Liquibase 4.26.0 · liquibase.executor.jvm.SingleColumnRowMapper

Modifier and Type	Field and Description
private Class<T>	requiredType

Access	Constructor and Description
public	SingleColumnRowMapper() Create a new SingleColumnRowMapper.
public	SingleColumnRowMapper(Class<T> the type that each result object is expected to match requiredType) Create a new SingleColumnRowMapper.

Method Summary

Modifier and Type	Method and Description
protected Object	Returns: the converted value convertValueToRequiredType(Object the column value as extracted from `getColumnValue()` (never `null`) value, Class<T> the type that each result object is expected to match (never `null`) requiredType) Convert the given column value to the specified required type.
protected Object	Returns: the Object value getColumnValue(ResultSet is the ResultSet holding the data rs, int is the column index index, Class<T> the type that each result object is expected to match (or `null` if none specified) requiredType) Retrieve a JDBC object value for the specified column.
protected Object	Returns: the Object value getColumnValue(ResultSet is the ResultSet holding the data rs, int is the column index index) Retrieve a JDBC object value for the specified column, using the most appropriate value type.
public Object	mapRow(ResultSet the ResultSet to map (pre-initialized for the current row) rs, int the number of the current row rowNum) Implements liquibase.executor.jvm.RowMapper.mapRow. Extract a value for the single column in the current row.
public void	setRequiredType(Class<T> requiredType) Set the type that each result object is expected to match.

Inherited from java.lang.Object:: clone equals finalize getClass hashCode notify notifyAll toString wait wait wait

requiredType	back to summary
private Class<T> requiredType

SingleColumnRowMapper	back to summary
public SingleColumnRowMapper() Create a new SingleColumnRowMapper. See Also `setRequiredType`

SingleColumnRowMapper	back to summary
public SingleColumnRowMapper(Class<T> requiredType) Create a new SingleColumnRowMapper. Parameters requiredType:Class<T> the type that each result object is expected to match

Method Detail

convertValueToRequiredType back to summary

convertValueToRequiredType	back to summary
protected Object convertValueToRequiredType(Object value, Class<T> requiredType) Convert the given column value to the specified required type. Only called if the extracted column value does not match already. If the required type is String, the value will simply get stringified via `toString()`. In case of a Number, the value will be converted into a Number, either through number conversion or through String parsing (depending on the value type). Parameters value:Object the column value as extracted from `getColumnValue()` (never `null`) requiredType:Class<T> the type that each result object is expected to match (never `null`) Returns:Object the converted value See Also `getColumnValue(java.sql.ResultSet, int, Class)`

protected Object convertValueToRequiredType(Object value, Class<T> requiredType)

Convert the given column value to the specified required type. Only called if the extracted column value does not match already.

If the required type is String, the value will simply get stringified via toString(). In case of a Number, the value will be converted into a Number, either through number conversion or through String parsing (depending on the value type).

Parameters

value:Object: the column value as extracted from getColumnValue() (never null)
requiredType:Class<T>: the type that each result object is expected to match (never null)

Returns:Object

the converted value

getColumnValue back to summary

getColumnValue	back to summary
protected Object getColumnValue(ResultSet rs, int index, Class<T> requiredType) throws SQLException Retrieve a JDBC object value for the specified column. The default implementation calls `ResultSet.getString(index)` etc for all standard value types (String, Boolean, number types, date types, etc). It calls `ResultSet.getObject(index)` else. If no required type has been specified, this method delegates to `getColumnValue(rs, index)`, which basically calls `ResultSet.getObject(index)` but applies some additional default conversion to appropriate value types. Explicit extraction of a String is necessary to properly extract an Oracle RAW value as a String, for example. For the other given types, it is also recommendable to extract the desired types explicitly, to let the JDBC driver perform appropriate (potentially database-specific) conversion. Parameters rs:ResultSet is the ResultSet holding the data index:int is the column index requiredType:Class<T> the type that each result object is expected to match (or `null` if none specified) Returns:Object the Object value See Also `java.sql.ResultSet#getString(int)`, `java.sql.ResultSet#getObject(int)`, `getColumnValue(java.sql.ResultSet, int)`

protected Object getColumnValue(ResultSet rs, int index, Class<T> requiredType) throws SQLException

Retrieve a JDBC object value for the specified column.

