org.apache.derby.iapi.types

Class SQLBoolean

java.lang.Object

org.apache.derby.iapi.types.DataType

org.apache.derby.iapi.types.SQLBoolean

All Implemented Interfaces:

java.io.Externalizable, java.io.Serializable, java.lang.Comparable, Formatable, Storable, TypedFormat, BooleanDataValue, DataValueDescriptor, Orderable

public final class SQLBoolean
extends DataType
implements BooleanDataValue

SQLBoolean satisfies the DataValueDescriptor interfaces (i.e., DataType). It implements a boolean column, e.g. for * storing a column value; it can be specified when constructed to not allow nulls. Nullability cannot be changed after construction, as it affects the storage size and mechanism.

Because DataType is a subtype of DataType, SQLBoolean can play a role in either a DataType/Row or a DataType/Row, interchangeably.

We assume the store has a flag for nullness of the value, and simply return a 0-length array for the stored form when the value is null.

PERFORMANCE: There are likely alot of performance improvements possible for this implementation -- it new's Integer more than it probably wants to.

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
private static int	BASE_MEMORY_USAGE
private static SQLBoolean	BOOLEAN_FALSE
(package private) static int	BOOLEAN_LENGTH
private static SQLBoolean	BOOLEAN_TRUE
private boolean	immutable
private boolean	isnull
(package private) static SQLBoolean	UNKNOWN
private boolean	value

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

Constructor Summary

Constructors

Modifier	Constructor and Description
	SQLBoolean()
	SQLBoolean(boolean val)
	SQLBoolean(java.lang.Boolean obj)
private	SQLBoolean(boolean val, boolean isnull)

