स्प्रिंग 3 में @ क्रॉसऑरिगिन एनोटेशन कैसे करें?

Question

मैं इस तरह @CrossOrigin क्या करना चाहते हैं:

@CrossOrigin(origins = "http://domain2.com") 
@RequestMapping("/{id}") 
public Account retrieve(@PathVariable Long id) { 
    // ... 
} 

(स्प्रिंग से 4 मान लिया जाये कि उन्नयन विवश है) मैं वसंत 3 के साथ इस समय क्या करना है इस तरह दिखता है:

public class CORSFilter implements Filter { 
    public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws IOException, ServletException { 
     HttpServletResponse response = (HttpServletResponse) res; 
     HttpServletRequest request= (HttpServletRequest) req; 
     response.setHeader("Access-Control-Allow-Origin", "*"); 
     response.setHeader("Access-Control-Allow-Methods", "POST, GET, OPTIONS, DELETE"); 
     response.setHeader("Access-Control-Allow-Headers", "x-requested-with"); 
     response.setHeader("Access-Control-Expose-Headers", "x-requested-with"); chain.doFilter(req, res); 
    } 
} 

ध्यान दें कि स्प्रिंग 4.2 is here में @CrossOrigin के कार्यान्वयन के लिए स्रोत।

मेरा प्रश्न है: स्प्रिंग 3 में @ क्रॉसऑरिगिन एनोटेशन कैसे करें?

Answer 1

आप इसे इस तरह कार्य करें:

package com.mycompany; 

import java.lang.annotation.ElementType; 
import java.lang.annotation.Retention; 
import java.lang.annotation.RetentionPolicy; 
import java.lang.annotation.Target; 

@Target(ElementType.METHOD) 
@Retention(RetentionPolicy.RUNTIME) 
public @interface Spring3CorsFilter {} 

---

package com.mycompany; 

import org.springframework.web.method.HandlerMethod; 
import org.springframework.web.servlet.handler.HandlerInterceptorAdapter; 

import javax.servlet.http.HttpServletRequest; 
import javax.servlet.http.HttpServletResponse; 

/** 
* The purpose of this class is to emulate the Spring 4 annotation @CORSFilter - using the power of Spring 3 
* Note that is is constrained to non-prod environments 
*/ 
public class Spring3CorsFilterHandlerInterceptor extends HandlerInterceptorAdapter { 

    @Override 
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws 
      Exception { 

     if (handler instanceof HandlerMethod) { 
      HandlerMethod handlerMethod = (HandlerMethod) handler; 
      // Test if the controller-method is annotated with @Spring3CORSFilter 
      Spring3CorsFilter filter = handlerMethod.getMethod().getAnnotation(Spring3CorsFilter.class); 
      if (filter != null) { 
       // ... do the filtering 
       response.setHeader("Access-Control-Allow-Origin", "*"); 
       response.setHeader("Access-Control-Allow-Methods", "POST, GET, OPTIONS, DELETE"); 
       response.setHeader("Access-Control-Max-Age", "3600"); 
       response.setHeader("Access-Control-Allow-Headers", "x-requested-with"); 
      } 
     } 
     return true; 
    } 
} 

---

package com.mycompany; 

import com.google.common.base.Optional; 
import com.google.common.collect.FluentIterable; 
import org.junit.Test; 
import org.junit.runner.RunWith; 
import org.springframework.beans.factory.annotation.Autowired; 
import org.springframework.mock.web.MockHttpServletRequest; 
import org.springframework.mock.web.MockHttpServletResponse; 
import org.springframework.test.context.ContextConfiguration; 
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner; 
import org.springframework.test.context.support.AnnotationConfigContextLoader; 
import org.springframework.web.servlet.HandlerExecutionChain; 
import org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping; 

import java.util.Arrays; 
import java.util.Set; 

import static junit.framework.TestCase.assertTrue; 
import static org.junit.Assert.assertFalse; 


