我解决了这个问题。
客户端:
我正在使用这个库https://github.com/ggeorgovassilis/spring-rest-invoker/。这个库可以从接口生成代理来调用Spring Rest服务。
我扩展了这个库:
我创建了一个注释和一个工厂客户端类:
识别Spring Rest服务
@Target({ElementType.TYPE})
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface SpringRestService {
String baseUri();
}
这个类从接口生成客户端rest
public class RestFactory implements BeanFactoryPostProcessor,EmbeddedValueResolverAware {
StringValueResolver resolver;
@Override
public void setEmbeddedValueResolver(StringValueResolver resolver) {
this.resolver = resolver;
}
private String basePackage = "com";
public void setBasePackage(String basePackage) {
this.basePackage = basePackage;
}
@Override
public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException {
createBeanProxy(beanFactory,SpringRestService.class);
createBeanProxy(beanFactory,JaxrsRestService.class);
}
private void createBeanProxy(ConfigurableListableBeanFactory beanFactory,Class<? extends Annotation> annotation) {
List<Class<Object>> classes;
try {
classes = AnnotationUtils.findAnnotatedClasses(basePackage, annotation);
} catch (Exception e) {
throw new BeanInstantiationException(annotation, e.getMessage(), e);
}
BeanDefinitionRegistry registry = (BeanDefinitionRegistry) beanFactory;
for (Class<Object> classType : classes) {
Annotation typeService = classType.getAnnotation(annotation);
GenericBeanDefinition beanDef = new GenericBeanDefinition();
beanDef.setBeanClass(getQueryServiceFactory(classType, typeService));
ConstructorArgumentValues cav = new ConstructorArgumentValues();
cav.addIndexedArgumentValue(0, classType);
cav.addIndexedArgumentValue(1, baseUri(classType,typeService));
beanDef.setConstructorArgumentValues(cav);
registry.registerBeanDefinition(classType.getName() + "Proxy", beanDef);
}
}
private String baseUri(Class<Object> c,Annotation typeService){
String baseUri = null;
if(typeService instanceof SpringRestService){
baseUri = ((SpringRestService)typeService).baseUri();
}else if(typeService instanceof JaxrsRestService){
baseUri = ((JaxrsRestService)typeService).baseUri();
}
if(baseUri!=null && !baseUri.isEmpty()){
return baseUri = resolver.resolveStringValue(baseUri);
}else{
throw new IllegalStateException("Impossibile individuare una baseUri per l'interface :"+c);
}
}
private static Class<? extends FactoryBean<?>> getQueryServiceFactory(Class<Object> c,Annotation typeService){
if(typeService instanceof SpringRestService){
return it.eng.rete2i.springjsonmapper.spring.SpringRestInvokerProxyFactoryBean.class;
}else if(typeService instanceof JaxrsRestService){
return it.eng.rete2i.springjsonmapper.jaxrs.JaxRsInvokerProxyFactoryBean.class;
}
throw new IllegalStateException("Impossibile individuare una classe per l'interface :"+c);
}
}
我配置我的工厂:
<bean class="it.eng.rete2i.springjsonmapper.factory.RestFactory">
<property name="basePackage" value="it.giancarlo.rest.services" />
</bean>
关于REST服务签名
这是一个示例接口:
package it.giancarlo.rest.services.spring;
import ...
