycle, setInto, setToNull, setValue, setValue, setValue, setValue, setValue
 

Constructor Detail

SQLVarchar

public SQLVarchar()

SQLVarchar

public SQLVarchar(java.lang.String val)

SQLVarchar

public SQLVarchar(java.sql.Clob 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
Returns:
The SQL name of the datatype

cloneValue

public DataValueDescriptor cloneValue(boolean forceMaterialization)
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.

Even though the objects can be modified independently regardless of the value of forceMaterialization, both the clone and the original may be dependent on the store state if forceMaterialization is set to false. An example is if you need to access the value you just read using cloneValue after the current transaction has ended, or after the source result set has been closed.

Specified by:
cloneValue in interface DataValueDescriptor
Overrides:
cloneValue in class SQLChar
Parameters:
forceMaterialization - any streams representing the data value will be materialized if true, the data value will be kept as a stream if possible if false
Returns:
A clone of the DataValueDescriptor with the same initial value as this.
See Also:
DataValueDescriptor.cloneValue(boolean)

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()

getValue

public StringDataValue getValue(java.text.RuleBasedCollator collatorForComparison)
Description copied from interface: StringDataValue
Gets either SQLChar/SQLVarchar/SQLLongvarchar/SQLClob(base classes) or CollatorSQLChar/CollatorSQLVarchar/CollatorSQLLongvarch/CollatorSQLClob (subclasses). Whether this method returns the base class or the subclass depends on the value of the RuleBasedCollator. If RuleBasedCollator is null, then the object returned would be baseclass otherwise it would be subcalss.

Specified by:
getValue in interface StringDataValue
Overrides:
getValue in class SQLChar
See Also:
StringDataValue.getValue(RuleBasedCollator)

getTypeFormatId

public int getTypeFormatId()
Return my format identifier.

Specified by:
getTypeFormatId in interface TypedFormat
Overrides:
getTypeFormatId in class SQLChar
Returns:
The identifier. (A UUID stuffed in an array of 16 bytes).
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
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 class: DataType
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
Returns:
The precedence of this type.
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 Thu 2012-03-29 21:53:33+0000, from revision ???

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