com.espertech.esper.event.bean

Class DynamicPropertyGetterBase

java.lang.Object

com.espertech.esper.event.bean.DynamicPropertyGetterBase

All Implemented Interfaces:

EventPropertyGetter, BeanEventPropertyGetter, EventPropertyGetterSPI

Direct Known Subclasses:

DynamicIndexedPropertyGetter, DynamicMappedPropertyGetter, DynamicSimplePropertyGetter

public abstract class DynamicPropertyGetterBase
extends Object
implements BeanEventPropertyGetter

Base class for getters for a dynamic property (syntax field.inner?), caches methods to use for classes.

Constructor Summary

Constructors

Constructor and Description
DynamicPropertyGetterBase(EventAdapterService eventAdapterService)

Method Summary

Modifier and Type	Method and Description
static Object	cacheAndCall(CopyOnWriteArrayList<DynamicPropertyDescriptor> cache, DynamicPropertyGetterBase getter, Object object, EventAdapterService eventAdapterService) NOTE: Code-generation-invoked method, method name and parameter order matters
static boolean	cacheAndExists(CopyOnWriteArrayList<DynamicPropertyDescriptor> cache, DynamicPropertyGetterBase getter, Object object, EventAdapterService eventAdapterService) NOTE: Code-generation-invoked method, method name and parameter order matters
protected abstract Object	call(DynamicPropertyDescriptor descriptor, Object underlying) Call the getter to obtains the return result object, or null if no such method exists.
CodegenExpression	codegenEventBeanExists(CodegenExpression beanExpression, CodegenContext context)
CodegenExpression	codegenEventBeanFragment(CodegenExpression beanExpression, CodegenContext context)
CodegenExpression	codegenEventBeanGet(CodegenExpression beanExpression, CodegenContext context)
CodegenExpression	codegenUnderlyingExists(CodegenExpression underlyingExpression, CodegenContext context)
CodegenExpression	codegenUnderlyingFragment(CodegenExpression underlyingExpression, CodegenContext context)
CodegenExpression	codegenUnderlyingGet(CodegenExpression underlyingExpression, CodegenContext context)
protected abstract Method	determineMethod(Class clazz) To be implemented to return the method required, or null to indicate an appropriate method could not be found.
Object	get(EventBean event) Return the value for the property in the event object specified when the instance was obtained.
Object	getBeanProp(Object object) Returns the property as an object.
Class	getBeanPropType()
Object	getFragment(EventBean eventBean) Returns EventBean or array of EventBean for a property name or property expression.
Class	getTargetType()
boolean	isBeanExistsProperty(Object object) Returns true if the dynamic property exists.
boolean	isExistsProperty(EventBean eventBean) Returns true if the property exists, or false if the type does not have such a property.

Methods inherited from class java.lang.Object

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

Constructor Detail

DynamicPropertyGetterBase

public DynamicPropertyGetterBase(EventAdapterService eventAdapterService)

Method Detail

determineMethod

protected abstract Method determineMethod(Class clazz)

To be implemented to return the method required, or null to indicate an appropriate method could not be found.

Parameters:

clazz - to search for a matching method

Returns:

method if found, or null if no matching method exists

call

protected abstract Object call(DynamicPropertyDescriptor descriptor,
                               Object underlying)

Call the getter to obtains the return result object, or null if no such method exists.

Parameters:

descriptor - provides method information for the class

underlying - is the underlying object to ask for the property value

Returns:

underlying

cacheAndCall

public static Object cacheAndCall(CopyOnWriteArrayList<DynamicPropertyDescriptor> cache,
                                  DynamicPropertyGetterBase getter,
                                  Object object,
                                  EventAdapterService eventAdapterService)

NOTE: Code-generation-invoked method, method name and parameter order matters

Parameters:

cache - cache

getter - getter

object - object

eventAdapterService - event server

Returns:

property

cacheAndExists

public static boolean cacheAndExists(CopyOnWriteArrayList<DynamicPropertyDescriptor> cache,
                                     DynamicPropertyGetterBase getter,
                                     Object object,
                                     EventAdapterService eventAdapterService)

NOTE: Code-generation-invoked method, method name and parameter order matters

Parameters:

cache - cache

getter - getter

object - object

eventAdapterService - event server

Returns:

exists-flag

getBeanProp

public Object getBeanProp(Object object)
                   throws PropertyAccessException

Description copied from interface: BeanEventPropertyGetter

Returns the property as an object.

