/**
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.camel.component.bean;
import java.lang.annotation.Annotation;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.lang.reflect.Proxy;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import org.apache.camel.Attachments;
import org.apache.camel.Body;
import org.apache.camel.CamelContext;
import org.apache.camel.Exchange;
import org.apache.camel.ExchangeException;
import org.apache.camel.Expression;
import org.apache.camel.Handler;
import org.apache.camel.Header;
import org.apache.camel.Headers;
import org.apache.camel.Message;
import org.apache.camel.OutHeaders;
import org.apache.camel.Properties;
import org.apache.camel.Property;
import org.apache.camel.builder.ExpressionBuilder;
import org.apache.camel.language.LanguageAnnotation;
import org.apache.camel.spi.Registry;
import org.apache.camel.util.CastUtils;
import org.apache.camel.util.IntrospectionSupport;
import org.apache.camel.util.ObjectHelper;
import org.apache.camel.util.StringQuoteHelper;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Represents the metadata about a bean type created via a combination of
* introspection and annotations together with some useful sensible defaults
*/
public class BeanInfo {
private static final Logger LOG = LoggerFactory.getLogger(BeanInfo.class);
private static final String CGLIB_CLASS_SEPARATOR = "$$";
private static final List<Method> EXCLUDED_METHODS = new ArrayList<Method>();
private final CamelContext camelContext;
private final BeanComponent component;
private final Class<?> type;
private final ParameterMappingStrategy strategy;
private final MethodInfo defaultMethod;
// shared state with details of operations introspected from the bean, created during the constructor
private Map<String, List<MethodInfo>> operations = new HashMap<String, List<MethodInfo>>();
private List<MethodInfo> operationsWithBody = new ArrayList<MethodInfo>();
private List<MethodInfo> operationsWithNoBody = new ArrayList<MethodInfo>();
private List<MethodInfo> operationsWithCustomAnnotation = new ArrayList<MethodInfo>();
private List<MethodInfo> operationsWithHandlerAnnotation = new ArrayList<MethodInfo>();
private Map<Method, MethodInfo> methodMap = new HashMap<Method, MethodInfo>();
static {
// exclude all java.lang.Object methods as we dont want to invoke them
EXCLUDED_METHODS.addAll(Arrays.asList(Object.class.getMethods()));
// exclude all java.lang.reflect.Proxy methods as we dont want to invoke them
EXCLUDED_METHODS.addAll(Arrays.asList(Proxy.class.getMethods()));
try {
// but keep toString as this method is okay
EXCLUDED_METHODS.remove(Object.class.getMethod("toString"));
EXCLUDED_METHODS.remove(Proxy.class.getMethod("toString"));
} catch (Throwable e) {
// ignore
}
}
public BeanInfo(CamelContext camelContext, Class<?> type) {
this(camelContext, type, createParameterMappingStrategy(camelContext));
}
public BeanInfo(CamelContext camelContext, Method explicitMethod) {
this(camelContext, explicitMethod.getDeclaringClass(), explicitMethod, createParameterMappingStrategy(camelContext));
}
public BeanInfo(CamelContext camelContext, Class<?> type, ParameterMappingStrategy strategy) {
this(camelContext, type, null, strategy);
}
public BeanInfo(CamelContext camelContext, Class<?> type, Method explicitMethod, ParameterMappingStrategy strategy) {
this.camelContext = camelContext;
this.type = type;
this.strategy = strategy;
this.component = camelContext.getComponent("bean", BeanComponent.class);
final BeanInfoCacheKey key = new BeanInfoCacheKey(type, explicitMethod);
// lookup if we have a bean info cache
BeanInfo beanInfo = component.getBeanInfoFromCache(key);
if (beanInfo != null) {
// copy the values from the cache we need
defaultMethod = beanInfo.defaultMethod;
operations = beanInfo.operations;
operationsWithBody = beanInfo.operationsWithBody;
operationsWithNoBody = beanInfo.operationsWithNoBody;
operationsWithCustomAnnotation = beanInfo.operationsWithCustomAnnotation;
