de.japkit.metaannotations.Field Maven / Gradle / Ivy
package de.japkit.metaannotations;
import java.lang.annotation.ElementType;
import java.lang.annotation.Target;
import javax.lang.model.element.ElementKind;
import javax.lang.model.element.Modifier;
import de.japkit.metaannotations.classselectors.None;
/**
* Anntoation to add a field to a generated class.
*
* @author stefan
*
*/
@Target(ElementType.FIELD)
public @interface Field {
/**
* When the annotated annotation wants to override annotation values of the
* Method annotation, it must use this prefix.
*
* @return
*/
String _prefix() default "";
/**
* An expression to determine the source object for generating this element.
* The source element is available as "src" in expressions and is used in
* matchers and other rules. If the src expression is not set, the src
* element of the parent element is used (usually the enclosing element).
*
* If this expression results in an Iterable, each object provided by the
* Iterator is use as source object. That is, the element is generated
* multiple times, once for each object given by the iterator.
*
* @return
*/
String src() default "";
/**
* As an alternative to the src expression, a function can be called to determine the source object.
*
* @return
*/
Class[] srcFun() default {};
/**
* A filter expression to be applied to src in case it is a collection. Must be boolean.
* The variable name for the current collection element to be filtered is "src".
* @return
*/
String srcFilter() default "";
/**
* As an alternative to srcFilter, one or more boolean functions can be called.
* Only if the conjunction of their results is true, the rule is applied for the considered element of the src collection.
*
* @return
*/
Class[] srcFilterFun() default {};
/**
* An expression to be applied to the result of the expression or function(s) in case it is a collection. It's applied to each element.
* The variable name for the current collection element is "src". Collect is applied after filtering.
*
* @return
*/
String srcCollect() default "";
/**
* As an alternative or additionally to the collect expression, one or more functions can be called.
* In case of more than one function, they are called in a "fluent" style. That is each one is applied to the result of the previous one.
* The first function is always applied to the result of the collect expression or to the current collection element if collect expression is empty.
*
* @return
*/
Class[] srcCollectFun() default {};
/**
* If true, and src is a collection, it is transformed to a LinkedHashSet to remove duplicates while preserving order.
*
* @return
*/
boolean srcToSet() default false;
/**
* If src is a collection, and srcGroupBy and / or srcGroupByFun are set, the collection elements are grouped as a map, where
* the keys are the results of applying srcGroupBy and / or srcGroupByFun to the collection elements and the values are lists
* of collection elements with same key. SrcGroupBy is an expression and srcGroupByFun is a list of functions.
* They are applied in a fluent style (like src.srcGroupBy().srcGroupByFun[0]().srcGroupByFun[1]()...).
*
* @return the expression to derive the key from a collection element. The collection element is provided as "src".
*/
String srcGroupBy() default "";
/**
* If src is a collection, and srcGroupBy and / or srcGroupByFun are set, the collection elements are grouped as a map, where
* the keys are the results of applying srcGroupBy and / or srcGroupByFun to the collection elements and the values are lists
* of collection elements with same key. SrcGroupBy is an expression and srcGroupByFun is a list of functions.
* They are applied in a fluent style (like src.srcGroupBy().srcGroupByFun[0]().srcGroupByFun[1]()...).
*
* @return function(s) to derive the key from a collection element. The collection element is provided as "src".
*/
Class[] srcGroupByFun() default {};
/**
*
* @return the language of the src expression. Defaults to Java EL.
*/
String srcLang() default "";
/**
* By default, the current source object has the name "src" on the value stack.
* If this annotation value is set, the source object will additionally provided under the given name.
*
* @return the name of the source variable
*/
String srcVar() default "";
/**
* EL Variables within the scope of the field.
*
* @return
*/
Var[] vars() default {};
/**
* By default, this rule is active.
* To switch it on or of case by case, a boolean expression can be used here.
*
* @return
*/
String cond() default "";
/**
* The expression language for the cond expression.
* @return
*/
String condLang() default "";
/**
* As an alternative to the cond expression, a boolean function can be called.
*
* @return
*/
Class[] condFun() default {};
/**
*
* @return the name of the method. If not empty, nameExpr is ignored.
