public class BeanPropertyRowMapper<T> extends Object implements RowMapper<T>
RowMapper
implementation that converts a row into a new instance
of the specified mapped target class. The mapped target class must be a
top-level class and it must have a default or no-arg constructor.
Column values are mapped based on matching the column name as obtained from result set metadata to public setters for the corresponding properties. The names are matched either directly or by transforming a name separating the parts with underscores to the same name using "camel" case.
Mapping is provided for fields in the target class for many common types, e.g.:
String, boolean, Boolean, byte, Byte, short, Short, int, Integer, long, Long,
float, Float, double, Double, BigDecimal, java.util.Date
, etc.
To facilitate mapping between columns and fields that don't have matching names, try using column aliases in the SQL statement like "select fname as first_name from customer".
For 'null' values read from the databasem, we will attempt to call the setter, but in the case of Java primitives, this causes a TypeMismatchException. This class can be configured (using the primitivesDefaultedForNullValue property) to trap this exception and use the primitives default value. Be aware that if you use the values from the generated bean to update the database the primitive value will have been set to the primitive's default value instead of null.
Please note that this class is designed to provide convenience rather than high performance.
For best performance, consider using a custom RowMapper
implementation.
Modifier and Type | Field and Description |
---|---|
protected Log |
logger
Logger available to subclasses
|
Constructor and Description |
---|
BeanPropertyRowMapper()
Create a new
BeanPropertyRowMapper for bean-style configuration. |
BeanPropertyRowMapper(Class<T> mappedClass)
Create a new
BeanPropertyRowMapper , accepting unpopulated
properties in the target bean. |
BeanPropertyRowMapper(Class<T> mappedClass,
boolean checkFullyPopulated)
Create a new
BeanPropertyRowMapper . |
Modifier and Type | Method and Description |
---|---|
protected Object |
getColumnValue(ResultSet rs,
int index,
PropertyDescriptor pd)
Retrieve a JDBC object value for the specified column.
|
Class<T> |
getMappedClass()
Get the class that we are mapping to.
|
protected void |
initBeanWrapper(BeanWrapper bw)
Initialize the given BeanWrapper to be used for row mapping.
|
protected void |
initialize(Class<T> mappedClass)
Initialize the mapping metadata for the given class.
|
boolean |
isCheckFullyPopulated()
Return whether we're strictly validating that all bean properties have been
mapped from corresponding database fields.
|
boolean |
isPrimitivesDefaultedForNullValue()
Return whether we're defaulting Java primitives in the case of mapping a null value
from corresponding database fields.
|
protected String |
lowerCaseName(String name)
Convert the given name to lower case.
|
T |
mapRow(ResultSet rs,
int rowNumber)
Extract the values for all columns in the current row.
|
static <T> BeanPropertyRowMapper<T> |
newInstance(Class<T> mappedClass)
Static factory method to create a new
BeanPropertyRowMapper
(with the mapped class specified only once). |
void |
setCheckFullyPopulated(boolean checkFullyPopulated)
Set whether we're strictly validating that all bean properties have been mapped
from corresponding database fields.
|
void |
setMappedClass(Class<T> mappedClass)
Set the class that each row should be mapped to.
|
void |
setPrimitivesDefaultedForNullValue(boolean primitivesDefaultedForNullValue)
Set whether we're defaulting Java primitives in the case of mapping a null value
from corresponding database fields.
|
protected String |
underscoreName(String name)
Convert a name in camelCase to an underscored name in lower case.
|
protected final Log logger
public BeanPropertyRowMapper()
BeanPropertyRowMapper
for bean-style configuration.public BeanPropertyRowMapper(Class<T> mappedClass)
BeanPropertyRowMapper
, accepting unpopulated
properties in the target bean.
Consider using the newInstance(java.lang.Class<T>)
factory method instead,
which allows for specifying the mapped type once only.
mappedClass
- the class that each row should be mapped topublic BeanPropertyRowMapper(Class<T> mappedClass, boolean checkFullyPopulated)
BeanPropertyRowMapper
.mappedClass
- the class that each row should be mapped tocheckFullyPopulated
- whether we're strictly validating that
all bean properties have been mapped from corresponding database fieldspublic void setMappedClass(Class<T> mappedClass)
public void setCheckFullyPopulated(boolean checkFullyPopulated)
Default is false
, accepting unpopulated properties in the target bean.
public boolean isCheckFullyPopulated()
public void setPrimitivesDefaultedForNullValue(boolean primitivesDefaultedForNullValue)
Default is false
, throwing an exception when nulls are mapped to Java primitives.
public boolean isPrimitivesDefaultedForNullValue()
protected void initialize(Class<T> mappedClass)
mappedClass
- the mapped classprotected String underscoreName(String name)
name
- the original namelowerCaseName(java.lang.String)
protected String lowerCaseName(String name)
name
- the original namepublic T mapRow(ResultSet rs, int rowNumber) throws SQLException
Utilizes public setters and result set metadata.
mapRow
in interface RowMapper<T>
rs
- the ResultSet to map (pre-initialized for the current row)rowNumber
- the number of the current rowSQLException
- if a SQLException is encountered getting
column values (that is, there's no need to catch SQLException)ResultSetMetaData
protected void initBeanWrapper(BeanWrapper bw)
The default implementation is empty. Can be overridden in subclasses.
bw
- the BeanWrapper to initializeprotected Object getColumnValue(ResultSet rs, int index, PropertyDescriptor pd) throws SQLException
The default implementation calls
JdbcUtils.getResultSetValue(java.sql.ResultSet, int, Class)
.
Subclasses may override this to check specific value types upfront,
or to post-process values return from getResultSetValue
.
rs
- is the ResultSet holding the dataindex
- is the column indexpd
- the bean property that each result object is expected to match
(or null
if none specified)SQLException
- in case of extraction failureJdbcUtils.getResultSetValue(java.sql.ResultSet, int, Class)
public static <T> BeanPropertyRowMapper<T> newInstance(Class<T> mappedClass)
BeanPropertyRowMapper
(with the mapped class specified only once).mappedClass
- the class that each row should be mapped to