operationsWithHandlerAnnotation = beanInfo.operationsWithHandlerAnnotation;
methodMap = beanInfo.methodMap;
return;
}
if (explicitMethod != null) {
// must be a valid method
if (!isValidMethod(type, explicitMethod)) {
throw new IllegalArgumentException("The method " + explicitMethod + " is not valid (for example the method must be public)");
}
introspect(getType(), explicitMethod);
} else {
introspect(getType());
}
// if there are only 1 method with 1 operation then select it as a default/fallback method
MethodInfo method = null;
if (operations.size() == 1) {
List<MethodInfo> methods = operations.values().iterator().next();
if (methods.size() == 1) {
method = methods.get(0);
}
}
defaultMethod = method;
// mark the operations lists as unmodifiable, as they should not change during runtime
// to keep this code thread safe
operations = Collections.unmodifiableMap(operations);
operationsWithBody = Collections.unmodifiableList(operationsWithBody);
operationsWithNoBody = Collections.unmodifiableList(operationsWithNoBody);
operationsWithCustomAnnotation = Collections.unmodifiableList(operationsWithCustomAnnotation);
operationsWithHandlerAnnotation = Collections.unmodifiableList(operationsWithHandlerAnnotation);
methodMap = Collections.unmodifiableMap(methodMap);
// add new bean info to cache
component.addBeanInfoToCache(key, this);
}
public Class<?> getType() {
return type;
}
public CamelContext getCamelContext() {
return camelContext;
}
public static ParameterMappingStrategy createParameterMappingStrategy(CamelContext camelContext) {
// lookup in registry first if there is a user define strategy
Registry registry = camelContext.getRegistry();
ParameterMappingStrategy answer = registry.lookupByNameAndType(BeanConstants.BEAN_PARAMETER_MAPPING_STRATEGY, ParameterMappingStrategy.class);
if (answer == null) {
// no then use the default one
answer = new DefaultParameterMappingStrategy();
}
return answer;
}
public MethodInvocation createInvocation(Object pojo, Exchange exchange)
throws AmbiguousMethodCallException, MethodNotFoundException {
return createInvocation(pojo, exchange, null);
}
private MethodInvocation createInvocation(Object pojo, Exchange exchange, Method explicitMethod)
throws AmbiguousMethodCallException, MethodNotFoundException {
MethodInfo methodInfo = null;
// find the explicit method to invoke
if (explicitMethod != null) {
Iterator<List<MethodInfo>> it = operations.values().iterator();
while (it.hasNext()) {
List<MethodInfo> infos = it.next();
for (MethodInfo info : infos) {
if (explicitMethod.equals(info.getMethod())) {
return info.createMethodInvocation(pojo, exchange);
}
}
}
throw new MethodNotFoundException(exchange, pojo, explicitMethod.getName());
}
String methodName = exchange.getIn().getHeader(Exchange.BEAN_METHOD_NAME, String.class);
if (methodName != null) {
// do not use qualifier for name
String name = methodName;
if (methodName.contains("(")) {
name = ObjectHelper.before(methodName, "(");
}
boolean emptyParameters = methodName.endsWith("()");
// special for getClass, as we want the user to be able to invoke this method
// for example to log the class type or the likes
if ("class".equals(name) || "getClass".equals(name)) {
try {
Method method = pojo.getClass().getMethod("getClass");
methodInfo = new MethodInfo(exchange.getContext(), pojo.getClass(), method, Collections.<ParameterInfo>emptyList(), Collections.<ParameterInfo>emptyList(), false, false);
} catch (NoSuchMethodException e) {
throw new MethodNotFoundException(exchange, pojo, "getClass");
}
// special for length on an array type
} else if ("length".equals(name) && pojo.getClass().isArray()) {
try {
// need to use arrayLength method from ObjectHelper as Camel's bean OGNL support is method invocation based
// and not for accessing fields. And hence we need to create a MethodInfo instance with a method to call
// and therefore use arrayLength from ObjectHelper to return the array length field.