Method Summary

Modifier and Type	Method and Description
BooleanDataValue	and(BooleanDataValue otherValue) The AND operator.
DataValueDescriptor	cloneValue(boolean forceMaterialization) Clone this DataValueDescriptor.
int	compare(DataValueDescriptor other) Compare this Orderable with a given Orderable for the purpose of index positioning.
boolean	compare(int op, DataValueDescriptor other, boolean orderedNulls, boolean unknownRV) Compare this Orderable with a given Orderable for the purpose of qualification and sorting.
boolean	equals(boolean val) Determine whether this SQLBoolean contains the given boolean value.
BooleanDataValue	equals(DataValueDescriptor left, DataValueDescriptor right) The = operator as called from the language module, as opposed to the storage module.
int	estimateMemoryUsage() Estimate the memory usage in bytes of the data value and the overhead of the class.
boolean	getBoolean() Gets the value in the data value descriptor as a boolean.
byte	getByte() Gets the value in the data value descriptor as a byte.
double	getDouble() Gets the value in the data value descriptor as a double.
float	getFloat() Gets the value in the data value descriptor as a float.
BooleanDataValue	getImmutable() Return an immutable BooleanDataValue with the same value as this.
int	getInt() Gets the value in the data value descriptor as a int.
int	getLength() Gets the length of the data value.
long	getLong() Gets the value in the data value descriptor as a long.
DataValueDescriptor	getNewNull() Get a new null value of the same type as this data value.
java.lang.Object	getObject() Gets the value in the data value descriptor as a int.
short	getShort() Gets the value in the data value descriptor as a short.
java.lang.String	getString() Gets the value in the data value descriptor as a String.
int	getTypeFormatId() Return my format identifier.
java.lang.String	getTypeName() Get the SQL name of the datatype
BooleanDataValue	greaterOrEquals(DataValueDescriptor left, DataValueDescriptor right) The >= operator as called from the language module, as opposed to the storage module.
BooleanDataValue	greaterThan(DataValueDescriptor left, DataValueDescriptor right) The > operator as called from the language module, as opposed to the storage module.
int	hashCode()
BooleanDataValue	is(BooleanDataValue otherValue) The SQL IS operator - consult any standard SQL reference for an explanation.
BooleanDataValue	isNot(BooleanDataValue otherValue) Implements NOT IS.
boolean	isNull() Return whether the value is null or not.
BooleanDataValue	lessOrEquals(DataValueDescriptor left, DataValueDescriptor right) The <= operator as called from the language module, as opposed to the storage module.
BooleanDataValue	lessThan(DataValueDescriptor left, DataValueDescriptor right) The < operator as called from the language module, as opposed to the storage module.
private static int	makeInt(boolean b)
BooleanDataValue	notEquals(DataValueDescriptor left, DataValueDescriptor right) The <> operator as called from the language module, as opposed to the storage module.
BooleanDataValue	or(BooleanDataValue otherValue) The OR operator.
void	readExternal(java.io.ObjectInput in)
DataValueDescriptor	recycle() Recycle this SQLBoolean object if possible.
void	restoreToNull() Restore this object to its (SQL)null value.
void	setBigDecimal(java.lang.Number bigDecimal) Only to be called when the application sets a value using BigDecimal
protected void	setFrom(DataValueDescriptor theValue) Set the value of this DataValueDescriptor based on the value of the specified DataValueDescriptor.
void	setInto(java.sql.PreparedStatement ps, int position) Set the value into a PreparedStatement.
(package private) void	setObject(java.lang.Object theValue) Set the value from an non-null object.
void	setValue(boolean theValue) Set the value.
void	setValue(java.lang.Boolean theValue) Set the value of this BooleanDataValue.
void	setValue(byte theValue) Set the value of this DataValueDescriptor to the given byte value At DataType level just throws an error lower classes will override
void	setValue(double theValue) Set the value of this DataValueDescriptor to the given double value At DataType level just throws an error lower classes will override
void	setValue(float theValue) Set the value of this DataValueDescriptor to the given float value At DataType level just throws an error lower classes will override
void	setValue(int theValue) Set the value of this DataValueDescriptor to the given int value At DataType level just throws an error lower classes will override
void	setValue(long theValue) Set the value of this DataValueDescriptor to the given long value At DataType level just throws an error lower classes will override
void	setValue(short theValue) Set the value of this DataValueDescriptor to the given short value At DataType level just throws an error lower classes will override
void	setValue(java.lang.String theValue) Set the value of this BooleanDataValue to the given String.
void	setValueFromResultSet(java.sql.ResultSet resultSet, int colNumber, boolean isNullable) Set the value based on the value for the specified DataValueDescriptor from the specified ResultSet.
BooleanDataValue	throwExceptionIfFalse(java.lang.String sqlState, java.lang.String tableName, java.lang.String constraintName) Throw an exception with the given SQLState if this BooleanDataValue is false.
java.lang.String	toString()
static SQLBoolean	truthValue(boolean value) Get a truth value.
static SQLBoolean	truthValue(DataValueDescriptor leftOperand, DataValueDescriptor rightOperand, boolean truth) Return the SQL truth value for a comparison.
static SQLBoolean	truthValue(DataValueDescriptor leftOperand, DataValueDescriptor rightOperand, java.lang.Boolean truth) same as above, but takes a Boolean, if it is null, unknownTruthValue is returned
int	typePrecedence() Each built-in type in JSQL has a precedence.
int	typeToBigDecimal() Implementation for BOOLEAN type.
static SQLBoolean	unknownTruthValue() Return an unknown truth value.
void	writeExternal(java.io.ObjectOutput out)

Methods inherited from class org.apache.derby.iapi.types.DataType

checkHostVariable, cloneHolder, coalesce, compare, compare, compareTo, dataTypeConversion, equals, flip, genericSetObject, getBytes, getDate, getStream, getTime, getTimestamp, getTraceString, getTypeName, hasStream, in, invalidFormat, isNotNull, isNullOp, normalize, outOfRange, readExternalFromArray, setInto, setObjectForCast, setToNull, 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

checkHostVariable, cloneHolder, coalesce, compare, compare, getBytes, getDate, getStream, getTime, getTimestamp, getTraceString, hasStream, in, isNotNull, isNullOp, normalize, readExternalFromArray, setInto, setObjectForCast, setToNull, setValue, setValue, setValue, setValue, setValue, setValue, setValue, setValue, setValue, setValue, setValue, setValue

Field Detail

BOOLEAN_LENGTH

static final int BOOLEAN_LENGTH

See Also:

