ParameterMetaData
public
interface
ParameterMetaData
implements
Wrapper
java.sql.ParameterMetaData |
An object that can be used to get information about the types
and properties for each parameter marker in a
PreparedStatement
object. For some queries and driver
implementations, the data that would be returned by a ParameterMetaData
object may not be available until the PreparedStatement
has
been executed.
Some driver implementations may not be able to provide information about the
types and properties for each parameter marker in a CallableStatement
object.
Summary
Constants | |
---|---|
int |
parameterModeIn
The constant indicating that the parameter's mode is IN. |
int |
parameterModeInOut
The constant indicating that the parameter's mode is INOUT. |
int |
parameterModeOut
The constant indicating that the parameter's mode is OUT. |
int |
parameterModeUnknown
The constant indicating that the mode of the parameter is unknown. |
int |
parameterNoNulls
The constant indicating that a
parameter will not allow |
int |
parameterNullable
The constant indicating that a
parameter will allow |
int |
parameterNullableUnknown
The constant indicating that the nullability of a parameter is unknown. |
Public methods | |
---|---|
abstract
String
|
getParameterClassName(int param)
Retrieves the fully-qualified name of the Java class whose instances
should be passed to the method |
abstract
int
|
getParameterCount()
Retrieves the number of parameters in the |
abstract
int
|
getParameterMode(int param)
Retrieves the designated parameter's mode. |
abstract
int
|
getParameterType(int param)
Retrieves the designated parameter's SQL type. |
abstract
String
|
getParameterTypeName(int param)
Retrieves the designated parameter's database-specific type name. |
abstract
int
|
getPrecision(int param)
Retrieves the designated parameter's specified column size. |
abstract
int
|
getScale(int param)
Retrieves the designated parameter's number of digits to right of the decimal point. |
abstract
int
|
isNullable(int param)
Retrieves whether null values are allowed in the designated parameter. |
abstract
boolean
|
isSigned(int param)
Retrieves whether values for the designated parameter can be signed numbers. |
Inherited methods | |
---|---|
Constants
parameterModeIn
public static final int parameterModeIn
The constant indicating that the parameter's mode is IN.
Constant Value: 1 (0x00000001)
parameterModeInOut
public static final int parameterModeInOut
The constant indicating that the parameter's mode is INOUT.
Constant Value: 2 (0x00000002)
parameterModeOut
public static final int parameterModeOut
The constant indicating that the parameter's mode is OUT.
Constant Value: 4 (0x00000004)
parameterModeUnknown
public static final int parameterModeUnknown
The constant indicating that the mode of the parameter is unknown.
Constant Value: 0 (0x00000000)
parameterNoNulls
public static final int parameterNoNulls
The constant indicating that a
parameter will not allow NULL
values.
Constant Value: 0 (0x00000000)
parameterNullable
public static final int parameterNullable
The constant indicating that a
parameter will allow NULL
values.
Constant Value: 1 (0x00000001)
parameterNullableUnknown
public static final int parameterNullableUnknown
The constant indicating that the nullability of a parameter is unknown.
Constant Value: 2 (0x00000002)
Public methods
getParameterClassName
public abstract String getParameterClassName (int param)
Retrieves the fully-qualified name of the Java class whose instances
should be passed to the method PreparedStatement.setObject
.
Parameters | |
---|---|
param |
int : the first parameter is 1, the second is 2, ... |
Returns | |
---|---|
String |
the fully-qualified name of the class in the Java programming
language that would be used by the method
PreparedStatement.setObject to set the value
in the specified parameter. This is the class name used
for custom mapping. |
Throws | |
---|---|
SQLException |
if a database access error occurs |
getParameterCount
public abstract int getParameterCount ()
Retrieves the number of parameters in the PreparedStatement
object for which this ParameterMetaData
object contains
information.
Returns | |
---|---|
int |
the number of parameters |
Throws | |
---|---|
SQLException |
if a database access error occurs |
getParameterMode
public abstract int getParameterMode (int param)
Retrieves the designated parameter's mode.
Parameters | |
---|---|
param |
int : the first parameter is 1, the second is 2, ... |
Returns | |
---|---|
int |
mode of the parameter; one of
ParameterMetaData.parameterModeIn ,
ParameterMetaData.parameterModeOut , or
ParameterMetaData.parameterModeInOut
ParameterMetaData.parameterModeUnknown . |
Throws | |
---|---|
SQLException |
if a database access error occurs |
getParameterType
public abstract int getParameterType (int param)
Retrieves the designated parameter's SQL type.
Parameters | |
---|---|
param |
int : the first parameter is 1, the second is 2, ... |
Returns | |
---|---|
int |
SQL type from java.sql.Types |
Throws | |
---|---|
SQLException |
if a database access error occurs |
See also:
getParameterTypeName
public abstract String getParameterTypeName (int param)
Retrieves the designated parameter's database-specific type name.
Parameters | |
---|---|
param |
int : the first parameter is 1, the second is 2, ... |
Returns | |
---|---|
String |
type the name used by the database. If the parameter type is a user-defined type, then a fully-qualified type name is returned. |
Throws | |
---|---|
SQLException |
if a database access error occurs |
getPrecision
public abstract int getPrecision (int param)
Retrieves the designated parameter's specified column size.
The returned value represents the maximum column size for the given parameter. For numeric data, this is the maximum precision. For character data, this is the length in characters. For datetime datatypes, this is the length in characters of the String representation (assuming the maximum allowed precision of the fractional seconds component). For binary data, this is the length in bytes. For the ROWID datatype, this is the length in bytes. 0 is returned for data types where the column size is not applicable.
Parameters | |
---|---|
param |
int : the first parameter is 1, the second is 2, ... |
Returns | |
---|---|
int |
precision |
Throws | |
---|---|
SQLException |
if a database access error occurs |
getScale
public abstract int getScale (int param)
Retrieves the designated parameter's number of digits to right of the decimal point. 0 is returned for data types where the scale is not applicable.
Parameters | |
---|---|
param |
int : the first parameter is 1, the second is 2, ... |
Returns | |
---|---|
int |
scale |
Throws | |
---|---|
SQLException |
if a database access error occurs |
isNullable
public abstract int isNullable (int param)
Retrieves whether null values are allowed in the designated parameter.
Parameters | |
---|---|
param |
int : the first parameter is 1, the second is 2, ... |
Returns | |
---|---|
int |
the nullability status of the given parameter; one of
ParameterMetaData.parameterNoNulls ,
ParameterMetaData.parameterNullable , or
ParameterMetaData.parameterNullableUnknown |
Throws | |
---|---|
SQLException |
if a database access error occurs |
isSigned
public abstract boolean isSigned (int param)
Retrieves whether values for the designated parameter can be signed numbers.
Parameters | |
---|---|
param |
int : the first parameter is 1, the second is 2, ... |
Returns | |
---|---|
boolean |
true if so; false otherwise |
Throws | |
---|---|
SQLException |
if a database access error occurs |