Method method = ObjectHelper.class.getMethod("arrayLength", Object[].class);
ParameterInfo pi = new ParameterInfo(0, Object[].class, null, ExpressionBuilder.mandatoryBodyExpression(Object[].class, true));
List<ParameterInfo> lpi = new ArrayList<ParameterInfo>(1);
lpi.add(pi);
methodInfo = new MethodInfo(exchange.getContext(), pojo.getClass(), method, lpi, lpi, false, false);
} catch (NoSuchMethodException e) {
throw new MethodNotFoundException(exchange, pojo, "getClass");
}
} else {
List<MethodInfo> methods = getOperations(name);
if (methods != null && methods.size() == 1) {
// only one method then choose it
methodInfo = methods.get(0);
// validate that if we want an explict no-arg method, then that's what we get
if (emptyParameters && methodInfo.hasParameters()) {
throw new MethodNotFoundException(exchange, pojo, methodName, "(with no parameters)");
}
} else if (methods != null) {
// there are more methods with that name so we cannot decide which to use
// but first let's try to choose a method and see if that complies with the name
// must use the method name which may have qualifiers
methodInfo = chooseMethod(pojo, exchange, methodName);
// validate that if we want an explicit no-arg method, then that's what we get
if (emptyParameters) {
if (methodInfo == null || methodInfo.hasParameters()) {
// we could not find a no-arg method with that name
throw new MethodNotFoundException(exchange, pojo, methodName, "(with no parameters)");
}
}
if (methodInfo == null || !name.equals(methodInfo.getMethod().getName())) {
throw new AmbiguousMethodCallException(exchange, methods);
}
} else {
// a specific method was given to invoke but not found
throw new MethodNotFoundException(exchange, pojo, methodName);
}
}
}
if (methodInfo == null) {
// no name or type
methodInfo = chooseMethod(pojo, exchange, null);
}
if (methodInfo == null) {
methodInfo = defaultMethod;
}
if (methodInfo != null) {
LOG.trace("Chosen method to invoke: {} on bean: {}", methodInfo, pojo);
return methodInfo.createMethodInvocation(pojo, exchange);
}
LOG.debug("Cannot find suitable method to invoke on bean: {}", pojo);
return null;
}
/**
* Introspects the given class
*
* @param clazz the class
*/
private void introspect(Class<?> clazz) {
// get the target clazz as it could potentially have been enhanced by CGLIB etc.
clazz = getTargetClass(clazz);
ObjectHelper.notNull(clazz, "clazz", this);
LOG.trace("Introspecting class: {}", clazz);
// if the class is not public then fallback and use interface methods if possible
// this allow Camel to invoke private beans which implements interfaces
List<Method> methods = Arrays.asList(clazz.getDeclaredMethods());
if (!Modifier.isPublic(clazz.getModifiers())) {
LOG.trace("Preferring interface methods as class: {} is not public accessible", clazz);
List<Method> interfaceMethods = getInterfaceMethods(clazz);
// still keep non-accessible class methods to provide more specific Exception if method is non-accessible
interfaceMethods.addAll(methods);
methods = interfaceMethods;
}
for (Method method : methods) {
boolean valid = isValidMethod(clazz, method);
LOG.trace("Method: {} is valid: {}", method, valid);
if (valid) {
introspect(clazz, method);
}
}
Class<?> superclass = clazz.getSuperclass();
if (superclass != null && !superclass.equals(Object.class)) {
introspect(superclass);
}
}
/**
* Introspects the given method
*
* @param clazz the class
* @param method the method
* @return the method info, is newer <tt>null</tt>
*/
private MethodInfo introspect(Class<?> clazz, Method method) {
LOG.trace("Introspecting class: {}, method: {}", clazz, method);
String opName = method.getName();
MethodInfo methodInfo = createMethodInfo(clazz, method);
// methods already registered should be preferred to use instead of super classes of existing methods
// we want to us the method from the sub class over super classes, so if we have already registered
// the method then use it (we are traversing upwards: sub (child) -> super (farther) )
MethodInfo existingMethodInfo = overridesExistingMethod(methodInfo);
if (existingMethodInfo != null) {
LOG.trace("This method is already overridden in a subclass, so the method from the sub class is preferred: {}", existingMethodInfo);
return existingMethodInfo;
}
LOG.trace("Adding operation: {} for method: {}", opName, methodInfo);
if (hasMethod(opName)) {
// we have an overloaded method so add the method info to the same key
List<MethodInfo> existing = getOperations(opName);
existing.add(methodInfo);
} else {
// its a new method we have not seen before so wrap it in a list and add it
List<MethodInfo> methods = new ArrayList<MethodInfo>();
methods.add(methodInfo);
operations.put(opName, methods);
}
if (methodInfo.hasCustomAnnotation()) {
operationsWithCustomAnnotation.add(methodInfo);
} else if (methodInfo.hasBodyParameter()) {
operationsWithBody.add(methodInfo);
} else {
operationsWithNoBody.add(methodInfo);
}
if (methodInfo.hasHandlerAnnotation()) {
operationsWithHandlerAnnotation.add(methodInfo);
}
// must add to method map last otherwise we break stuff
methodMap.put(method, methodInfo);
return methodInfo;
}
/**
* Returns the {@link MethodInfo} for the given method if it exists or null
* if there is no metadata available for the given method
*/
public MethodInfo getMethodInfo(Method method) {
MethodInfo answer = methodMap.get(method);
if (answer == null) {
// maybe the method is defined on a base class?
