Package org.apache.commons.jexl3.internal.introspection

Class DuckGetExecutor

java.lang.Object

org.apache.commons.jexl3.internal.introspection.AbstractExecutor

org.apache.commons.jexl3.internal.introspection.AbstractExecutor.Get

org.apache.commons.jexl3.internal.introspection.DuckGetExecutor

All Implemented Interfaces:

JexlPropertyGet

public final class DuckGetExecutor
extends AbstractExecutor.Get

Specialized executor to get a property from an object.

Duck as in duck-typing for an interface like: interface Get { Object get(Object key); }

Since:

2.0

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.commons.jexl3.internal.introspection.AbstractExecutor

AbstractExecutor.Get, AbstractExecutor.Method, AbstractExecutor.Set

Field Summary

Fields

Modifier and Type	Field	Description
private final Object	property	The property, may be null.

Fields inherited from class org.apache.commons.jexl3.internal.introspection.AbstractExecutor

method, objectClass, TRY_FAILED

Constructor Summary

Constructors

Modifier	Constructor	Description
private	DuckGetExecutor(Class<?> clazz, Method method, Object identifier)	Creates an instance.

Method Summary

Modifier and Type	Method	Description
static DuckGetExecutor	discover(Introspector is, Class<?> clazz, Object identifier)	Attempts to discover a DuckGetExecutor.
Object	getTargetProperty()	Gets the property targeted by this executor.
Object	invoke(Object obj)	Method used to get the property value of an object.
Object	tryInvoke(Object obj, Object key)	Attempts to reuse this JexlPropertyGet, checking that it is compatible with the actual set of arguments.

Methods inherited from class org.apache.commons.jexl3.internal.introspection.AbstractExecutor

castInteger, castString, classOf, equals, equals, getMethod, getMethodName, getTargetClass, hashCode, initMarker, isAlive, isCacheable, makeArgs, tryFailed

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.commons.jexl3.introspection.JexlPropertyGet

isCacheable, tryFailed

Field Details

property

private final Object property

The property, may be null.

Constructor Details

DuckGetExecutor

private DuckGetExecutor(Class<?> clazz,
 Method method,
 Object identifier)

Creates an instance.

Parameters:

clazz - he class the get method applies to

method - the method held by this executor

identifier - the property to get

Method Details

discover

public static DuckGetExecutor discover(Introspector is,
 Class<?> clazz,
 Object identifier)

Attempts to discover a DuckGetExecutor.

Parameters:

is - the introspector

clazz - the class to find the get method from

identifier - the key to use as an argument to the get method

Returns:

the executor if found, null otherwise

getTargetProperty

public Object getTargetProperty()

Description copied from class: AbstractExecutor

Gets the property targeted by this executor.

Overrides:

getTargetProperty in class AbstractExecutor

Returns:

the target property

invoke

public Object invoke(Object obj)
              throws IllegalAccessException,
InvocationTargetException

Description copied from interface: JexlPropertyGet

Method used to get the property value of an object.

Parameters:

obj - the object to get the property value from.

Returns:

the property value.

Throws:

IllegalAccessException

InvocationTargetException

tryInvoke

public Object tryInvoke(Object obj,
 Object key)

Description copied from interface: JexlPropertyGet

Attempts to reuse this JexlPropertyGet, checking that it is compatible with the actual set of arguments.

Parameters:

obj - the object to invoke the property get upon

key - the property key to get

Returns:

the result of the method invocation that should be checked by tryFailed to determine if it succeeded or failed.