public class SqlAttributesFilter extends GenericFilter
Map
object, whose location is specified by the target
expression. If the query yields no result, then the resulting map will be empty.
The execution of the query is performed lazily; it does not occur until the first attempt
to access a value in the target. This defers the overhead of connection pool, network
and database query processing until a value is first required. This also means that the
parameters
expressions will not be evaluated until the map is first accessed.
PreparedStatement
Modifier and Type | Class and Description |
---|---|
static class |
SqlAttributesFilter.Heaplet
Creates and initializes a static attribute provider in a heap environment.
|
logger, storage
Constructor and Description |
---|
SqlAttributesFilter(DataSource dataSource,
Expression target,
String preparedStatement)
Builds a new SqlAttributesFilter that will execute the given SQL statement on the given
DataSource ,
placing the results in a Map in the specified target. |
Modifier and Type | Method and Description |
---|---|
void |
filter(Exchange exchange,
Handler next)
Filters the request and/or response of an exchange.
|
List<Expression> |
getParameters()
Returns the list of parameters to evaluate and include in the execution of the prepared statement.
|
public SqlAttributesFilter(DataSource dataSource, Expression target, String preparedStatement)
DataSource
,
placing the results in a Map
in the specified target.dataSource
- JDBC data sourcetarget
- Expression that yields the target object that will contain the mapped resultspreparedStatement
- The parametrized SQL query to execute, with ? parameter placeholderspublic List<Expression> getParameters()
public void filter(Exchange exchange, Handler next) throws HandlerException, IOException
Filter
exchange.request
contains the request to be filtered. To pass the request to the next filter or handler
in the chain, the filter calls next.handle(exchange)
. After this call,
exchange.response
contains the response that can be filtered.
This method may elect not to pass the request to the next filter or handler, and instead
handle the request itself. It can achieve this by merely avoiding a call to
next.handle(exchange)
and creating its own response object the exchange. The
filter is also at liberty to replace a response with another of its own after the call
to next.handle(exchange)
.
Important note: If an existing response exists in the exchange object
and the filter intends to replace it with its own, it must first check to see if the
existing response has an entity, and if it does, must call its close
method in
order to signal that the processing of the response from a remote server is complete.
exchange
- the exchange containing the request and response to filter.next
- the next filter or handler in the chain to handle the exchange.HandlerException
- if an exception occurred handling the exchange.IOException
- if an I/O exception occurred.Copyright © 2014 ForgeRock AS. All rights reserved.