if (type != Object.class) {
Class<?> superclass = type.getSuperclass();
if (superclass != null && superclass != Object.class) {
BeanInfo superBeanInfo = new BeanInfo(camelContext, superclass, strategy);
return superBeanInfo.getMethodInfo(method);
}
}
}
return answer;
}
protected MethodInfo createMethodInfo(Class<?> clazz, Method method) {
Class<?>[] parameterTypes = method.getParameterTypes();
List<Annotation>[] parametersAnnotations = collectParameterAnnotations(clazz, method);
List<ParameterInfo> parameters = new ArrayList<ParameterInfo>();
List<ParameterInfo> bodyParameters = new ArrayList<ParameterInfo>();
boolean hasCustomAnnotation = false;
boolean hasHandlerAnnotation = ObjectHelper.hasAnnotation(method.getAnnotations(), Handler.class);
int size = parameterTypes.length;
if (LOG.isTraceEnabled()) {
LOG.trace("Creating MethodInfo for class: {} method: {} having {} parameters", new Object[]{clazz, method, size});
}
for (int i = 0; i < size; i++) {
Class<?> parameterType = parameterTypes[i];
Annotation[] parameterAnnotations = parametersAnnotations[i].toArray(new Annotation[parametersAnnotations[i].size()]);
Expression expression = createParameterUnmarshalExpression(clazz, method, parameterType, parameterAnnotations);
hasCustomAnnotation |= expression != null;
ParameterInfo parameterInfo = new ParameterInfo(i, parameterType, parameterAnnotations, expression);
LOG.trace("Parameter #{}: {}", i, parameterInfo);
parameters.add(parameterInfo);
if (expression == null) {
boolean bodyAnnotation = ObjectHelper.hasAnnotation(parameterAnnotations, Body.class);
LOG.trace("Parameter #{} has @Body annotation", i);
hasCustomAnnotation |= bodyAnnotation;
if (bodyParameters.isEmpty()) {
// okay we have not yet set the body parameter and we have found
// the candidate now to use as body parameter
if (Exchange.class.isAssignableFrom(parameterType)) {
// use exchange
expression = ExpressionBuilder.exchangeExpression();
} else {
// assume it's the body and it must be mandatory convertible to the parameter type
// but we allow null bodies in case the message really contains a null body
expression = ExpressionBuilder.mandatoryBodyExpression(parameterType, true);
}
LOG.trace("Parameter #{} is the body parameter using expression {}", i, expression);
parameterInfo.setExpression(expression);
bodyParameters.add(parameterInfo);
} else {
// will ignore the expression for parameter evaluation
}
}
LOG.trace("Parameter #{} has parameter info: ", i, parameterInfo);
}
// now let's add the method to the repository
return new MethodInfo(camelContext, clazz, method, parameters, bodyParameters, hasCustomAnnotation, hasHandlerAnnotation);
}
protected List<Annotation>[] collectParameterAnnotations(Class<?> c, Method m) {
@SuppressWarnings("unchecked")
List<Annotation>[] annotations = new List[m.getParameterTypes().length];
for (int i = 0; i < annotations.length; i++) {
annotations[i] = new ArrayList<Annotation>();
}
collectParameterAnnotations(c, m, annotations);
return annotations;
}
protected void collectParameterAnnotations(Class<?> c, Method m, List<Annotation>[] a) {
try {
Annotation[][] pa = c.getDeclaredMethod(m.getName(), m.getParameterTypes()).getParameterAnnotations();
for (int i = 0; i < pa.length; i++) {
a[i].addAll(Arrays.asList(pa[i]));
}
} catch (NoSuchMethodException e) {
// no method with signature of m declared on c
}
for (Class<?> i : c.getInterfaces()) {
collectParameterAnnotations(i, m, a);
}
if (!c.isInterface() && c.getSuperclass() != null) {
collectParameterAnnotations(c.getSuperclass(), m, a);
}
}
/**
* Choose one of the available methods to invoke if we can match
* the message body to the body parameter
*
* @param pojo the bean to invoke a method on
* @param exchange the message exchange