Constant Field Values

BOOLEAN_TRUE

private static final SQLBoolean BOOLEAN_TRUE

BOOLEAN_FALSE

private static final SQLBoolean BOOLEAN_FALSE

UNKNOWN

static final SQLBoolean UNKNOWN

BASE_MEMORY_USAGE

private static final int BASE_MEMORY_USAGE

value

private boolean value

isnull

private boolean isnull

immutable

private boolean immutable

Constructor Detail

SQLBoolean

public SQLBoolean()

SQLBoolean

public SQLBoolean(boolean val)

SQLBoolean

public SQLBoolean(java.lang.Boolean obj)

SQLBoolean

private SQLBoolean(boolean val,
                   boolean isnull)

Method Detail

isNull

public boolean isNull()

Description copied from interface: Storable

Return whether the value is null or not.

Specified by:

isNull in interface Storable

Returns:

true if the value is null and false otherwise.

getBoolean

public boolean getBoolean()

Description copied from class: DataType

Gets the value in the data value descriptor as a boolean. Throws an exception if the data value is not receivable as a boolean.

Specified by:

getBoolean in interface BooleanDataValue

Specified by:

getBoolean in interface DataValueDescriptor

Overrides:

getBoolean in class DataType

Returns:

The data value as a boolean.

makeInt

private static int makeInt(boolean b)

getByte

public byte getByte()

Description copied from class: DataType

Gets the value in the data value descriptor as a byte. Throws an exception if the data value is not receivable as a byte.

Specified by:

getByte in interface DataValueDescriptor

Overrides:

getByte in class DataType

Returns:

The data value as a byte.

See Also:

DataValueDescriptor.getByte()

getShort

public short getShort()

Description copied from class: DataType

Gets the value in the data value descriptor as a short. Throws an exception if the data value is not receivable as a short.

Specified by:

getShort in interface DataValueDescriptor

Overrides:

getShort in class DataType

Returns:

The data value as a short.

See Also:

DataValueDescriptor.getShort()

getInt

public int getInt()

Description copied from class: DataType

Gets the value in the data value descriptor as a int. Throws an exception if the data value is not receivable as a int.

Specified by:

getInt in interface DataValueDescriptor

Overrides:

getInt in class DataType

Returns:

The data value as a int.

See Also:

DataValueDescriptor.getInt()

getLong

public long getLong()

Description copied from class: DataType

Gets the value in the data value descriptor as a long. Throws an exception if the data value is not receivable as a long.

Specified by:

getLong in interface DataValueDescriptor

Overrides:

getLong in class DataType

Returns:

The data value as a long.

See Also:

DataValueDescriptor.getLong()

getFloat

public float getFloat()

Description copied from class: DataType

Gets the value in the data value descriptor as a float. Throws an exception if the data value is not receivable as a float.

Specified by:

getFloat in interface DataValueDescriptor

Overrides:

getFloat in class DataType

Returns:

The data value as a float.

See Also:

DataValueDescriptor.getFloat()

getDouble

public double getDouble()

Description copied from class: DataType

Gets the value in the data value descriptor as a double. Throws an exception if the data value is not receivable as a double.

Specified by:

getDouble in interface DataValueDescriptor

Overrides:

getDouble in class DataType

Returns:

The data value as a double.

See Also:

DataValueDescriptor.getDouble()

typeToBigDecimal

public int typeToBigDecimal()

Implementation for BOOLEAN type. Convert to a BigDecimal using long

Specified by:

typeToBigDecimal in interface DataValueDescriptor

Overrides:

typeToBigDecimal in class DataType

Returns:

Types.CHAR for String conversion through getString Types.DECIMAL for BigDecimal through getObject or Types.BIGINT for long conversion through getLong

getString

public java.lang.String getString()

Description copied from interface: DataValueDescriptor

Gets the value in the data value descriptor as a String. Throws an exception if the data value is not a string.

Specified by:

getString in interface DataValueDescriptor

Returns:

The data value as a String.

getObject

public java.lang.Object getObject()

Description copied from class: DataType

Gets the value in the data value descriptor as a int. Throws an exception if the data value is not receivable as a int.

