❶ Jackjson如何将反序列化的数据传到jsp页面
如果你使用的是servlet,可以先保存数据到request: request.setAttribute("key",反序列化对象数据)；然后forward到jsp页面：request.getRequestDispatcher("jsp页面").forward(request,response);
在jsp中获取数据request.getAttribute("key");使用。
当然，你也可以使用session、application 暂存数据，但是别忘了使用后remove他们。
❷ springmvc jackon 为什么不返回json
SpringMvc配置：
<!--启动SpringMVC的注解功能，完成请求和注解POJO的映射-->
<beanclass="org.springframework.web.servlet.mvc.annotation.">
<propertyname="messageConverters">
<list>
<!--json转换器-->
<refbean=""/>
</list>
</property>
</bean>
<beanclass="org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter">
<propertyname="messageConverters">
<list>
<refbean=""/>
</list>
</property>
</bean>
<beanid=""
class="org.springframework.http.converter.json.">
<propertyname="supportedMediaTypes">
<list>
<beanclass="org.springframework.http.MediaType">
<constructor-argindex="0"value="text"/>
<constructor-argindex="1"value="plain"/>
<constructor-argindex="2"value="UTF-8"/>
</bean>
<beanclass="org.springframework.http.MediaType">
<constructor-argindex="0"value="*"/>
<constructor-argindex="1"value="*"/>
<constructor-argindex="2"value="UTF-8"/>
</bean>
<beanclass="org.springframework.http.MediaType">
<constructor-argindex="0"value="text"/>
<constructor-argindex="1"value="*"/>
<constructor-argindex="2"value="UTF-8"/>
</bean>
<beanclass="org.springframework.http.MediaType">
<constructor-argindex="0"value="application"/>
<constructor-argindex="1"value="json"/>
<constructor-argindex="2"value="UTF-8"/>
</bean>
</list>
</property>
</bean>
Controller代码
@RequestMapping(value="update",method=RequestMethod.POST)
@ResponseBody
publicMap<String,Object>update(SOUserentity,){
LonguserId=entity.getId();
Longuid=TokenManager.getUserId();
if(StringUtils.isBlank(userId,uid)||!uid.equals(userId)){
resultMap.put("status",500);
resultMap.put("message","非法修改！");
}else{
Stringname="portrait/"+userId;
Stringportrait=ImageManager.saveImages(name,request);
if(StringUtils.isNotBlank(portrait)){
entity.setPortrait(portrait);
}
userService.updateByPrimaryKeySelective(entity);
resultMap.put("status",200);
resultMap.put("message","修改成功！");
entity=userService.selectByPrimaryKey(userId);
//更新
TokenManager.login(entity);
}
returnresultMap;
}
❸ json 中如何使用@JsonIgnore
json 中使用@方法如下。
❹ 怎么返回得到的gson.fromjson
import com.google.gson.Gson;
public class TestJson
{
private int age;
private String name;
public String show()
{
return new String("name:" + name + "/age:" + age);
}
public static void main(String[] args)
{
String[] source =new String[]{
"",
"abc",
"{}",
"{\"nick_name\":\"Jack\"}",
"{\"name\":\"Anna\",\"id\":5}",
"{\"name\":\"Pluto\",\"age\":15,\"id\":10}"
};
Gson g=new Gson();
TestJson x=null;
StringBuffer info=null;
for(int i=0;i<source.length;i++)
{
info=new StringBuffer();
info.append(i).append(":").append(source[i]).append("\n\t");
try
{
x=g.fromJson(source[i], TestJson.class);
info.append((x == null) ? "NULL" : x.show());
}catch(Exception e)
{
info.append(e.getClass().getName());
}
System.out.println(info.toString());
}
}
}
❺ 如何给Swift字典Dictionary增加空值
有些情况下在Swift中想让Dictionary某个Key为空值,比如在与服务器交互时,有些参数无论有没有值必须要求传.但如果给字典的key赋值为nil,字典则会移除这个键值对,如下：
var dict1=Dictionary<String,AnyObject>()
dict1["name"]="Jack"
dict1["age"]=16
dict1["nickname"]=nil
println(dict1) //"[age: 16, name: Jack]"
let jsonData1 = NSJSONSerialization.dataWithJSONObject(dict1, options: NSJSONWritingOptions.allZeros, error: nil)!
let jsonString1 = NSString(data: jsonData1, encoding: NSUTF8StringEncoding)!
println(jsonString1) //"{"age":16,"name":"Jack"}"
如果像要字典的值为NULL,可以使用NSNULL,这样就可以达到像要的效果了：
var dict2=Dictionary<String,AnyObject>()
dict2["name"]="Jack"
dict2["age"]=16
dict2["nickname"]=NSNull()
println(dict2) //[age: 16, nickname: <null>, name: Jack]
let jsonData2 = NSJSONSerialization.dataWithJSONObject(dict2, options: NSJSONWritingOptions.allZeros, error: nil)!
let jsonString2 = NSString(data: jsonData2, encoding: NSUTF8StringEncoding)!
println(jsonString2) //{"age":16,"nickname":null,"name":"Jack"}
❻ elasticsearch 2.3.1 要使用什么版本的jackjson
Elasticsearch是一个全文搜索引擎。安装Elasticsearch时需要先安装Java。
要求的jdk版本1.7以上的。
以下是官方文档：
Elasticsearch requires at least Java 7. Specifically as of this writing, it is recommended that you use the Oracle JDK version 1.8.0_25. Java installation varies from platform to platform so we won’t go into those details here. Oracle’s recommended installation documentation can be found on Oracle’s website. Suffice to say, before you install Elasticsearch, please check your Java version first by running (and then install/upgrade accordingly if needed): 需要jdk1.7 以上版本