* @param name an optional name of the method that must match, use <tt>null</tt> to indicate all methods
* @return the method to invoke or null if no definitive method could be matched
* @throws AmbiguousMethodCallException is thrown if cannot choose method due to ambiguity
*/
protected MethodInfo chooseMethod(Object pojo, Exchange exchange, String name) throws AmbiguousMethodCallException {
// @Handler should be select first
// then any single method that has a custom @annotation
// or any single method that has a match parameter type that matches the Exchange payload
// and last then try to select the best among the rest
// must use defensive copy, to avoid altering the shared lists
// and we want to remove unwanted operations from these local lists
final List<MethodInfo> localOperationsWithBody = new ArrayList<MethodInfo>(operationsWithBody);
final List<MethodInfo> localOperationsWithNoBody = new ArrayList<MethodInfo>(operationsWithNoBody);
final List<MethodInfo> localOperationsWithCustomAnnotation = new ArrayList<MethodInfo>(operationsWithCustomAnnotation);
final List<MethodInfo> localOperationsWithHandlerAnnotation = new ArrayList<MethodInfo>(operationsWithHandlerAnnotation);
if (name != null) {
// filter all lists to only include methods with this name
removeNonMatchingMethods(localOperationsWithHandlerAnnotation, name);
removeNonMatchingMethods(localOperationsWithCustomAnnotation, name);
removeNonMatchingMethods(localOperationsWithBody, name);
removeNonMatchingMethods(localOperationsWithNoBody, name);
} else {
// remove all getter/setter as we do not want to consider these methods
removeAllSetterOrGetterMethods(localOperationsWithHandlerAnnotation);
removeAllSetterOrGetterMethods(localOperationsWithCustomAnnotation);
removeAllSetterOrGetterMethods(localOperationsWithBody);
removeAllSetterOrGetterMethods(localOperationsWithNoBody);
}
if (localOperationsWithHandlerAnnotation.size() > 1) {
// if we have more than 1 @Handler then its ambiguous
throw new AmbiguousMethodCallException(exchange, localOperationsWithHandlerAnnotation);
}
if (localOperationsWithHandlerAnnotation.size() == 1) {
// methods with handler should be preferred
return localOperationsWithHandlerAnnotation.get(0);
} else if (localOperationsWithCustomAnnotation.size() == 1) {
// if there is one method with an annotation then use that one
return localOperationsWithCustomAnnotation.get(0);
}
// named method and with no parameters
boolean noParameters = name != null && name.endsWith("()");
if (noParameters && localOperationsWithNoBody.size() == 1) {
// if there was a method name configured and it has no parameters, then use the method with no body (eg no parameters)
return localOperationsWithNoBody.get(0);
} else if (!noParameters && localOperationsWithBody.size() == 1 && localOperationsWithCustomAnnotation.isEmpty()) {
// if there is one method with body then use that one
return localOperationsWithBody.get(0);
}
Collection<MethodInfo> possibleOperations = new ArrayList<MethodInfo>();
possibleOperations.addAll(localOperationsWithBody);
possibleOperations.addAll(localOperationsWithCustomAnnotation);
if (!possibleOperations.isEmpty()) {
// multiple possible operations so find the best suited if possible
MethodInfo answer = chooseMethodWithMatchingBody(exchange, possibleOperations, localOperationsWithCustomAnnotation);
if (answer == null && name != null) {
// do we have hardcoded parameters values provided from the method name then fallback and try that
String parameters = ObjectHelper.between(name, "(", ")");
if (parameters != null) {
// special as we have hardcoded parameters, so we need to choose method that matches those parameters the best
answer = chooseMethodWithMatchingParameters(exchange, parameters, possibleOperations);
}
}
if (answer == null && possibleOperations.size() > 1) {