Specified by:

getBeanProp in interface BeanEventPropertyGetter

Parameters:

object - to evaluate

Returns:

property of object

Throws:

PropertyAccessException - if access failed

getTargetType

public Class getTargetType()

Specified by:

getTargetType in interface BeanEventPropertyGetter

isBeanExistsProperty

public boolean isBeanExistsProperty(Object object)

Description copied from interface: BeanEventPropertyGetter

Returns true if the dynamic property exists.

Specified by:

isBeanExistsProperty in interface BeanEventPropertyGetter

Parameters:

object - to evaluate

Returns:

indicator if property exists

get

public final Object get(EventBean event)
                 throws PropertyAccessException

Description copied from interface: EventPropertyGetter

Return the value for the property in the event object specified when the instance was obtained. Useful for fast access to event properties. Throws a PropertyAccessException if the getter instance doesn't match the EventType it was obtained from, and to indicate other property access problems.

Specified by:

get in interface EventPropertyGetter

Parameters:

event - is the event to get the value of a property from

Returns:

value of property in event

Throws:

PropertyAccessException - to indicate that property access failed

isExistsProperty

public boolean isExistsProperty(EventBean eventBean)

Description copied from interface: EventPropertyGetter

Returns true if the property exists, or false if the type does not have such a property.

Useful for dynamic properties of the syntax "property?" and the dynamic nested/indexed/mapped versions. Dynamic nested properties follow the syntax "property?.nested" which is equivalent to "property?.nested?". If any of the properties in the path of a dynamic nested property return null, the dynamic nested property does not exists and the method returns false.

For non-dynamic properties, this method always returns true since a getter would not be available unless

Specified by:

isExistsProperty in interface EventPropertyGetter

Parameters:

eventBean - is the event to check if the dynamic property exists

Returns:

indictor whether the property exists, always true for non-dynamic (default) properties

getBeanPropType

public Class getBeanPropType()

Specified by:

getBeanPropType in interface BeanEventPropertyGetter

codegenEventBeanGet

public CodegenExpression codegenEventBeanGet(CodegenExpression beanExpression,
                                             CodegenContext context)

Specified by:

codegenEventBeanGet in interface EventPropertyGetterSPI

codegenEventBeanExists

public CodegenExpression codegenEventBeanExists(CodegenExpression beanExpression,
                                                CodegenContext context)

Specified by:

codegenEventBeanExists in interface EventPropertyGetterSPI

codegenEventBeanFragment

public CodegenExpression codegenEventBeanFragment(CodegenExpression beanExpression,
                                                  CodegenContext context)

Specified by:

codegenEventBeanFragment in interface EventPropertyGetterSPI

codegenUnderlyingGet

public CodegenExpression codegenUnderlyingGet(CodegenExpression underlyingExpression,
                                              CodegenContext context)

Specified by:

codegenUnderlyingGet in interface EventPropertyGetterSPI

codegenUnderlyingExists

public CodegenExpression codegenUnderlyingExists(CodegenExpression underlyingExpression,
                                                 CodegenContext context)

Specified by:

codegenUnderlyingExists in interface EventPropertyGetterSPI

codegenUnderlyingFragment

public CodegenExpression codegenUnderlyingFragment(CodegenExpression underlyingExpression,
                                                   CodegenContext context)

Specified by:

codegenUnderlyingFragment in interface EventPropertyGetterSPI

getFragment

public Object getFragment(EventBean eventBean)

Description copied from interface: EventPropertyGetter

Returns EventBean or array of EventBean for a property name or property expression.

For use with properties whose value is itself an event or whose value can be represented as an event by the underlying event representation.

The EventType of the EventBean instance(s) returned by this method can be determined by EventType.getFragmentType(String). Use EventPropertyDescriptor to obtain a list of properties that return fragments from an event type.

Returns null if the property value is null or the property value cannot be represented as a fragment by the underlying representation.

Specified by:

getFragment in interface EventPropertyGetter

Parameters:

eventBean - is the event to get the fragment value of a property

Returns:

the value of a property as an EventBean or array of EventBean