# ParameterMetaData public interface **ParameterMetaData** implements [Wrapper](https://developers.google.com/j2objc/javadoc/jre/reference/java/sql/Wrapper.html) 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. ### Constant Summary |---|---|---| | int | [parameterModeIn](https://developers.google.com/j2objc/javadoc/jre/reference/java/sql/ParameterMetaData.html#parameterModeIn) | The constant indicating that the parameter's mode is IN. | | int | [parameterModeInOut](https://developers.google.com/j2objc/javadoc/jre/reference/java/sql/ParameterMetaData.html#parameterModeInOut) | The constant indicating that the parameter's mode is INOUT. | | int | [parameterModeOut](https://developers.google.com/j2objc/javadoc/jre/reference/java/sql/ParameterMetaData.html#parameterModeOut) | The constant indicating that the parameter's mode is OUT. | | int | [parameterModeUnknown](https://developers.google.com/j2objc/javadoc/jre/reference/java/sql/ParameterMetaData.html#parameterModeUnknown) | The constant indicating that the mode of the parameter is unknown. | | int | [parameterNoNulls](https://developers.google.com/j2objc/javadoc/jre/reference/java/sql/ParameterMetaData.html#parameterNoNulls) | The constant indicating that a parameter will not allow `NULL` values. | | int | [parameterNullable](https://developers.google.com/j2objc/javadoc/jre/reference/java/sql/ParameterMetaData.html#parameterNullable) | The constant indicating that a parameter will allow `NULL` values. | | int | [parameterNullableUnknown](https://developers.google.com/j2objc/javadoc/jre/reference/java/sql/ParameterMetaData.html#parameterNullableUnknown) | The constant indicating that the nullability of a parameter is unknown. | ### Public Method Summary |---|---| | abstract [String](https://developers.google.com/j2objc/javadoc/jre/reference/java/lang/String.html) | [getParameterClassName](https://developers.google.com/j2objc/javadoc/jre/reference/java/sql/ParameterMetaData.html#getParameterClassName(int))(int param) Retrieves the fully-qualified name of the Java class whose instances should be passed to the method `PreparedStatement.setObject`. | | abstract int | [getParameterCount](https://developers.google.com/j2objc/javadoc/jre/reference/java/sql/ParameterMetaData.html#getParameterCount())() Retrieves the number of parameters in the `PreparedStatement` object for which this `ParameterMetaData` object contains information. | | abstract int | [getParameterMode](https://developers.google.com/j2objc/javadoc/jre/reference/java/sql/ParameterMetaData.html#getParameterMode(int))(int param) Retrieves the designated parameter's mode. | | abstract int | [getParameterType](https://developers.google.com/j2objc/javadoc/jre/reference/java/sql/ParameterMetaData.html#getParameterType(int))(int param) Retrieves the designated parameter's SQL type. | | abstract [String](https://developers.google.com/j2objc/javadoc/jre/reference/java/lang/String.html) | [getParameterTypeName](https://developers.google.com/j2objc/javadoc/jre/reference/java/sql/ParameterMetaData.html#getParameterTypeName(int))(int param) Retrieves the designated parameter's database-specific type name. | | abstract int | [getPrecision](https://developers.google.com/j2objc/javadoc/jre/reference/java/sql/ParameterMetaData.html#getPrecision(int))(int param) Retrieves the designated parameter's specified column size. | | abstract int | [getScale](https://developers.google.com/j2objc/javadoc/jre/reference/java/sql/ParameterMetaData.html#getScale(int))(int param) Retrieves the designated parameter's number of digits to right of the decimal point. | | abstract int | [isNullable](https://developers.google.com/j2objc/javadoc/jre/reference/java/sql/ParameterMetaData.html#isNullable(int))(int param) Retrieves whether null values are allowed in the designated parameter. | | abstract boolean | [isSigned](https://developers.google.com/j2objc/javadoc/jre/reference/java/sql/ParameterMetaData.html#isSigned(int))(int param) Retrieves whether values for the designated parameter can be signed numbers. | ### Inherited Method Summary From interface [java.sql.Wrapper](https://developers.google.com/j2objc/javadoc/jre/reference/java/sql/Wrapper.html) |---|---| | abstract boolean | [isWrapperFor](https://developers.google.com/j2objc/javadoc/jre/reference/java/sql/Wrapper.html#isWrapperFor(java.lang.Class))([Class](https://developers.google.com/j2objc/javadoc/jre/reference/java/lang/Class.html)\ iface) Returns true if this either implements the interface argument or is directly or indirectly a wrapper for an object that does. | | abstract \ T | [unwrap](https://developers.google.com/j2objc/javadoc/jre/reference/java/sql/Wrapper.html#unwrap(java.lang.Class))([Class](https://developers.google.com/j2objc/javadoc/jre/reference/java/lang/Class.html)\ iface) Returns an object that implements the given interface to allow access to non-standard methods, or standard methods not exposed by the proxy. | ## Constants #### public static final int **parameterModeIn** The constant