answer = getSingleCovariantMethod(possibleOperations);
}
if (answer == null) {
throw new AmbiguousMethodCallException(exchange, possibleOperations);
} else {
return answer;
}
}
// not possible to determine
return null;
}
private MethodInfo chooseMethodWithMatchingParameters(Exchange exchange, String parameters, Collection<MethodInfo> operationList)
throws AmbiguousMethodCallException {
// we have hardcoded parameters so need to match that with the given operations
Iterator<?> it = ObjectHelper.createIterator(parameters);
int count = 0;
while (it.hasNext()) {
it.next();
count++;
}
List<MethodInfo> operations = new ArrayList<MethodInfo>();
for (MethodInfo info : operationList) {
if (info.getParameters().size() == count) {
operations.add(info);
}
}
if (operations.isEmpty()) {
return null;
} else if (operations.size() == 1) {
return operations.get(0);
}
// okay we still got multiple operations, so need to match the best one
List<MethodInfo> candidates = new ArrayList<MethodInfo>();
for (MethodInfo info : operations) {
it = ObjectHelper.createIterator(parameters);
int index = 0;
boolean matches = true;
while (it.hasNext()) {
String parameter = (String) it.next();
Class<?> parameterType = BeanHelper.getValidParameterType(parameter);
Class<?> expectedType = info.getParameters().get(index).getType();
if (parameterType != null && expectedType != null) {
if (!parameterType.isAssignableFrom(expectedType)) {
matches = false;
break;
}
}
index++;
}
if (matches) {
candidates.add(info);
}
}
if (candidates.size() > 1) {
MethodInfo answer = getSingleCovariantMethod(candidates);
if (answer == null) {
throw new AmbiguousMethodCallException(exchange, candidates);
}
return answer;
}
return candidates.size() == 1 ? candidates.get(0) : null;
}
private MethodInfo getSingleCovariantMethod(Collection<MethodInfo> candidates) {
// if all the candidates are actually covariant, it doesn't matter which one we call
MethodInfo firstCandidate = candidates.iterator().next();
for (MethodInfo candidate : candidates) {
if (!firstCandidate.isCovariantWith(candidate)) {
return null;
}
}
return firstCandidate;
}
private MethodInfo chooseMethodWithMatchingBody(Exchange exchange, Collection<MethodInfo> operationList,
List<MethodInfo> operationsWithCustomAnnotation)
throws AmbiguousMethodCallException {
// see if we can find a method whose body param type matches the message body
Message in = exchange.getIn();
Object body = in.getBody();
if (body != null) {
Class<?> bodyType = body.getClass();
if (LOG.isTraceEnabled()) {
LOG.trace("Matching for method with a single parameter that matches type: {}", bodyType.getCanonicalName());
}
List<MethodInfo> possibles = new ArrayList<MethodInfo>();
List<MethodInfo> possiblesWithException = new ArrayList<MethodInfo>();
for (MethodInfo methodInfo : operationList) {
// test for MEP pattern matching
boolean out = exchange.getPattern().isOutCapable();
if (out && methodInfo.isReturnTypeVoid()) {
// skip this method as the MEP is Out so the method must return something
continue;
}
// try to match the arguments
if (methodInfo.bodyParameterMatches(bodyType)) {
LOG.trace("Found a possible method: {}", methodInfo);
if (methodInfo.hasExceptionParameter()) {
// methods with accepts exceptions
possiblesWithException.add(methodInfo);
} else {
// regular methods with no exceptions
possibles.add(methodInfo);
}
}
}
// find best suited method to use
return chooseBestPossibleMethodInfo(exchange, operationList, body, possibles, possiblesWithException, operationsWithCustomAnnotation);
}
// no match so return null
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().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;
}
/**
* Validates whether the given method is a valid candidate for Camel Bean Binding.
