org.trimou.engine.resolver

Class ReflectionResolver

java.lang.Object

org.trimou.engine.config.AbstractConfigurationAware

org.trimou.engine.resolver.AbstractResolver

org.trimou.engine.resolver.ReflectionResolver

All Implemented Interfaces:

ConfigurationAware, WithPriority, EnhancedResolver, Resolver

public class ReflectionResolver
extends AbstractResolver

Reflection-based resolver attempts to find a matching member on the context object class and its superclasses. Methods have higher priority than fields.

Author:

Martin Kouba

See Also:

Reflections#findField(Class, String), Reflections#findMethod(Class, String)

Nested Class Summary

Nested classes/interfaces inherited from interface org.trimou.engine.resolver.EnhancedResolver

EnhancedResolver.Hint

Field Summary

Fields

Modifier and Type	Field and Description
static String	COMPUTING_CACHE_CONSUMER_ID
static String	GET_PREFIX
static ConfigurationKey	HINT_FALLBACK_ENABLED_KEY Even if the runtime class of the context object changes try to apply the resolver.
static String	IS_PREFIX
static ConfigurationKey	MEMBER_CACHE_MAX_SIZE_KEY Limit the size of the cache (e.g. to avoid problems when dynamic class compilation is involved).
static int	REFLECTION_RESOLVER_PRIORITY

Fields inherited from class org.trimou.engine.config.AbstractConfigurationAware

configuration

Fields inherited from interface org.trimou.engine.resolver.Resolver

DEFAULT_PRIORITY

Constructor Summary

Constructors

Constructor and Description
ReflectionResolver()
ReflectionResolver(int priority)

Method Summary

Modifier and Type	Method and Description
EnhancedResolver.Hint	createHint(Object contextObject, String name, ResolutionContext context) This method may only be called right after the Resolver.resolve(Object, String, ResolutionContext) of the same resolver returns a non-null value.
Set<ConfigurationKey>	getConfigurationKeys()
void	init() Can be overridden so that there's no need to call super.init(Configuration).
void	invalidateMemberCache(Predicate<Class<?>> predicate) The member cache may theoretically cause memory leaks due to using hard references to Class and Member instances.
Object	resolve(Object contextObject, String name, ResolutionContext context) Resolve the value from specified context object and name.

Methods inherited from class org.trimou.engine.resolver.AbstractResolver

getPriority, toString

Methods inherited from class org.trimou.engine.config.AbstractConfigurationAware

checkNotInitialized, init

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.trimou.engine.config.ConfigurationAware

init

Field Detail

REFLECTION_RESOLVER_PRIORITY

public static final int REFLECTION_RESOLVER_PRIORITY

COMPUTING_CACHE_CONSUMER_ID

public static final String COMPUTING_CACHE_CONSUMER_ID

MEMBER_CACHE_MAX_SIZE_KEY

public static final ConfigurationKey MEMBER_CACHE_MAX_SIZE_KEY

Limit the size of the cache (e.g. to avoid problems when dynamic class compilation is involved). Use zero value to disable the cache.

HINT_FALLBACK_ENABLED_KEY

public static final ConfigurationKey HINT_FALLBACK_ENABLED_KEY

Even if the runtime class of the context object changes try to apply the resolver.

GET_PREFIX

public static final String GET_PREFIX

See Also:

Constant Field Values

IS_PREFIX

public static final String IS_PREFIX

See Also:

Constant Field Values

Constructor Detail

ReflectionResolver

public ReflectionResolver()

ReflectionResolver

public ReflectionResolver(int priority)

Method Detail

resolve

public Object resolve(Object contextObject,
                      String name,
                      ResolutionContext context)

Description copied from interface: Resolver

Resolve the value from specified context object and name. This method should return as fast as possible. The best practice is to verify params first and return null in case of the resolver is not capable of resolving it.

ResolutionContext allows to register a callback to release all the relevant resources after the resolved value is used.

Parameters:

contextObject - The current context object (aka base object), may be null

name - The name (the key or its part) is never null

context - The current resolution context

Returns:

the resolved object or null

See Also:

Placeholder.NULL

createHint

public EnhancedResolver.Hint createHint(Object contextObject,
                                        String name,
                                        ResolutionContext context)

Description copied from interface: EnhancedResolver

This method may only be called right after the Resolver.resolve(Object, String, ResolutionContext) of the same resolver returns a non-null value. The parameters must be the same.

The created hint is currently only used to skip the resolver chain for the first part of a key of a variable tag, i.e. foo for {{foo}} or {{foo.bar}}.

This method must not return null.

Specified by:

createHint in interface EnhancedResolver

Overrides:

createHint in class AbstractResolver

Returns:

the hint

See Also:

Hints.INAPPLICABLE_HINT

init

public void init()

Description copied from class: AbstractConfigurationAware

Can be overridden so that there's no need to call super.init(Configuration).

Overrides:

init in class AbstractConfigurationAware

getConfigurationKeys

public Set<ConfigurationKey> getConfigurationKeys()

Returns:

the set of configuration keys to discover

invalidateMemberCache

public void invalidateMemberCache(Predicate<Class<?>> predicate)

The member cache may theoretically cause memory leaks due to using hard references to Class and Member instances. As a temporary workaround we provide a way to invalidate the cache or some of its entries (e.g. for a concrete classloader).

Parameters:

predicate - If null, all cache entries are discarded, otherwise an entry is only discarded if the given predicate returns true for the Object.getClass()