Details | Last modification | View Log | RSS feed
| Rev | Author | Line No. | Line |
|---|---|---|---|
| 1878 | jmachado | 1 | package com.owlike.genson; |
| 2 | |||
| 3 | import java.lang.annotation.Annotation; |
||
| 4 | import java.lang.reflect.AnnotatedElement; |
||
| 5 | |||
| 6 | import com.owlike.genson.reflect.TypeUtil; |
||
| 7 | |||
| 8 | |||
| 9 | /** |
||
| 10 | * Wrapper class must be extended by decorated converters that wrap other converters. This allows to |
||
| 11 | * access merged class information of wrapped converter and the converter itself. So instead of |
||
| 12 | * doing myObject.getClass().isAnnotationPresent(..) you will do myObject.isAnnotationPresent(..), |
||
| 13 | * where myObject is an instance of Wrapper. For example to check if a converter (or any another |
||
| 14 | * encapsulated converter and so on) has annotation @HandleNull you will do it that way: |
||
| 15 | * <p/> |
||
| 16 | * <pre> |
||
| 17 | * Wrapper.toAnnotatedElement(converter).isAnnotationPresent(HandleNull.class); |
||
| 18 | * </pre> |
||
| 19 | * <p/> |
||
| 20 | * In the future there may be other methods to access other kind of class information. |
||
| 21 | * |
||
| 22 | * @author eugen |
||
| 23 | */ |
||
| 24 | public abstract class Wrapper<T> implements 1.5.0/docs/api/java/lang/reflect/AnnotatedElement.html">AnnotatedElement { |
||
| 25 | private 1.5.0/docs/api/java/lang/reflect/AnnotatedElement.html">AnnotatedElement wrappedElement; |
||
| 26 | protected T wrapped; |
||
| 27 | |||
| 28 | protected Wrapper() { |
||
| 29 | } |
||
| 30 | |||
| 31 | protected Wrapper(T wrappedObject) { |
||
| 32 | if (wrappedObject == null) |
||
| 33 | throw new 1.5.0/docs/api/java/lang/IllegalArgumentException.html">IllegalArgumentException("Null not allowed!"); |
||
| 34 | decorate(wrappedObject); |
||
| 35 | } |
||
| 36 | |||
| 37 | public 5+0%2Fdocs%2Fapi+Annotation">Annotation[] getAnnotations() { |
||
| 38 | return Operations.union(5+0%2Fdocs%2Fapi+Annotation">Annotation[].class, wrappedElement.getAnnotations(), getClass() |
||
| 39 | .getAnnotations()); |
||
| 40 | } |
||
| 41 | |||
| 42 | public <A extends Annotation> A getAnnotation(Class<A> aClass) { |
||
| 43 | A ann = wrappedElement.getAnnotation(aClass); |
||
| 44 | return ann == null ? getClass().getAnnotation(aClass) : ann; |
||
| 45 | } |
||
| 46 | |||
| 47 | public 5+0%2Fdocs%2Fapi+Annotation">Annotation[] getDeclaredAnnotations() { |
||
| 48 | return Operations.union(5+0%2Fdocs%2Fapi+Annotation">Annotation[].class, wrappedElement.getDeclaredAnnotations(), |
||
| 49 | getClass().getDeclaredAnnotations()); |
||
| 50 | } |
||
| 51 | |||
| 52 | public boolean isAnnotationPresent(Class<? extends Annotation> annotationClass) { |
||
| 53 | return wrappedElement.isAnnotationPresent(annotationClass) |
||
| 54 | || getClass().isAnnotationPresent(annotationClass); |
||
| 55 | } |
||
| 56 | |||
| 57 | // package visibility as a convenience for CircularClassReferenceConverter |
||
| 58 | protected void decorate(T object) { |
||
| 59 | if (wrappedElement != null) |
||
| 60 | throw new 1.5.0/docs/api/java/lang/IllegalStateException.html">IllegalStateException("An object is already wrapped!"); |
||
| 61 | if (object instanceof 1.5.0/docs/api/java/lang/reflect/AnnotatedElement.html">AnnotatedElement) |
||
| 62 | this.wrappedElement = (1.5.0/docs/api/java/lang/reflect/AnnotatedElement.html">AnnotatedElement) object; |
||
| 63 | else |
||
| 64 | this.wrappedElement = object.getClass(); |
||
| 65 | this.wrapped = object; |
||
| 66 | } |
||
| 67 | |||
| 68 | public T unwrap() { |
||
| 69 | return wrapped; |
||
| 70 | } |
||
| 71 | |||
| 72 | /** |
||
| 73 | * This method acts as an adapter to AnnotatedElement, use it when you need to work on a |
||
| 74 | * converter annotations. In fact "object" argument will usually be of type converter. If this |
||
| 75 | * class is a wrapper than it will cast it to annotatedElement (as Wrapper implements |
||
| 76 | * AnnotatedElement). Otherwise we will return the class of this object. |
||
| 77 | * |
||
| 78 | * @param object may be an instance of converter for example |
||
| 79 | * @return an annotatedElement that allows us to get annotations from this object and it's |
||
| 80 | * wrapped classes if it is a Wrapper. |
||
| 81 | */ |
||
| 82 | public static 1.5.0/docs/api/java/lang/reflect/AnnotatedElement.html">AnnotatedElement toAnnotatedElement(5+0%2Fdocs%2Fapi+Object">Object object) { |
||
| 83 | if (object == null) |
||
| 84 | return null; |
||
| 85 | if (isWrapped(object)) |
||
| 86 | return (1.5.0/docs/api/java/lang/reflect/AnnotatedElement.html">AnnotatedElement) object; |
||
| 87 | else |
||
| 88 | return object.getClass(); |
||
| 89 | } |
||
| 90 | |||
| 91 | public static boolean isWrapped(5+0%2Fdocs%2Fapi+Object">Object object) { |
||
| 92 | return object instanceof Wrapper; |
||
| 93 | } |
||
| 94 | |||
| 95 | /** |
||
| 96 | * @return true if this object or its wrapped object (if the object extends Wrapper) is of type clazz. |
||
| 97 | */ |
||
| 98 | public static boolean isOfType(5+0%2Fdocs%2Fapi+Object">Object object, Class<?> clazz) { |
||
| 99 | return TypeUtil.match(object.getClass(), clazz, false) || |
||
| 100 | (isWrapped(object) && Wrapper.isOfType(((Wrapper<?>) object).unwrap(), clazz)); |
||
| 101 | } |
||
| 102 | } |