Specified by:

getObject in interface DataValueDescriptor

Overrides:

getObject in class DataType

Returns:

The data value as a int.

getLength

public int getLength()

Description copied from interface: DataValueDescriptor

Gets the length of the data value. The meaning of this is implementation-dependent. For string types, it is the number of characters in the string. For numeric types, it is the number of bytes used to store the number. This is the actual length of this value, not the length of the type it was defined as. For example, a VARCHAR value may be shorter than the declared VARCHAR (maximum) length.

Specified by:

getLength in interface DataValueDescriptor

Returns:

The length of the data value

getTypeName

public java.lang.String getTypeName()

Description copied from interface: DataValueDescriptor

Get the SQL name of the datatype

Specified by:

getTypeName in interface DataValueDescriptor

Returns:

The SQL name of the datatype

recycle

public DataValueDescriptor recycle()

Recycle this SQLBoolean object if possible. If the object is immutable, create and return a new object.

Specified by:

recycle in interface DataValueDescriptor

Overrides:

recycle in class DataType

Returns:

a new SQLBoolean if this object is immutable; otherwise, this object with value set to null

getTypeFormatId

public int getTypeFormatId()

Return my format identifier.

Specified by:

getTypeFormatId in interface TypedFormat

Returns:

The identifier. (A UUID stuffed in an array of 16 bytes).

See Also:

TypedFormat.getTypeFormatId()

writeExternal

public void writeExternal(java.io.ObjectOutput out)
                   throws java.io.IOException

Specified by:

writeExternal in interface java.io.Externalizable

Throws:

java.io.IOException

readExternal

public void readExternal(java.io.ObjectInput in)
                  throws java.io.IOException

Specified by:

readExternal in interface java.io.Externalizable

Throws:

java.io.IOException

See Also:

Externalizable.readExternal(java.io.ObjectInput)

restoreToNull

public void restoreToNull()

Description copied from interface: Storable

Restore this object to its (SQL)null value.

Specified by:

restoreToNull in interface Storable

See Also:

Storable.restoreToNull()

compare

public int compare(DataValueDescriptor other)
            throws StandardException

Description copied from interface: DataValueDescriptor

Compare this Orderable with a given Orderable for the purpose of index positioning. This method treats nulls as ordered values - that is, it treats SQL null as equal to null and greater than all other values.

Specified by:

compare in interface DataValueDescriptor

Parameters:

other - The Orderable to compare this one to.

Returns:

<0 - this Orderable is less than other. 0 - this Orderable equals other. >0 - this Orderable is greater than other. The code should not explicitly look for -1, or 1.

Throws:

StandardException - thrown on error

compare

public boolean compare(int op,
                       DataValueDescriptor other,
                       boolean orderedNulls,
                       boolean unknownRV)
                throws StandardException

Description copied from interface: DataValueDescriptor

Compare this Orderable with a given Orderable for the purpose of qualification and sorting. The caller gets to determine how nulls should be treated - they can either be ordered values or unknown values.

Specified by:

compare in interface DataValueDescriptor

Overrides:

compare in class DataType

Parameters:

op - Orderable.ORDER_OP_EQUALS means do an = comparison. Orderable.ORDER_OP_LESSTHAN means compare this < other. Orderable.ORDER_OP_LESSOREQUALS means compare this <= other.

other - The DataValueDescriptor to compare this one to.

orderedNulls - True means to treat nulls as ordered values, that is, treat SQL null as equal to null, and less than all other values. False means to treat nulls as unknown values, that is, the result of any comparison with a null is the UNKNOWN truth value.

unknownRV - The return value to use if the result of the comparison is the UNKNOWN truth value. In other words, if orderedNulls is false, and a null is involved in the comparison, return unknownRV. This parameter is not used orderedNulls is true.

Returns:

true if the comparison is true (duh!)

Throws:

StandardException - thrown on error

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

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

See Also:

DataValueDescriptor.getNewNull()

setValueFromResultSet

public void setValueFromResultSet(java.sql.ResultSet resultSet,
                                  int colNumber,
                                  boolean isNullable)
                           throws java.sql.SQLException

Description copied from interface: DataValueDescriptor

Set the value based on the value for the specified DataValueDescriptor from the specified ResultSet.