*
* @param clazz the class
* @param method the method
* @return true if valid, false to skip the method
*/
protected boolean isValidMethod(Class<?> clazz, Method method) {
// must not be in the excluded list
for (Method excluded : EXCLUDED_METHODS) {
if (ObjectHelper.isOverridingMethod(excluded, method)) {
// the method is overriding an excluded method so its not valid
return false;
}
}
// must be a public method
if (!Modifier.isPublic(method.getModifiers())) {
return false;
}
// return type must not be an Exchange and it should not be a bridge method
if ((method.getReturnType() != null && Exchange.class.isAssignableFrom(method.getReturnType())) || method.isBridge()) {
return false;
}
return true;
}
/**
* Does the given method info override an existing method registered before (from a subclass)
*
* @param methodInfo the method to test
* @return the already registered method to use, null if not overriding any
*/
private MethodInfo overridesExistingMethod(MethodInfo methodInfo) {
for (MethodInfo info : methodMap.values()) {
Method source = info.getMethod();
Method target = methodInfo.getMethod();
boolean override = ObjectHelper.isOverridingMethod(source, target);
if (override) {
// same name, same parameters, then its overrides an existing class
return info;
}
}
return null;
}
private MethodInfo chooseMethodWithCustomAnnotations(Exchange exchange, Collection<MethodInfo> possibles)
throws AmbiguousMethodCallException {
// if we have only one method with custom annotations let's choose that
MethodInfo chosen = null;
for (MethodInfo possible : possibles) {
if (possible.hasCustomAnnotation()) {
if (chosen != null) {
chosen = null;
break;
} else {
chosen = possible;
}
}
}
return chosen;
}
/**
* Creates an expression for the given parameter type if the parameter can
* be mapped automatically or null if the parameter cannot be mapped due to
* insufficient annotations or not fitting with the default type
* conventions.
*/
private Expression createParameterUnmarshalExpression(Class<?> clazz, Method method,
Class<?> parameterType, Annotation[] parameterAnnotation) {
// look for a parameter annotation that converts into an expression
for (Annotation annotation : parameterAnnotation) {
Expression answer = createParameterUnmarshalExpressionForAnnotation(clazz, method, parameterType, annotation);
if (answer != null) {
return answer;
}
}
// no annotations then try the default parameter mappings
return strategy.getDefaultParameterTypeExpression(parameterType);
}
private Expression createParameterUnmarshalExpressionForAnnotation(Class<?> clazz, Method method,
Class<?> parameterType, Annotation annotation) {
if (annotation instanceof Attachments) {
return ExpressionBuilder.attachmentsExpression();
} else if (annotation instanceof Property) {
Property propertyAnnotation = (Property)annotation;
return ExpressionBuilder.propertyExpression(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 static List<Method> getInterfaceMethods(Class<?> clazz) {
final List<Method> answer = new ArrayList<Method>();
for (Class<?> interfaceClazz : clazz.getInterfaces()) {
for (Method interfaceMethod : interfaceClazz.getDeclaredMethods()) {
answer.add(interfaceMethod);
}
}
return answer;
}
private static void removeAllSetterOrGetterMethods(List<MethodInfo> methods) {
Iterator<MethodInfo> it = methods.iterator();
while (it.hasNext()) {
MethodInfo info = it.next();
if (IntrospectionSupport.isGetter(info.getMethod())) {
// skip getters
it.remove();
} else if (IntrospectionSupport.isSetter(info.getMethod())) {
// skip setters
it.remove();
}
}
}
private void removeNonMatchingMethods(List<MethodInfo> methods, String name) {
Iterator<MethodInfo> it = methods.iterator();
while (it.hasNext()) {
MethodInfo info = it.next();
if (!matchMethod(info.getMethod(), name)) {
// method does not match so remove it
it.remove();
}
}
}
private boolean matchMethod(Method method, String methodName) {
if (methodName == null) {
return true;
}
if (methodName.contains("(") && !methodName.endsWith(")")) {
throw new IllegalArgumentException("Name must have both starting and ending parenthesis, was: " + methodName);
}
// do not use qualifier for name matching
String name = methodName;
if (name.contains("(")) {
name = ObjectHelper.before(name, "(");
}
// must match name
if (!name.equals(method.getName())) {
return false;
}
// is it a method with no parameters
boolean noParameters = methodName.endsWith("()");