The default implementation calls ResultSet.getString(index) etc for all standard value types (String, Boolean, number types, date types, etc). It calls ResultSet.getObject(index) else.

If no required type has been specified, this method delegates to getColumnValue(rs, index), which basically calls ResultSet.getObject(index) but applies some additional default conversion to appropriate value types.

Explicit extraction of a String is necessary to properly extract an Oracle RAW value as a String, for example. For the other given types, it is also recommendable to extract the desired types explicitly, to let the JDBC driver perform appropriate (potentially database-specific) conversion.

Parameters

rs:ResultSet: is the ResultSet holding the data
index:int: is the column index
requiredType:Class<T>: the type that each result object is expected to match (or null if none specified)

Returns:Object

the Object value

getColumnValue back to summary

getColumnValue	back to summary
protected Object getColumnValue(ResultSet rs, int index) throws SQLException Retrieve a JDBC object value for the specified column, using the most appropriate value type. Called if no required type has been specified. The default implementation delegates to `JdbcUtils.getResultSetValue()`, which uses the `ResultSet.getObject(index)` method. Additionally, it includes a "hack" to get around Oracle returning a non-standard object for their TIMESTAMP datatype. See the `JdbcUtils#getResultSetValue()` javadoc for details. Parameters rs:ResultSet is the ResultSet holding the data index:int is the column index Returns:Object the Object value

protected Object getColumnValue(ResultSet rs, int index) throws SQLException

Retrieve a JDBC object value for the specified column, using the most appropriate value type. Called if no required type has been specified.

The default implementation delegates to JdbcUtils.getResultSetValue(), which uses the ResultSet.getObject(index) method. Additionally, it includes a "hack" to get around Oracle returning a non-standard object for their TIMESTAMP datatype. See the JdbcUtils#getResultSetValue() javadoc for details.

Parameters

rs:ResultSet: is the ResultSet holding the data
index:int: is the column index

Returns:Object

the Object value

mapRow back to summary

mapRow	back to summary
public Object mapRow(ResultSet rs, int rowNum) throws SQLException Implements liquibase.executor.jvm.RowMapper.mapRow. Extract a value for the single column in the current row. Validates that there is only one column selected, then delegates to `getColumnValue()` and also `convertValueToRequiredType`, if necessary. Parameters rs:ResultSet Doc from liquibase.executor.jvm.RowMapper.mapRow. the ResultSet to map (pre-initialized for the current row) rowNum:int Doc from liquibase.executor.jvm.RowMapper.mapRow. the number of the current row Returns:Object Doc from liquibase.executor.jvm.RowMapper.mapRow. the result object for the current row Annotations @Override Exceptions SQLException: Doc from liquibase.executor.jvm.RowMapper.mapRow. if a SQLException is encountered getting column values (that is, there's no need to catch SQLException) See Also `java.sql.ResultSetMetaData#getColumnCount()`, `getColumnValue(java.sql.ResultSet, int, Class)`, `convertValueToRequiredType(Object, Class)`

public Object mapRow(ResultSet rs, int rowNum) throws SQLException

Implements liquibase.executor.jvm.RowMapper.mapRow.

Extract a value for the single column in the current row.

Validates that there is only one column selected, then delegates to getColumnValue() and also convertValueToRequiredType, if necessary.

Parameters

rs:ResultSet

Doc from liquibase.executor.jvm.RowMapper.mapRow.

the ResultSet to map (pre-initialized for the current row)

rowNum:int

Doc from liquibase.executor.jvm.RowMapper.mapRow.

the number of the current row

Returns:Object

Doc from liquibase.executor.jvm.RowMapper.mapRow.

the result object for the current row

Annotations

@Override

Exceptions

SQLException:

Doc from liquibase.executor.jvm.RowMapper.mapRow.

if a SQLException is encountered getting column values (that is, there's no need to catch SQLException)

setRequiredType	back to summary
public void setRequiredType(Class<T> requiredType) Set the type that each result object is expected to match. If not specified, the column value will be exposed as returned by the JDBC driver.

setRequiredType

back to summary

public void setRequiredType(Class<T> requiredType)

Set the type that each result object is expected to match.

If not specified, the column value will be exposed as returned by the JDBC driver.

pack-priv Class SingleColumnRowMapper

Field Summary

Constructor Summary

Method Summary

Field Detail

Constructor Detail

Method Detail