Specified by:

setValueFromResultSet in interface DataValueDescriptor

Parameters:

resultSet - The specified ResultSet.

colNumber - The 1-based column # into the resultSet.

isNullable - Whether or not the column is nullable (No need to call wasNull() if not)

Throws:

java.sql.SQLException - Thrown on error

See Also:

DataValueDescriptor.setValueFromResultSet(java.sql.ResultSet, int, boolean)

setInto

public final void setInto(java.sql.PreparedStatement ps,
                          int position)
                   throws java.sql.SQLException

Set the value into a PreparedStatement.

Specified by:

setInto in interface DataValueDescriptor

Overrides:

setInto in class DataType

Throws:

java.sql.SQLException - Error setting value in PreparedStatement

setValue

public void setValue(boolean theValue)

Description copied from class: DataType

Set the value. At DataType level just throws an error lower classes will override

Specified by:

setValue in interface DataValueDescriptor

Overrides:

setValue in class DataType

Parameters:

theValue - Contains the boolean value to set this to

See Also:

BooleanDataValue.setValue(java.lang.Boolean)

setValue

public void setValue(java.lang.Boolean theValue)

Description copied from interface: BooleanDataValue

Set the value of this BooleanDataValue.

Specified by:

setValue in interface BooleanDataValue

Parameters:

theValue - Contains the boolean value to set this BooleanDataValue to. Null means set this BooleanDataValue to null.

setValue

public void setValue(byte theValue)

Description copied from class: DataType

Set the value of this DataValueDescriptor to the given byte value At DataType level just throws an error lower classes will override

Specified by:

setValue in interface DataValueDescriptor

Overrides:

setValue in class DataType

Parameters:

theValue - The value to set this DataValueDescriptor to

setValue

public void setValue(short theValue)

Description copied from class: DataType

Set the value of this DataValueDescriptor to the given short value At DataType level just throws an error lower classes will override

Specified by:

setValue in interface DataValueDescriptor

Overrides:

setValue in class DataType

Parameters:

theValue - The value to set this DataValueDescriptor to

setValue

public void setValue(int theValue)

Description copied from class: DataType

Set the value of this DataValueDescriptor to the given int value At DataType level just throws an error lower classes will override

Specified by:

setValue in interface DataValueDescriptor

Overrides:

setValue in class DataType

Parameters:

theValue - The value to set this DataValueDescriptor to

setValue

public void setValue(long theValue)

Description copied from class: DataType

Set the value of this DataValueDescriptor to the given long value At DataType level just throws an error lower classes will override

Specified by:

setValue in interface DataValueDescriptor

Overrides:

setValue in class DataType

Parameters:

theValue - The value to set this DataValueDescriptor to

setValue

public void setValue(float theValue)

Description copied from class: DataType

Set the value of this DataValueDescriptor to the given float value At DataType level just throws an error lower classes will override

Specified by:

setValue in interface DataValueDescriptor

Overrides:

setValue in class DataType

Parameters:

theValue - The value to set this DataValueDescriptor to

setValue

public void setValue(double theValue)

Description copied from class: DataType

Set the value of this DataValueDescriptor to the given double value At DataType level just throws an error lower classes will override

Specified by:

setValue in interface DataValueDescriptor

Overrides:

setValue in class DataType

Parameters:

theValue - The value to set this DataValueDescriptor to

setBigDecimal

public void setBigDecimal(java.lang.Number bigDecimal)
                   throws StandardException

Description copied from class: DataType

Only to be called when the application sets a value using BigDecimal

Specified by:

setBigDecimal in interface DataValueDescriptor

Overrides:

setBigDecimal in class DataType

Parameters:

bigDecimal - required to be a BigDecimal or null.

Throws:

StandardException

setValue

public void setValue(java.lang.String theValue)
              throws StandardException

Set the value of this BooleanDataValue to the given String. String is trimmed and upcased. If resultant string is not TRUE or FALSE, then an error is thrown.

Specified by:

setValue in interface DataValueDescriptor

Overrides:

setValue in class DataType

Parameters:

theValue - The value to set this BooleanDataValue to

Throws:

StandardException - Thrown on error

setObject

void setObject(java.lang.Object theValue)

Description copied from class: DataType

Set the value from an non-null object. Usually overridden. This implementation throws an exception. The object will have been correctly typed from the call to setObjectForCast.