@RunWith(SpringJUnit4ClassRunner.class) 
public class Spring3CorsFilterHandlerInterceptorTest { 

    @Autowired 
    private RequestMappingHandlerMapping requestMappingHandlerMapping; 

    @Test 
    public void interceptor_is_on_request() throws Exception { 
     MockHttpServletRequest request = new MockHttpServletRequest("GET", 
       "/public/version"); 

     HandlerExecutionChain handlerExecutionChain = requestMappingHandlerMapping.getHandler(request); 

     Optional<Spring3CorsFilterHandlerInterceptor> containsHandler = FluentIterable 
       .from(Arrays.asList(handlerExecutionChain.getInterceptors())) 
       .filter(Spring3CorsFilterHandlerInterceptor.class).first(); 

     // Note that this will be present for all requests due to the mapping in spring-security.xml 
     assertTrue(containsHandler.isPresent()); 
    } 

    @Test 
    public void interceptor_is_not_run_on_non_annotated_request() throws Exception { 
    MockHttpServletRequest request = new MockHttpServletRequest("GET", 
       "/public/home"); 

     HandlerExecutionChain handlerExecutionChain = requestMappingHandlerMapping.getHandler(request); 

     Optional<Spring3CorsFilterHandlerInterceptor> containsHandler = FluentIterable 
       .from(Arrays.asList(handlerExecutionChain.getInterceptors())) 
       .filter(Spring3CorsFilterHandlerInterceptor.class).first(); 

     MockHttpServletResponse response = new MockHttpServletResponse(); 

     Spring3CorsFilterHandlerInterceptor handlerInterceptor = containsHandler.get(); 
     handlerInterceptor.preHandle(request, response, handlerExecutionChain.getHandler()); 

     Set<String> headerNames = response.getHeaderNames(); 
     assertFalse(headerNames.contains("Access-Control-Allow-Origin")); 
     assertFalse(headerNames.contains("Access-Control-Allow-Methods")); 
     assertFalse(headerNames.contains("Access-Control-Max-Age")); 
     assertFalse(headerNames.contains("Access-Control-Allow-Headers")); 
    } 

    @Test 
    public void interceptor_runs_on_annotated_request() throws Exception { 

     MockHttpServletRequest request = new MockHttpServletRequest("GET", 
       "/public/version"); 
     MockHttpServletResponse response = new MockHttpServletResponse(); 

     HandlerExecutionChain handlerExecutionChain = requestMappingHandlerMapping.getHandler(request); 

     Optional<Spring3CorsFilterHandlerInterceptor> containsHandler = FluentIterable 
       .from(Arrays.asList(handlerExecutionChain.getInterceptors())) 
       .filter(Spring3CorsFilterHandlerInterceptor.class).first(); 

     Spring3CorsFilterHandlerInterceptor handlerInterceptor = containsHandler.get(); 
     handlerInterceptor.preHandle(request, response, handlerExecutionChain.getHandler()); 

     Set<String> headerNames = response.getHeaderNames(); 
     assertTrue(headerNames.contains("Access-Control-Allow-Origin")); 
     assertTrue(headerNames.contains("Access-Control-Allow-Methods")); 
     assertTrue(headerNames.contains("Access-Control-Max-Age")); 
     assertTrue(headerNames.contains("Access-Control-Allow-Headers")); 
    } 
} 

Answer 2

आप नहीं करते; कार्यक्षमता 4.2 तक नहीं जोड़ा गया था (स्प्रिंग 4 श्रृंखला ने कैशिंग और सीओआरएस जैसी वेब प्रौद्योगिकियों पर ध्यान केंद्रित किया है)। सबसे अच्छा आप कर सकते हैं पहलू उन्मुख दृष्टिकोण, जो आपके Filter प्रदान करता है, या यदि आप अधिक बारीकता चाहते हैं, तो आप अपना खुद का HandlerInterceptor लिख सकते हैं जो 4.2 में जोड़े गए कार्यक्षमता को डुप्लिकेट करता है।