*/
String name() default "";
/**
* For more complex cases: a Java EL expression to generate the name of the
* field.
*
* @return
*/
String nameExpr() default "";
/**
*
* @return the language of the name expression. Defaults to Java EL.
*/
String nameLang() default "";
/**
*
* @return the type of the field.
*/
Class type() default None.class;
Class[] typeArgs() default {};
/**
*
* @return the modifiers of the field
*/
Modifier[] modifiers() default {};
/**
* How to map annotations of the source element (???) to the field
*
*
* @return the annotation mappings
*/
Annotation[] annotations() default {};
/**
* Classes to be imported for the initializer. Allows to use short class
* names in the expr. The imports are only added if they don't conflict with
* others. Otherwise, it's an error. TODO: Instead of an error , we could
* replace the short name in the body by the fqn.
*
* @return
*/
Class[] imports() default {};
/**
* If the init expression shall contain some repetitive code, this
* expression can be used. It determines how often to repeat initExpr. The
* iteration variable is provided as "src" on the value stack (and thus
* hides the source object given by the src annotation value).
*
* A typical example is to initialize some array with the names of the
* properties of the class.
*
*
* @return
*/
String initIterator() default "";
/**
*
* @return the language of the init iterator expression. Default is Java EL.
*/
String initIteratorLang() default "";
/**
*
* @return if inityIterator is set, this code is inserted between each
* iteration of initExpr.
*/
String initSeparator() default "";
/**
* If true, a linebreak is inserted after the "before expression", the "init expression" and the "after expression".
* @return
*/
boolean initLinebreak() default false;
/**
*
* @return an expression for the code to be generated before the repetitive
* initCode. Only rendered, if the iterator expression is set and
* does not result in an empty iterator.
*/
String initBeforeIteratorCode() default "";
/**
*
* @return an expression for the code to be generated after the repetitive
* initCode. Only rendered, if the iterator expression is set and
* does not result in an empty iterator.
*/
String initAfterIteratorCode() default "";
/**
*
* @return an expression for the code to be generated if the iterator
* expression is set but does result in an empty iterator.
*/
String initEmptyIteratorCode() default "";
/**
*
* @return a Java EL expression to generate the initializer. The root
* property "src" refers to the generated field or to the iterator variable.
*/
String initCode() default "";
/**
* If there is at least one of the given cases, where all matcher match, the according expression is use instead of initExpr.
* If no case matches, the default is initExpr.
*
* @return
*/
Case[] initCases() default{};
/**
*
* @return the language of the init expression. Default is Java EL.
*/
String initLang() default "";
/**
* The delegate methods to create. The delegate is the generated field.
*
* @return
*/
DelegateMethods[] delegateMethods() default {};
/**
*
* @return true means to copy the JavaDoc comment from the rule source element
*/
boolean commentFromSrc() default false;
/**
*
* @return an expression to create the JavaDoc comment
*/
String commentExpr() default "";
/**
*
* @return the expression language for commentExpr
*/
String commentLang() default "";
/**
* If dependent members are created, the generated field by default becomes the src element for the according rules.
* If the original src shall be used instead, set this AV to false.
* @return
*/
boolean genElementIsSrcForDependentRules() default true;
/**
* A Setter annotation here means to generate a setter for the field. The
* annotation can be used to further customize the setter, but all values
* are optional.
*
* @return the setter annotation
*/
Setter[] setter() default {};
/**
* A Getter annotation here means to generate a getter for the field. The
* annotation can be used to further customize the getter, but all values
* are optional.
*
* @return the setter annotation
*/
Getter[] getter() default {};
/**
* A class to customize the generated fields. So far, you can override the annotations of the field or add new annotations.
*
* TODO: Remove annotations? f.e. @Not({NotNull.class, ...})
* Enforce Field order?
* Complex annotation mapping modes?
*
* @return
*/
Class manualOverrides() default None.class;
/**
* By default, all fields of the "overrides" class are considered. This can
* be changed by setting another matcher here. For example, only fields with
* some specific annotation could be considered. Or, methods could be
* considered that are named like the properties.
*
* @return
*/
Matcher manualOverridesMatcher() default @Matcher(kind = ElementKind.FIELD);
}