Overrides:

setObject in class DataType

See Also:

DataValueDescriptor.setValue(int)

setFrom

protected void setFrom(DataValueDescriptor theValue)
                throws StandardException

Description copied from class: DataType

Set the value of this DataValueDescriptor based on the value of the specified DataValueDescriptor.

Overrides:

setFrom in class DataType

Parameters:

theValue - The DataValueDescriptor that holds the value to which we want to set this DataValueDescriptor's value.

Throws:

StandardException

equals

public BooleanDataValue equals(DataValueDescriptor left,
                               DataValueDescriptor right)
                        throws StandardException

The = operator as called from the language module, as opposed to the storage module.

Specified by:

equals in interface DataValueDescriptor

Overrides:

equals in class DataType

Parameters:

left - The value on the left side of the =

right - The value on the right side of the =

Returns:

A SQL boolean value telling whether the two parameters are equal

Throws:

StandardException - Thrown on error

notEquals

public BooleanDataValue notEquals(DataValueDescriptor left,
                                  DataValueDescriptor right)
                           throws StandardException

The <> operator as called from the language module, as opposed to the storage module.

Specified by:

notEquals in interface DataValueDescriptor

Overrides:

notEquals in class DataType

Parameters:

left - The value on the left side of the <>

right - The value on the right side of the <>

Returns:

A SQL boolean value telling whether the two parameters are not equal

Throws:

StandardException - Thrown on error

lessThan

public BooleanDataValue lessThan(DataValueDescriptor left,
                                 DataValueDescriptor right)
                          throws StandardException

The < operator as called from the language module, as opposed to the storage module.

Specified by:

lessThan in interface DataValueDescriptor

Overrides:

lessThan in class DataType

Parameters:

left - The value on the left side of the <

right - The value on the right side of the <

Returns:

A SQL boolean value telling whether the left operand is less than the right operand

Throws:

StandardException - Thrown on error

greaterThan

public BooleanDataValue greaterThan(DataValueDescriptor left,
                                    DataValueDescriptor right)
                             throws StandardException

The > operator as called from the language module, as opposed to the storage module.

Specified by:

greaterThan in interface DataValueDescriptor

Overrides:

greaterThan in class DataType

Parameters:

left - The value on the left side of the >

right - The value on the right side of the >

Returns:

A SQL boolean value telling whether the left operand is greater than the right operand

Throws:

StandardException - Thrown on error

lessOrEquals

public BooleanDataValue lessOrEquals(DataValueDescriptor left,
                                     DataValueDescriptor right)
                              throws StandardException

The <= operator as called from the language module, as opposed to the storage module.

Specified by:

lessOrEquals in interface DataValueDescriptor

Overrides:

lessOrEquals in class DataType

Parameters:

left - The value on the left side of the <=

right - The value on the right side of the <=

Returns:

A SQL boolean value telling whether the left operand is less than or equal to the right operand

Throws:

StandardException - Thrown on error

greaterOrEquals

public BooleanDataValue greaterOrEquals(DataValueDescriptor left,
                                        DataValueDescriptor right)
                                 throws StandardException

The >= operator as called from the language module, as opposed to the storage module.

Specified by:

greaterOrEquals in interface DataValueDescriptor

Overrides:

greaterOrEquals in class DataType

Parameters:

left - The value on the left side of the >=

right - The value on the right side of the >=

Returns:

A SQL boolean value telling whether the left operand is greater than or equal to the right operand

Throws:

StandardException - Thrown on error

and

public BooleanDataValue and(BooleanDataValue otherValue)

The AND operator. This implements SQL semantics for AND with unknown truth values - consult any standard SQL reference for an explanation.

Specified by:

and in interface BooleanDataValue

Parameters:

otherValue - The other boolean to AND with this one

Returns:

this AND otherValue

or

public BooleanDataValue or(BooleanDataValue otherValue)

The OR operator. This implements SQL semantics for OR with unknown truth values - consult any standard SQL reference for an explanation.

