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package com.airbnb.epoxy;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
/**
* Used to annotate fields on EpoxyModel classes in order to generate a subclass of that model with
* getters, setters, equals, and hashcode for the annotated fields.
*/
@Target(ElementType.FIELD)
@Retention(RetentionPolicy.CLASS)
public @interface EpoxyAttribute {
/**
* Options that can be included on the attribute to affect how the model's generated class is
* created.
*/
enum Option {
/**
* A getter is generated for this attribute by default. Add this option to prevent a getter from
* being generated.
*/
NoGetter,
/**
* A setter is generated for this attribute by default. Add this option to prevent a setter from
* being generated.
*/
NoSetter,
/**
* By default every attribute's hashCode and equals method is called when determining the
* model's state. This option can be used to exclude an attribute's hashCode/equals from
* contributing to the state.
*
* This is useful for objects that may change without actually changing the model's state. A
* common case is an anonymous click listener that gets recreated with every bind call.
*
* When this is used, the attribute will affect the model state solely based on whether it is
* null or non null.
*
* A good rule of thumb for whether to use this on an attribute is, "If this is the only
* attribute that changed do I still need to rebind and update the view?" If the answer if no
* then you can use this to prevent the rebind.
*/
DoNotHash,
/**
* This is meant to be used in conjunction with {@link PackageEpoxyConfig#requireHashCode()}.
* When that is enabled every attribute must implement hashCode/equals. However, there are some
* valid cases where the attribute type does not implement hashCode/equals, but it should still
* be hashed at runtime and contribute to the model's state. Use this option on an attribute in
* that case to tell the processor to let it pass the hashCode/equals validation.
*
* An example case is AutoValue classes, where the generated class correctly implements
* hashCode/equals at runtime.
*
* If you use this it is your responsibility to ensure that the object assigned to the attribute
* at runtime correctly implements hashCode/equals. If you don't want the attribute to
* contribute to model state you should use {@link Option#DoNotHash} instead.
*/
IgnoreRequireHashCode,
/**
* This attribute is used in {@link Object#toString()} implementation by default.
* Add this option to prevent this attribute being used in {@link Object#toString()}.
*/
DoNotUseInToString
}
/** Specify any {@link Option} values that should be used when generating the model class. */
Option[] value() default {};
/**
* Whether or not to include this attribute in equals and hashCode calculations.
*
* It may be useful to disable this for objects that get recreated without the underlying data
* changing such as a click listener that gets created inline in every bind call.
*
* @deprecated Use {@link Option#DoNotHash} instead.
*/
@Deprecated
boolean hash() default true;
/**
* Whether or not to generate setter for this attribute.
*
* It may be useful to disable this for attribute which can be immutable and doesn't require
* setter.
*
* @deprecated Use {@link Option#NoSetter} instead.
*/
@Deprecated
boolean setter() default true;
}