Jaxb2CollectionHttpMessageConverter.java 文件源码

/**
 * {@inheritDoc}
 * <p>Jaxb2CollectionHttpMessageConverter can read a generic
 * {@link Collection} where the generic type is a JAXB type annotated with
 * {@link XmlRootElement} or {@link XmlType}.
 */
@Override
public boolean canRead(Type type, Class<?> contextClass, MediaType mediaType) {
    if (!(type instanceof ParameterizedType)) {
        return false;
    }
    ParameterizedType parameterizedType = (ParameterizedType) type;
    if (!(parameterizedType.getRawType() instanceof Class)) {
        return false;
    }
    Class<?> rawType = (Class<?>) parameterizedType.getRawType();
    if (!(Collection.class.isAssignableFrom(rawType))) {
        return false;
    }
    if (parameterizedType.getActualTypeArguments().length != 1) {
        return false;
    }
    Type typeArgument = parameterizedType.getActualTypeArguments()[0];
    if (!(typeArgument instanceof Class)) {
        return false;
    }
    Class<?> typeArgumentClass = (Class<?>) typeArgument;
    return (typeArgumentClass.isAnnotationPresent(XmlRootElement.class) ||
            typeArgumentClass.isAnnotationPresent(XmlType.class)) && canRead(mediaType);
}