@SpringRestService(baseUri="${bookservice.url}")
public interface BookService{
@Override
@RequestMapping("/volumes")
QueryResult findBooksByTitle(@RequestParam("q") String q);
@Override
@RequestMapping("/volumes/{id}")
Item findBookById(@PathVariable("id") String id);
}
关于REST服务实现
服务实现
@RestController
@RequestMapping("bookService")
public class BookServiceImpl implements BookService {
@Override
public QueryResult findBooksByTitle(String q) {
return null;
}
@Override
public Item findBookById(String id) {
return null;
}
}
为了解决参数注释问题,我创建了一个自定义的RequestMappingHandlerMapping,它查找所有使用@SpringRestService注释的接口。
public class RestServiceRequestMappingHandlerMapping extends RequestMappingHandlerMapping{
public HandlerMethod testCreateHandlerMethod(Object handler, Method method){
return createHandlerMethod(handler, method);
}
@Override
protected HandlerMethod createHandlerMethod(Object handler, Method method) {
HandlerMethod handlerMethod;
if (handler instanceof String) {
String beanName = (String) handler;
handlerMethod = new RestServiceHandlerMethod(beanName,getApplicationContext().getAutowireCapableBeanFactory(), method);
}
else {
handlerMethod = new RestServiceHandlerMethod(handler, method);
}
return handlerMethod;
}
public static class RestServiceHandlerMethod extends HandlerMethod{
private Method interfaceMethod;
public RestServiceHandlerMethod(Object bean, Method method) {
super(bean,method);
changeType();
}
public RestServiceHandlerMethod(Object bean, String methodName, Class<?>... parameterTypes) throws NoSuchMethodException {
super(bean,methodName,parameterTypes);
changeType();
}
public RestServiceHandlerMethod(String beanName, BeanFactory beanFactory, Method method) {
super(beanName,beanFactory,method);
changeType();
}
private void changeType(){
for(Class<?> clazz : getMethod().getDeclaringClass().getInterfaces()){
if(clazz.isAnnotationPresent(SpringRestService.class)){
try{
interfaceMethod = clazz.getMethod(getMethod().getName(), getMethod().getParameterTypes());
break;
}catch(NoSuchMethodException e){
}
}
}
MethodParameter[] params = super.getMethodParameters();
for(int i=0;i<params.length;i++){
params[i] = new RestServiceMethodParameter(params[i]);
}
}
private class RestServiceMethodParameter extends MethodParameter{
private volatile Annotation[] parameterAnnotations;
public RestServiceMethodParameter(MethodParameter methodParameter){
super(methodParameter);
}
@Override
public Annotation[] getParameterAnnotations() {
if (this.parameterAnnotations == null){
if(RestServiceHandlerMethod.this.interfaceMethod!=null) {
Annotation[][] annotationArray = RestServiceHandlerMethod.this.interfaceMethod.getParameterAnnotations();
if (this.getParameterIndex() >= 0 && this.getParameterIndex() < annotationArray.length) {
this.parameterAnnotations = annotationArray[this.getParameterIndex()];
}
else {
this.parameterAnnotations = new Annotation[0];
}
}else{
this.parameterAnnotations = super.getParameterAnnotations();
}
}
return this.parameterAnnotations;
}
}
}
}
我创建了一个配置类
@Configuration
public class WebConfig extends WebMvcConfigurationSupport{
@Bean
public RequestMappingHandlerMapping requestMappingHandlerMapping() {
RestServiceRequestMappingHandlerMapping handlerMapping = new RestServiceRequestMappingHandlerMapping();
handlerMapping.setOrder(0);
handlerMapping.setInterceptors(getInterceptors());
handlerMapping.setContentNegotiationManager(mvcContentNegotiationManager());
PathMatchConfigurer configurer = getPathMatchConfigurer();
if (configurer.isUseSuffixPatternMatch() != null) {
handlerMapping.setUseSuffixPatternMatch(configurer.isUseSuffixPatternMatch());
}
if (configurer.isUseRegisteredSuffixPatternMatch() != null) {
handlerMapping.setUseRegisteredSuffixPatternMatch(configurer.isUseRegisteredSuffixPatternMatch());
}
if (configurer.isUseTrailingSlashMatch() != null) {
handlerMapping.setUseTrailingSlashMatch(configurer.isUseTrailingSlashMatch());
}
if (configurer.getPathMatcher() != null) {
handlerMapping.setPathMatcher(configurer.getPathMatcher());
}
if (configurer.getUrlPathHelper() != null) {
handlerMapping.setUrlPathHelper(configurer.getUrlPathHelper());
}
return handlerMapping;
}
}
然后我进行了配置
<bean class="....WebConfig" />