类 BeanPropertyRowMapper<T>
- java.lang.Object
- org.springframework.jdbc.core.BeanPropertyRowMapper<T>
- 类型参数:
T
- the result type
- 所有已实现的接口:
RowMapper<T>
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 meta-data 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 database, 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.- 从以下版本开始:
- 2.5
- 作者:
- Thomas Risberg, Juergen Hoeller
构造器概要
构造器 构造器 说明 BeanPropertyRowMapper()
Create a newBeanPropertyRowMapper
for bean-style configuration.BeanPropertyRowMapper(Class<T> mappedClass)
Create a newBeanPropertyRowMapper
, accepting unpopulated properties in the target bean.BeanPropertyRowMapper(Class<T> mappedClass, boolean checkFullyPopulated)
Create a newBeanPropertyRowMapper
.
方法概要
所有方法 静态方法 实例方法 具体方法 修饰符和类型 方法 说明 protected Object
getColumnValue(ResultSet rs, int index, PropertyDescriptor pd)
Retrieve a JDBC object value for the specified column.ConversionService
getConversionService()
Return aConversionService
for binding JDBC values to bean properties, ornull
if none.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 meta-data 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 newBeanPropertyRowMapper
.static <T> BeanPropertyRowMapper<T>
newInstance(Class<T> mappedClass, ConversionService conversionService)
Static factory method to create a newBeanPropertyRowMapper
.void
setCheckFullyPopulated(boolean checkFullyPopulated)
Set whether we're strictly validating that all bean properties have been mapped from corresponding database fields.void
setConversionService(ConversionService conversionService)
Set aConversionService
for binding JDBC values to bean properties, ornull
for none.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.
构造器详细资料
BeanPropertyRowMapper
public BeanPropertyRowMapper()
Create a newBeanPropertyRowMapper
for bean-style configuration.
BeanPropertyRowMapper
public BeanPropertyRowMapper(Class<T> mappedClass)
Create a newBeanPropertyRowMapper
, accepting unpopulated properties in the target bean.- 参数:
mappedClass
- the class that each row should be mapped to
BeanPropertyRowMapper
public BeanPropertyRowMapper(Class<T> mappedClass, boolean checkFullyPopulated)
Create a newBeanPropertyRowMapper
.- 参数:
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 fields
方法详细资料
setMappedClass
public void setMappedClass(Class<T> mappedClass)
Set the class that each row should be mapped to.
getMappedClass
@Nullable public final Class<T> getMappedClass()
Get the class that we are mapping to.
setCheckFullyPopulated
public void setCheckFullyPopulated(boolean checkFullyPopulated)
Set whether we're strictly validating that all bean properties have been mapped from corresponding database fields.Default is
false
, accepting unpopulated properties in the target bean.
isCheckFullyPopulated
public boolean isCheckFullyPopulated()
Return whether we're strictly validating that all bean properties have been mapped from corresponding database fields.
setPrimitivesDefaultedForNullValue
public void setPrimitivesDefaultedForNullValue(boolean primitivesDefaultedForNullValue)
Set whether we're defaulting Java primitives in the case of mapping a null value from corresponding database fields.Default is
false
, throwing an exception when nulls are mapped to Java primitives.
isPrimitivesDefaultedForNullValue
public boolean isPrimitivesDefaultedForNullValue()
Return whether we're defaulting Java primitives in the case of mapping a null value from corresponding database fields.
setConversionService
public void setConversionService(@Nullable ConversionService conversionService)
Set aConversionService
for binding JDBC values to bean properties, ornull
for none.Default is a
DefaultConversionService
, as of Spring 4.3. This provides support forjava.time
conversion and other special types.- 从以下版本开始:
- 4.3
- 另请参阅:
initBeanWrapper(BeanWrapper)
getConversionService
@Nullable public ConversionService getConversionService()
Return aConversionService
for binding JDBC values to bean properties, ornull
if none.- 从以下版本开始:
- 4.3
initialize
protected void initialize(Class<T> mappedClass)
Initialize the mapping meta-data for the given class.- 参数:
mappedClass
- the mapped class
underscoreName
protected String underscoreName(String name)
Convert a name in camelCase to an underscored name in lower case. Any upper case letters are converted to lower case with a preceding underscore.- 参数:
name
- the original name- 返回:
- the converted name
- 从以下版本开始:
- 4.2
- 另请参阅:
lowerCaseName(java.lang.String)
lowerCaseName
protected String lowerCaseName(String name)
Convert the given name to lower case. By default, conversions will happen within the US locale.- 参数:
name
- the original name- 返回:
- the converted name
- 从以下版本开始:
- 4.2
mapRow
public T mapRow(ResultSet rs, int rowNumber) throws SQLException
Extract the values for all columns in the current row.Utilizes public setters and result set meta-data.
- 指定者:
mapRow
在接口中RowMapper<T>
- 参数:
rs
- the ResultSet to map (pre-initialized for the current row)rowNumber
- the number of the current row- 返回:
- the result object for the current row (may be
null
) - 抛出:
SQLException
- if an SQLException is encountered getting column values (that is, there's no need to catch SQLException)- 另请参阅:
ResultSetMetaData
initBeanWrapper
protected void initBeanWrapper(BeanWrapper bw)
Initialize the given BeanWrapper to be used for row mapping. To be called for each row.The default implementation applies the configured
ConversionService
, if any. Can be overridden in subclasses.- 参数:
bw
- the BeanWrapper to initialize- 另请参阅:
getConversionService()
,ConfigurablePropertyAccessor.setConversionService(org.springframework.core.convert.ConversionService)
getColumnValue
@Nullable protected Object getColumnValue(ResultSet rs, int index, PropertyDescriptor pd) throws SQLException
Retrieve a JDBC object value for the specified column.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 fromgetResultSetValue
.- 参数:
rs
- is the ResultSet holding the dataindex
- is the column indexpd
- the bean property that each result object is expected to match- 返回:
- the Object value
- 抛出:
SQLException
- in case of extraction failure- 另请参阅:
JdbcUtils.getResultSetValue(java.sql.ResultSet, int, Class)
newInstance
public static <T> BeanPropertyRowMapper<T> newInstance(Class<T> mappedClass)
Static factory method to create a newBeanPropertyRowMapper
.- 参数:
mappedClass
- the class that each row should be mapped to- 另请参阅:
newInstance(Class, ConversionService)
newInstance
public static <T> BeanPropertyRowMapper<T> newInstance(Class<T> mappedClass, @Nullable ConversionService conversionService)
Static factory method to create a newBeanPropertyRowMapper
.- 参数:
mappedClass
- the class that each row should be mapped toconversionService
- theConversionService
for binding JDBC values to bean properties, ornull
for none- 从以下版本开始:
- 5.2.3
- 另请参阅:
newInstance(Class)
,setConversionService(org.springframework.core.convert.ConversionService)