private Expression createParameterUnmarshalExpressionForAnnotation(
Class<?> clazz, Method method, Class<?> parameterType, Annotation annotation) {
if (annotation instanceof AttachmentObjects) {
return ExpressionBuilder.attachmentObjectsExpression();
} else if (annotation instanceof Attachments) {
return ExpressionBuilder.attachmentsExpression();
} else if (annotation instanceof Property) {
Property propertyAnnotation = (Property) annotation;
return ExpressionBuilder.exchangePropertyExpression(propertyAnnotation.value());
} else if (annotation instanceof ExchangeProperty) {
ExchangeProperty propertyAnnotation = (ExchangeProperty) annotation;
return ExpressionBuilder.exchangePropertyExpression(propertyAnnotation.value());
} else if (annotation instanceof Properties) {
return ExpressionBuilder.propertiesExpression();
} else if (annotation instanceof Header) {
Header headerAnnotation = (Header) annotation;
return ExpressionBuilder.headerExpression(headerAnnotation.value());
} else if (annotation instanceof Headers) {
return ExpressionBuilder.headersExpression();
} else if (annotation instanceof OutHeaders) {
return ExpressionBuilder.outHeadersExpression();
} else if (annotation instanceof ExchangeException) {
return ExpressionBuilder.exchangeExceptionExpression(
CastUtils.cast(parameterType, Exception.class));
} else {
LanguageAnnotation languageAnnotation =
annotation.annotationType().getAnnotation(LanguageAnnotation.class);
if (languageAnnotation != null) {
Class<?> type = languageAnnotation.factory();
Object object = camelContext.getInjector().newInstance(type);
if (object instanceof AnnotationExpressionFactory) {
AnnotationExpressionFactory expressionFactory = (AnnotationExpressionFactory) object;
return expressionFactory.createExpression(
camelContext, annotation, languageAnnotation, parameterType);
} else {
LOG.warn(
"Ignoring bad annotation: "
+ languageAnnotation
+ "on method: "
+ method
+ " which declares a factory: "
+ type.getName()
+ " which does not implement "
+ AnnotationExpressionFactory.class.getName());
}
}
}
return null;
}
private MethodInfo chooseBestPossibleMethodInfo(
Exchange exchange,
Collection<MethodInfo> operationList,
Object body,
List<MethodInfo> possibles,
List<MethodInfo> possiblesWithException,
List<MethodInfo> possibleWithCustomAnnotation)
throws AmbiguousMethodCallException {
Exception exception =
ExpressionBuilder.exchangeExceptionExpression().evaluate(exchange, Exception.class);
if (exception != null && possiblesWithException.size() == 1) {
LOG.trace(
"Exchange has exception set so we prefer method that also has exception as parameter");
// prefer the method that accepts exception in case we have an exception also
return possiblesWithException.get(0);
} else if (possibles.size() == 1) {
return possibles.get(0);
} else if (possibles.isEmpty()) {
LOG.trace("No possible methods so now trying to convert body to parameter types");
// let's try converting
Object newBody = null;
MethodInfo matched = null;
int matchCounter = 0;
for (MethodInfo methodInfo : operationList) {
if (methodInfo.getBodyParameterType() != null) {
if (methodInfo.getBodyParameterType().isInstance(body)) {
return methodInfo;
}
// we should only try to convert, as we are looking for best match
Object value =
exchange
.getContext()
.getTypeConverter()
.tryConvertTo(methodInfo.getBodyParameterType(), exchange, body);
if (value != null) {
if (LOG.isTraceEnabled()) {
LOG.trace(
"Converted body from: {} to: {}",
body.getClass().getCanonicalName(),
methodInfo.getBodyParameterType().getCanonicalName());
}
matchCounter++;
newBody = value;
matched = methodInfo;
}
}
}
if (matchCounter > 1) {
throw new AmbiguousMethodCallException(exchange, Arrays.asList(matched, matched));
}
if (matched != null) {
LOG.trace("Setting converted body: {}", body);
Message in = exchange.getIn();
in.setBody(newBody);
return matched;
}
} else {
// if we only have a single method with custom annotations, let's use that one
if (possibleWithCustomAnnotation.size() == 1) {
MethodInfo answer = possibleWithCustomAnnotation.get(0);
LOG.trace("There are only one method with annotations so we choose it: {}", answer);
return answer;
}
// try to choose among multiple methods with annotations
MethodInfo chosen = chooseMethodWithCustomAnnotations(exchange, possibles);
if (chosen != null) {
return chosen;
}
// just make sure the methods aren't all actually the same
chosen = getSingleCovariantMethod(possibles);
if (chosen != null) {
return chosen;
}
throw new AmbiguousMethodCallException(exchange, possibles);
}
// cannot find a good method to use
return null;
}