Specified by:

or in interface BooleanDataValue

Parameters:

otherValue - The other boolean to OR with this one

Returns:

this OR otherValue

is

public BooleanDataValue is(BooleanDataValue otherValue)

The SQL IS operator - consult any standard SQL reference for an explanation. Implements the following truth table: otherValue | TRUE | FALSE | UNKNOWN this |---------------------------- | TRUE | TRUE | FALSE | FALSE FALSE | FALSE | TRUE | FALSE UNKNOWN | FALSE | FALSE | TRUE

Specified by:

is in interface BooleanDataValue

Parameters:

otherValue - BooleanDataValue to compare to. May be TRUE, FALSE, or UNKNOWN.

Returns:

whether this IS otherValue

isNot

public BooleanDataValue isNot(BooleanDataValue otherValue)

Implements NOT IS. This reverses the sense of the is() call.

Specified by:

isNot in interface BooleanDataValue

Parameters:

otherValue - BooleanDataValue to compare to. May be TRUE, FALSE, or UNKNOWN.

Returns:

NOT( this IS otherValue )

throwExceptionIfFalse

public BooleanDataValue throwExceptionIfFalse(java.lang.String sqlState,
                                              java.lang.String tableName,
                                              java.lang.String constraintName)
                                       throws StandardException

Throw an exception with the given SQLState if this BooleanDataValue is false. This method is useful for evaluating constraints.

Specified by:

throwExceptionIfFalse in interface BooleanDataValue

Parameters:

sqlState - The SQLState of the exception to throw if this SQLBoolean is false.

tableName - The name of the table to include in the exception message.

constraintName - The name of the failed constraint to include in the exception message.

Returns:

this

Throws:

StandardException - Thrown if this BooleanDataValue is false.

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 DataType

Returns:

The precedence of this type.

See Also:

DataValueDescriptor.typePrecedence()

truthValue

public static SQLBoolean truthValue(DataValueDescriptor leftOperand,
                                    DataValueDescriptor rightOperand,
                                    boolean truth)

Return the SQL truth value for a comparison. This method first looks at the operands - if either is null, it returns the unknown truth value. This implements "normal" SQL null semantics, where if any operand is null, the result is null. Note that there are cases where these semantics are incorrect - for example, NULL AND FALSE is supposed to be FALSE, not NULL (the NULL truth value is the same as the UNKNOWN truth value). If neither operand is null, it returns a static final variable containing the SQLBoolean truth value. It returns different values depending on whether the truth value is supposed to be nullable. This method always returns a pre-allocated static final SQLBoolean. This is practical because there are so few possible return values. Using pre-allocated values allows us to avoid constructing new SQLBoolean values during execution.

Parameters:

leftOperand - The left operand of the binary comparison

rightOperand - The right operand of the binary comparison

truth - The truth value of the comparison

Returns:

A SQLBoolean containing the desired truth value.

truthValue

public static SQLBoolean truthValue(DataValueDescriptor leftOperand,
                                    DataValueDescriptor rightOperand,
                                    java.lang.Boolean truth)

same as above, but takes a Boolean, if it is null, unknownTruthValue is returned

truthValue

public static SQLBoolean truthValue(boolean value)

Get a truth value.

Parameters:

value - The value of the SQLBoolean

Returns:

A SQLBoolean with the given truth value

unknownTruthValue

public static SQLBoolean unknownTruthValue()

Return an unknown truth value. Check to be sure the return value is nullable.

Returns:

A SQLBoolean representing the UNKNOWN truth value

equals

public boolean equals(boolean val)

Determine whether this SQLBoolean contains the given boolean value. This method is used by generated code to determine when to do short-circuiting for an AND or OR.

Specified by:

equals in interface BooleanDataValue

Parameters:

val - The value to look for

Returns:

true if the given value equals the value in this SQLBoolean, false if not

getImmutable

public BooleanDataValue getImmutable()

Return an immutable BooleanDataValue with the same value as this.

Specified by:

getImmutable in interface BooleanDataValue

Returns:

An immutable BooleanDataValue with the same value as this.

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object

estimateMemoryUsage

public int estimateMemoryUsage()

Description copied from interface: DataValueDescriptor

Estimate the memory usage in bytes of the data value and the overhead of the class.

Specified by:

estimateMemoryUsage in interface DataValueDescriptor

Returns:

the estimated memory usage