adql.db

Class DBType

java.lang.Object

adql.db.DBType

public class DBType
extends java.lang.Object

Describe a full column type as it is described in the IVOA document of TAP. Thus, this object contains 2 attributes: type (or datatype) and length (or size).

The length/size may be not defined ; in this case, its value is set to NO_LENGTH or is negative or null.

All datatypes declared in the IVOA recommendation document of TAP are listed in an enumeration type: DBType.DBDatatype. It is used to set the attribute type/datatype of this class.

Since:

1.3

Version:

1.4 (07/2016)

Author:

Grégory Mantelet (ARI)

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	DBType.DBDatatype List of all datatypes declared in the IVOA recommendation of TAP (in the section UPLOAD).

Field Summary

Fields

Modifier and Type	Field and Description
int	length The length parameter (only few datatypes need this parameter: char, varchar, binary and varbinary).
static int	NO_LENGTH Special value in case no length/size is specified.
DBType.DBDatatype	type Datatype of a column.

Constructor Summary

Constructors

Constructor and Description
DBType(DBType.DBDatatype datatype) Build a TAP column type by specifying a datatype.
DBType(DBType.DBDatatype datatype, int length) Build a TAP column type by specifying a datatype and a length (needed only for datatypes like char, varchar, binary and varbinary).

Method Summary

Modifier and Type	Method and Description
boolean	isBinary() Tells whether this type is a list of bytes.
boolean	isCompatible(DBType t) Tell whether this DBType is compatible with the given one.
boolean	isGeometry() Tells whether this type is a geometrical region.
boolean	isNumeric() Tells whether this type is a numeric.
boolean	isString() Tells whether this type is about characters.
boolean	isUnknown() Tell whether this type has been resolved or not.
java.lang.String	toString()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

NO_LENGTH

public static final int NO_LENGTH

Special value in case no length/size is specified.

See Also:

Constant Field Values

type

public final DBType.DBDatatype type

Datatype of a column.

length

public final int length

The length parameter (only few datatypes need this parameter: char, varchar, binary and varbinary).

Constructor Detail

DBType

public DBType(DBType.DBDatatype datatype)

Build a TAP column type by specifying a datatype.

Parameters:

datatype - Column datatype.

DBType

public DBType(DBType.DBDatatype datatype,
              int length)

Build a TAP column type by specifying a datatype and a length (needed only for datatypes like char, varchar, binary and varbinary).

Parameters:

datatype - Column datatype.

length - Length of the column value (needed only for datatypes like char, varchar, binary and varbinary).

Method Detail

isNumeric

public boolean isNumeric()

Tells whether this type is a numeric.

Concerned types: SMALLINT, INTEGER, BIGINT, REAL, DOUBLE, BINARY, VARBINARY and BLOB.

Important note: Since UNKNOWN is an unresolved type, it can potentially be anything. But, in order to avoid incorrect operation while expecting a numeric although the type is unknown and is in fact not really a numeric, this function will return false if the type is UNKNOWN BUT true if UNKNOWN_NUMERIC.

Returns:

true if this type is a numeric, false otherwise.

isBinary

public boolean isBinary()

Tells whether this type is a list of bytes.

Concerned types: BINARY, VARBINARY and BLOB.

Important note: Since UNKNOWN is an unresolved type, it can potentially be anything. But, in order to avoid incorrect operation while expecting a binary although the type is unknown and is in fact not really a binary, this function will return false if the type is UNKNOWN or UNKNOWN_NUMERIC.

Returns:

true if this type is a binary, false otherwise.

isString

public boolean isString()

Tells whether this type is about characters.

Concerned types: CHAR, VARCHAR, CLOB and TIMESTAMP.

Important note: Since UNKNOWN is an unresolved type, it can potentially be anything. But, in order to avoid incorrect operation while expecting a string although the type is unknown and is in fact not really a string, this function will return false if the type is UNKNOWN or UNKNOWN_NUMERIC

Returns:

true if this type is a string, false otherwise.

isGeometry

public boolean isGeometry()

Tells whether this type is a geometrical region.

Concerned types: POINT and REGION.

Important note: Since UNKNOWN is an unresolved type, it can potentially be anything. But, in order to avoid incorrect operation while expecting a geometry although the type is unknown and is in fact not really a geometry, this function will return false if the type is UNKNOWN or UNKNOWN_NUMERIC.

Returns:

true if this type is a geometry, false otherwise.

isUnknown

public boolean isUnknown()

Tell whether this type has been resolved or not.

Concerned types: UNKNOWN and UNKNOWN_NUMERIC.

Returns:

true if this type has NOT been resolved, false otherwise.

Since:

1.4

isCompatible

public boolean isCompatible(DBType t)

Tell whether this DBType is compatible with the given one.

Two DBTypes are said compatible if they are both binary, numeric, geometric or string. If one of the two types is unknown or unknown_numeric, this function will consider them as compatible and will return true.

Parameters:

t - The type to compare to.

Returns:

true if this type is compatible with the given one, false otherwise.

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object