org.springframework.web.method.support.InvocableHandlerMethod Maven / Gradle / Ivy
/*
* Copyright 2002-2018 the original author or authors.
*
* Licensed 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.springframework.web.method.support;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.Arrays;
import org.springframework.core.DefaultParameterNameDiscoverer;
import org.springframework.core.MethodParameter;
import org.springframework.core.ParameterNameDiscoverer;
import org.springframework.lang.Nullable;
import org.springframework.util.ObjectUtils;
import org.springframework.util.ReflectionUtils;
import org.springframework.web.bind.WebDataBinder;
import org.springframework.web.bind.support.SessionStatus;
import org.springframework.web.bind.support.WebDataBinderFactory;
import org.springframework.web.context.request.NativeWebRequest;
import org.springframework.web.method.HandlerMethod;
/**
* Extension of {@link HandlerMethod} that invokes the underlying method with
* argument values resolved from the current HTTP request through a list of
* {@link HandlerMethodArgumentResolver}.
*
* @author Rossen Stoyanchev
* @author Juergen Hoeller
* @since 3.1
*/
public class InvocableHandlerMethod extends HandlerMethod {
private static final Object[] EMPTY_ARGS = new Object[0];
@Nullable
private WebDataBinderFactory dataBinderFactory;
private HandlerMethodArgumentResolverComposite resolvers = new HandlerMethodArgumentResolverComposite();
private ParameterNameDiscoverer parameterNameDiscoverer = new DefaultParameterNameDiscoverer();
/**
* Create an instance from a {@code HandlerMethod}.
*/
public InvocableHandlerMethod(HandlerMethod handlerMethod) {
super(handlerMethod);
}
/**
* Create an instance from a bean instance and a method.
*/
public InvocableHandlerMethod(Object bean, Method method) {
super(bean, method);
}
/**
* Construct a new handler method with the given bean instance, method name and parameters.
* @param bean the object bean
* @param methodName the method name
* @param parameterTypes the method parameter types
* @throws NoSuchMethodException when the method cannot be found
*/
public InvocableHandlerMethod(Object bean, String methodName, Class... parameterTypes)
throws NoSuchMethodException {
super(bean, methodName, parameterTypes);
}
/**
* Set the {@link WebDataBinderFactory} to be passed to argument resolvers allowing them to create
* a {@link WebDataBinder} for data binding and type conversion purposes.
* @param dataBinderFactory the data binder factory.
*/
public void setDataBinderFactory(WebDataBinderFactory dataBinderFactory) {
this.dataBinderFactory = dataBinderFactory;
}
/**
* Set {@link HandlerMethodArgumentResolver HandlerMethodArgumentResolvers} to use to use for resolving method argument values.
*/
public void setHandlerMethodArgumentResolvers(HandlerMethodArgumentResolverComposite argumentResolvers) {
this.resolvers = argumentResolvers;
}
/**
* Set the ParameterNameDiscoverer for resolving parameter names when needed
* (e.g. default request attribute name).
* Default is a {@link org.springframework.core.DefaultParameterNameDiscoverer}.
*/
public void setParameterNameDiscoverer(ParameterNameDiscoverer parameterNameDiscoverer) {
this.parameterNameDiscoverer = parameterNameDiscoverer;
}
/**
* Invoke the method after resolving its argument values in the context of the given request.
*
Argument values are commonly resolved through
* {@link HandlerMethodArgumentResolver HandlerMethodArgumentResolvers}.
* The {@code providedArgs} parameter however may supply argument values to be used directly,
* i.e. without argument resolution. Examples of provided argument values include a
* {@link WebDataBinder}, a {@link SessionStatus}, or a thrown exception instance.
* Provided argument values are checked before argument resolvers.
*
Delegates to {@link #getMethodArgumentValues} and calls {@link #doInvoke} with the
* resolved arguments.
* @param request the current request
* @param mavContainer the ModelAndViewContainer for this request
* @param providedArgs "given" arguments matched by type, not resolved
* @return the raw value returned by the invoked method
* @throws Exception raised if no suitable argument resolver can be found,
* or if the method raised an exception
* @see #getMethodArgumentValues
* @see #doInvoke
*/
@Nullable
public Object invokeForRequest(NativeWebRequest request, @Nullable ModelAndViewContainer mavContainer,
Object... providedArgs) throws Exception {
Object[] args = getMethodArgumentValues(request, mavContainer, providedArgs);
if (logger.isTraceEnabled()) {
logger.trace("Arguments: " + Arrays.toString(args));
}
return doInvoke(args);
}
/**
* Get the method argument values for the current request, checking the provided
* argument values and falling back to the configured argument resolvers.
*
The resulting array will be passed into {@link #doInvoke}.
* @since 5.1.2
*/
protected Object[] getMethodArgumentValues(NativeWebRequest request, @Nullable ModelAndViewContainer mavContainer,
Object... providedArgs) throws Exception {
if (ObjectUtils.isEmpty(getMethodParameters())) {
return EMPTY_ARGS;
}
MethodParameter[] parameters = getMethodParameters();
Object[] args = new Object[parameters.length];
for (int i = 0; i < parameters.length; i++) {
MethodParameter parameter = parameters[i];
parameter.initParameterNameDiscovery(this.parameterNameDiscoverer);
args[i] = findProvidedArgument(parameter, providedArgs);
if (args[i] != null) {
continue;
}
if (!this.resolvers.supportsParameter(parameter)) {
throw new IllegalStateException(formatArgumentError(parameter, "No suitable resolver"));
}
try {
args[i] = this.resolvers.resolveArgument(parameter, mavContainer, request, this.dataBinderFactory);
}
catch (Exception ex) {
// Leave stack trace for later, exception may actually be resolved and handled..
if (logger.isDebugEnabled()) {
String error = ex.getMessage();
if (error != null && !error.contains(parameter.getExecutable().toGenericString())) {
logger.debug(formatArgumentError(parameter, error));
}
}
throw ex;
}
}
return args;
}
/**
* Invoke the handler method with the given argument values.
*/
@Nullable
protected Object doInvoke(Object... args) throws Exception {
ReflectionUtils.makeAccessible(getBridgedMethod());
try {
return getBridgedMethod().invoke(getBean(), args);
}
catch (IllegalArgumentException ex) {
assertTargetBean(getBridgedMethod(), getBean(), args);
String text = (ex.getMessage() != null ? ex.getMessage() : "Illegal argument");
throw new IllegalStateException(formatInvokeError(text, args), ex);
}
catch (InvocationTargetException ex) {
// Unwrap for HandlerExceptionResolvers ...
Throwable targetException = ex.getTargetException();
if (targetException instanceof RuntimeException) {
throw (RuntimeException) targetException;
}
else if (targetException instanceof Error) {
throw (Error) targetException;
}
else if (targetException instanceof Exception) {
throw (Exception) targetException;
}
else {
throw new IllegalStateException(formatInvokeError("Invocation failure", args), targetException);
}
}
}
}