indicating that the parameter's mode is IN. Constant Value: 1 #### public static final int **parameterModeInOut** The constant indicating that the parameter's mode is INOUT. Constant Value: 2 #### public static final int **parameterModeOut** The constant indicating that the parameter's mode is OUT. Constant Value: 4 #### public static final int **parameterModeUnknown** The constant indicating that the mode of the parameter is unknown. Constant Value: 0 #### public static final int **parameterNoNulls** The constant indicating that a parameter will not allow `NULL` values. Constant Value: 0 #### public static final int **parameterNullable** The constant indicating that a parameter will allow `NULL` values. Constant Value: 1 #### public static final int **parameterNullableUnknown** The constant indicating that the nullability of a parameter is unknown. Constant Value: 2 ## Public Methods #### public abstract [String](https://developers.google.com/j2objc/javadoc/jre/reference/java/lang/String.html) **getParameterClassName** (int param) Retrieves the fully-qualified name of the Java class whose instances should be passed to the method `PreparedStatement.setObject`. ##### Parameters | param | the first parameter is 1, the second is 2, ... | |---|---| ##### Returns - 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](https://developers.google.com/j2objc/javadoc/jre/reference/java/sql/SQLException.html) | if a database access error occurs | |---|---| #### public abstract int **getParameterCount** () Retrieves the number of parameters in the `PreparedStatement` object for which this `ParameterMetaData` object contains information. ##### Returns - the number of parameters ##### Throws | [SQLException](https://developers.google.com/j2objc/javadoc/jre/reference/java/sql/SQLException.html) | if a database access error occurs | |---|---| #### public abstract int **getParameterMode** (int param) Retrieves the designated parameter's mode. ##### Parameters | param | the first parameter is 1, the second is 2, ... | |---|---| ##### Returns - mode of the parameter; one of `ParameterMetaData.parameterModeIn`, `ParameterMetaData.parameterModeOut`, or `ParameterMetaData.parameterModeInOut` `ParameterMetaData.parameterModeUnknown`. ##### Throws | [SQLException](https://developers.google.com/j2objc/javadoc/jre/reference/java/sql/SQLException.html) | if a database access error occurs | |---|---| #### public abstract int **getParameterType** (int param) Retrieves the designated parameter's SQL type. ##### Parameters | param | the first parameter is 1, the second is 2, ... | |---|---| ##### Returns - SQL type from `java.sql.Types` ##### Throws | [SQLException](https://developers.google.com/j2objc/javadoc/jre/reference/java/sql/SQLException.html) | if a database access error occurs | |---|---| ##### See Also - `https://developers.google.com/j2objc/javadoc/jre/reference/java/sql/Types.html` #### public abstract [String](https://developers.google.com/j2objc/javadoc/jre/reference/java/lang/String.html) **getParameterTypeName** (int param) Retrieves the designated parameter's database-specific type name. ##### Parameters | param | the first parameter is 1, the second is 2, ... | |---|---| ##### Returns - 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](https://developers.google.com/j2objc/javadoc/jre/reference/java/sql/SQLException.html) | if a database access error occurs | |---|---| #### 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 | the first parameter is 1, the second is 2, ... | |---|---| ##### Returns - precision ##### Throws | [SQLException](https://developers.google.com/j2objc/javadoc/jre/reference/java/sql/SQLException.html) | if a database access error occurs | |---|---| #### 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 | the first parameter is 1, the second is 2, ... | |---|---| ##### Returns - scale ##### Throws | [SQLException](https://developers.google.com/j2objc/javadoc/jre/reference/java/sql/SQLException.html) | if a database access error occurs | |---|---| #### public abstract int **isNullable** (int param) Retrieves whether null values are allowed in the designated parameter. ##### Parameters | param | the first parameter is 1, the second is 2, ... | |---|---| ##### Returns - the nullability status of the given parameter; one of `ParameterMetaData.parameterNoNulls`, `ParameterMetaData.parameterNullable`, or `ParameterMetaData.parameterNullableUnknown` ##### Throws | [SQLException](https://developers.google.com/j2objc/javadoc/jre/reference/java/sql/SQLException.html) | if a database access error occurs | |---|---| #### public abstract boolean **isSigned** (int param) Retrieves whether values for the designated parameter can be signed numbers. ##### Parameters | param | the first parameter is 1, the second is 2, ... | |---|---| ##### Returns - `true` if so; `false` otherwise ##### Throws | [SQLException](https://developers.google.com/j2objc/javadoc/jre/reference/java/sql/SQLException.html) | if a database access error occurs | |---|---|