我有一个简单的 Web 服务返回JSON data.
The 用户等级 (com.bargadss.SpringService.Domain) 是个POJO类包含
用户 ID、名字、姓氏、电子邮件
The 用户服务类 (com.bargadss.SpringService.DAO) 两大操作
- getAllUser() -> 查询数据库Select用户表中的所有用户和returns列表{用户}
- getUserById(int user_ID) -> 查询数据库Select基于ID的特定用户
The Spring服务控制器 (com.bargadss.SpringService.Controller)如下:
package com.bargadss.SpringService.Controller;
import java.util.List;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;
import com.bargadss.SpringService.DAO.UserService;
import com.bargadss.SpringService.Domain.User;
@RestController
@RequestMapping("/service/user/")
public class SpringServiceController {
UserService userService=new UserService();
@RequestMapping(value = "/{id}", method = RequestMethod.GET,headers="Accept=application/json")
public User getUser(@PathVariable int id) {
User user=userService.getUserById(id);
return user;
}
@RequestMapping(method = RequestMethod.GET,headers="Accept=application/json")
public List<User> getAllUsers() {
List<User> users=userService.getAllUsers();
return users;
}
}
The 列表用户控制器 (com.bargadss.SpringService.Controller)如下:
package com.bargadss.SpringService.Controller;
import java.util.LinkedHashMap;
import java.util.List;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.client.RestTemplate;
import org.springframework.web.servlet.ModelAndView;
import com.bargadss.SpringService.Domain.User;
@Controller
public class ListUserController {
@RequestMapping("/listUsers")
public ModelAndView listUsers() {
RestTemplate restTemplate = new RestTemplate();
String url="http://localhost:8080/SpringServiceWithRESTAndJSONExample/service/user/";
List<LinkedHashMap> users=restTemplate.getForObject(url, List.class);
return new ModelAndView("listUsers", "users", users);
}
@RequestMapping("/dispUser/{userid}")
public ModelAndView dispUser(@PathVariable("userid") int userid) {
RestTemplate restTemplate = new RestTemplate();
String url="http://localhost:8080/SpringServiceWithRESTAndJSONExample/service/user/{userid}";
User user=restTemplate.getForObject(url, User.class,userid);
return new ModelAndView("dispUser", "user", user);
}
}
The 过滤器 (com.bargadss.CORS)如下:
package com.bargadss.CORS;
import java.io.IOException;
import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.springframework.web.filter.OncePerRequestFilter;
public class CorsFilter extends OncePerRequestFilter{
@Override
protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain filterChain)
throws ServletException, IOException {
if (request.getHeader("Access-Control-Request-Method") != null && "OPTIONS".equals(request.getMethod())) {
// CORS "pre-flight" request
response.addHeader("Access-Control-Allow-Origin", "*");
response.addHeader("Access-Control-Allow-Methods", "GET, POST, PUT, DELETE");
response.addHeader("Access-Control-Allow-Headers", "Content-Type");
response.addHeader("Access-Control-Max-Age", "1800");//30 min
}
filterChain.doFilter(request, response);
}
}
The web.xml如下:
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
id="WebApp_ID" version="3.0">
<display-name>SpringServiceWithRESTAndJSONExample</display-name>
<servlet>
<servlet-name>rest</servlet-name>
<servlet-class>
org.springframework.web.servlet.DispatcherServlet
</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet>
<servlet-name>jsp</servlet-name>
<servlet-class>org.apache.jasper.servlet.JspServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>rest</servlet-name>
<url-pattern>/*</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>jsp</servlet-name>
<url-pattern>/WEB-INF/jsp/*</url-pattern>
</servlet-mapping>
<filter>
<filter-name>cors</filter-name>
<filter-class>com.bargadss.CORS.CorsFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>cors</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
</web-app>
当 AngularJS 从另一个 Web 服务器调用 Web 服务时,会返回错误,涉及跨源资源共享问题!
必须在控制器侧执行哪些更改才能消除错误?
AngularJS 方面是否需要进行任何更改以避免这种情况?