RestFul風格

特點：

• 簡潔
• 高效
• 安全

@Controller
public class RestFulController {
	//原來的: http://localhost:8080/add?a=1&b=2
	//RestFul: http://localhost:8080/add/a/b
    
    
	@RequestMapping("/add/{a}/{b}")
        //@RequestMapping(Value="/add/{a}/{b}",Method="RequestMethod.Post")
	public String test1 (@PathVariable int a, @PathVariable String b, Model model){
		String res = a + b;
		model.addAttribute("msg","結果為"+res);
		return "test" ;
	}
}
 

JSON

1、返回物件格式

@Controller
public class UserController {
    @RequestMapping("/j1")
    @ResponseBody //它就不會走檢視解析器，會直接返回一個字串
    public String json1(){
        //建立一個物件
        User user = new User("張三",20,"男");
        return user.toString();
    }
}

2、返回 JSON格式

@Controller
public class UserController{
@RequestMapping(value="/j1" , produces="application/json;charset=utf-8")
@ResponseBody //它就不會走檢視解析器，會直接返回一個字串
public String json1() throws JsonProcessingException {
    //jackson, objectMapper
    ObjectMapper mapper = new ObjectMapper();
    //建立一個物件
    User user = new User("張三",20,"男");
    String str = mapper.writeValueAsString(user);
    return str;
    }
}
 

<!--固定的，使用了jackson包就需要配置-->
<!--JSON亂碼問題配置-->
<mvc:annotation-driven>
    <mvc:message-converters register-defaults="true">
        <bean class="org.springframework.http.converter.StringHttpMessageConverter">
        	<constructor-arg value="UTF-8"/>
        </bean>
        <bean class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter">
            <property name= "objectMapper">
                <bean class="org.springframework.http.converter.json.Jackson20bjectMapperFactoryBean">
                    <property name= "failOnEmptyBeans" value="false" />
                </bean>
            </property>
        </bean>
    </mvc:message-converters>
</mvc:annotation-driven>
 

拓展：返回時間戳格式的 JSON字串

@RequestMapping("/j3")
public String json3() throws JsonProcessingException {
    objectMapper mapper = new ObjectMapper();
    Date date = new Date();
    //objectMapper,時間解析後的預設格式為: Timestamp(時間戳)
    return mapper.writeValueAsString(date);
}

或者：

@RequestMapping("/j3")
public String json3() throws JsonProcessingException {
    objectMapper mapper = new objectMapper();
    //不使用時間戳的方式
    mapper.configure (SerializationFeature.WRITE_DATES_AS_TIMESTAMPS , false);
    //自定義日期的格式
    SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
    mapper.setDateFormat(sdf);
    Date date = new Date();
    //objectMapper,時間解析後的預設格式為: Timestamp, 時間戳
    return mapper.writeValueAsString(date);
}