com.github.braisdom.objsql.jdbc.handlers

类 BeanMapHandler<K,V>

java.lang.Object

com.github.braisdom.objsql.jdbc.handlers.AbstractKeyedHandler<K,V>

com.github.braisdom.objsql.jdbc.handlers.BeanMapHandler<K,V>

类型参数:

K - the type of keys maintained by the returned map

V - the type of the bean

所有已实现的接口:

ResultSetHandler<Map<K,V>>

public class BeanMapHandler<K,V>
extends AbstractKeyedHandler<K,V>

ResultSetHandler implementation that returns a Map of Beans. ResultSet rows are converted into Beans which are then stored in a Map under the given key.

If you had a Person table with a primary key column called ID, you could retrieve rows from the table like this:

 ResultSetHandler<Map<Long, Person>> h = new BeanMapdHandler<Long, Person>(Person.class, "id");
 Map&ltLong, Person> found = queryRunner.query("project id, name, age from person", h);
 Person jane = found.get(1L); // jane's id is 1
 String janesName = jane.getName();
 Integer janesAge = jane.getAge();
 

Note that the "id" passed to BeanMapHandler can be in any case. The data type returned for id is dependent upon how your JDBC driver converts SQL column types from the Person table into Java types. The "name" and "age" columns are converted according to their property descriptors by DbUtils.

This class is thread safe.

从以下版本开始:

DbUtils 1.5

另请参阅:

ResultSetHandler

构造器概要

构造器

构造器和说明
BeanMapHandler(Class<V> type) Creates a new instance of BeanMapHandler.
BeanMapHandler(Class<V> type, int columnIndex) Creates a new instance of BeanMapHandler.
BeanMapHandler(Class<V> type, RowProcessor convert) Creates a new instance of BeanMapHandler.
BeanMapHandler(Class<V> type, String columnName) Creates a new instance of BeanMapHandler.

方法概要

限定符和类型	方法和说明
protected K	createKey(ResultSet rs) This factory method is called by handle() to retrieve the key value from the current ResultSet row.
protected V	createRow(ResultSet rs) This factory method is called by handle() to store the current ResultSet row in some object.

从类继承的方法 com.github.braisdom.objsql.jdbc.handlers.AbstractKeyedHandler

createMap, handle

从类继承的方法 java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

构造器详细资料

BeanMapHandler

public BeanMapHandler(Class<V> type)

Creates a new instance of BeanMapHandler. The value of the first column of each row will be a key in the Map.

参数:

type - The Class that objects returned from createRow() are created from.

BeanMapHandler

public BeanMapHandler(Class<V> type,
                      RowProcessor convert)

Creates a new instance of BeanMapHandler. The value of the first column of each row will be a key in the Map.

参数:

type - The Class that objects returned from createRow() are created from.

convert - The RowProcessor implementation to use when converting rows into Beans

BeanMapHandler

public BeanMapHandler(Class<V> type,
                      int columnIndex)

Creates a new instance of BeanMapHandler.

参数:

type - The Class that objects returned from createRow() are created from.

columnIndex - The values to use as keys in the Map are retrieved from the column at this index.

BeanMapHandler

public BeanMapHandler(Class<V> type,
                      String columnName)

Creates a new instance of BeanMapHandler.

参数:

type - The Class that objects returned from createRow() are created from.

columnName - The values to use as keys in the Map are retrieved from the column with this name.

方法详细资料

createKey

protected K createKey(ResultSet rs)
               throws SQLException

This factory method is called by handle() to retrieve the key value from the current ResultSet row.

指定者:

createKey 在类中 AbstractKeyedHandler<K,V>

参数:

rs - ResultSet to create a key from

返回:

K from the configured key column name/index

抛出:

SQLException - if a database access error occurs

ClassCastException - if the class datatype does not match the column type

另请参阅:

AbstractKeyedHandler.createKey(ResultSet)

createRow

protected V createRow(ResultSet rs)
               throws SQLException

从类复制的说明: AbstractKeyedHandler

This factory method is called by handle() to store the current ResultSet row in some object.

指定者:

createRow 在类中 AbstractKeyedHandler<K,V>

参数:

rs - ResultSet to create a row from

返回:

V object created from the current row

抛出:

SQLException - if a database access error occurs