if (noParameters) {
return method.getParameterTypes().length == 0;
}
// match qualifier types which is used to select among overloaded methods
String types = ObjectHelper.between(methodName, "(", ")");
if (ObjectHelper.isNotEmpty(types)) {
// we must qualify based on types to match method
String[] parameters = StringQuoteHelper.splitSafeQuote(types, ',');
Iterator<?> it = ObjectHelper.createIterator(parameters);
for (int i = 0; i < method.getParameterTypes().length; i++) {
if (it.hasNext()) {
Class<?> parameterType = method.getParameterTypes()[i];
String qualifyType = (String) it.next();
if (ObjectHelper.isEmpty(qualifyType)) {
continue;
}
// trim the type
qualifyType = qualifyType.trim();
if ("*".equals(qualifyType)) {
// * is a wildcard so we accept and match that parameter type
continue;
}
if (BeanHelper.isValidParameterValue(qualifyType)) {
// its a parameter value, so continue to next parameter
// as we should only check for FQN/type parameters
continue;
}
// if qualify type indeed is a class, then it must be assignable with the parameter type
Boolean assignable = BeanHelper.isAssignableToExpectedType(getCamelContext().getClassResolver(), qualifyType, parameterType);
// the method will return null if the qualifyType is not a class
if (assignable != null && !assignable) {
return false;
}
} else {
// there method has more parameters than was specified in the method name qualifiers
return false;
}
}
// if the method has no more types then we can only regard it as matched
// if there are no more qualifiers
if (it.hasNext()) {
return false;
}
}
// the method matched
return true;
}
private static Class<?> getTargetClass(Class<?> clazz) {
if (clazz != null && clazz.getName().contains(CGLIB_CLASS_SEPARATOR)) {
Class<?> superClass = clazz.getSuperclass();
if (superClass != null && !Object.class.equals(superClass)) {
return superClass;
}
}
return clazz;
}
/**
* Do we have a method with the given name.
* <p/>
* Shorthand method names for getters is supported, so you can pass in eg 'name' and Camel
* will can find the real 'getName' method instead.
*
* @param methodName the method name
* @return <tt>true</tt> if we have such a method.
*/
public boolean hasMethod(String methodName) {
return getOperations(methodName) != null;
}
/**
* Do we have a static method with the given name.
* <p/>
* Shorthand method names for getters is supported, so you can pass in eg 'name' and Camel
* will can find the real 'getName' method instead.
*
* @param methodName the method name
* @return <tt>true</tt> if we have such a static method.
*/
public boolean hasStaticMethod(String methodName) {
List<MethodInfo> methods = getOperations(methodName);
if (methods == null || methods.isEmpty()) {
return false;
}
for (MethodInfo method : methods) {
if (method.isStaticMethod()) {
return true;
}
}
return false;
}
/**
* Gets the list of methods sorted by A..Z method name.
*
* @return the methods.
*/
public List<MethodInfo> getMethods() {
if (operations.isEmpty()) {
return Collections.emptyList();
}
List<MethodInfo> methods = new ArrayList<MethodInfo>();
for (Collection<MethodInfo> col : operations.values()) {
methods.addAll(col);
}
// sort the methods by name A..Z
Collections.sort(methods, new Comparator<MethodInfo>() {
public int compare(MethodInfo o1, MethodInfo o2) {
return o1.getMethod().getName().compareTo(o2.getMethod().getName());
}
});
return methods;
}
/**
* Get the operation(s) with the given name. We can have multiple when methods is overloaded.
* <p/>
* Shorthand method names for getters is supported, so you can pass in eg 'name' and Camel
* will can find the real 'getName' method instead.
*
* @param methodName the method name
* @return the found method, or <tt>null</tt> if not found
*/
private List<MethodInfo> getOperations(String methodName) {
// do not use qualifier for name
if (methodName.contains("(")) {
methodName = ObjectHelper.before(methodName, "(");
}
List<MethodInfo> answer = operations.get(methodName);
if (answer != null) {
return answer;
}
// now try all getters to see if any of those matched the methodName
for (Method method : methodMap.keySet()) {
if (IntrospectionSupport.isGetter(method)) {
String shorthandMethodName = IntrospectionSupport.getGetterShorthandName(method);
// if the two names matches then see if we can find it using that name
if (methodName.equals(shorthandMethodName)) {
return operations.get(method.getName());
}
}
}
return null;
}
}