详细解决方案
用 Jackson 来处置 JSON
热度：620 发布时间：2012-12-25 16:18:28.0
用 Jackson 来处理 JSON
[代码] 首先创建一个User对象类 (User.java)
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package com.sivalabs.json;
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?
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import java.util.Date;
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??
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public class User {
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?private String userId;
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?private UserName userName;
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?private Date dob;
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???
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?@Override
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?public String toString(){
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??return "User [dob=" + dob + ", userId=" + userId + ", userName="+ userName + "]";
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?}
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?//setters and getters
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???
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}
[代码] UserName.java
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package com.sivalabs.json;
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?
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public class UserName {
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?private String firstname;
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?private String middlename;
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?private String lastname;
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???
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?@Override
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?public String toString()
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?{
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??return "UserName [firstname=" + firstname +
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??", lastname=" + lastname+
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??", middlename=" + middlename + "]";
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?}
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?//setters and getters
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}
[代码] [Java]代码
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//接下来创建User实例，并生成JSON数据
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?
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ObjectMapper mapper = new ObjectMapper();
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??
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UserName userName = new UserName();
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userName.setFirstname("Katamreddy");
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userName.setMiddlename("Siva");
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userName.setLastname("PrasadReddy");
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??
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User user = new User();
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user.setUserId("1");
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user.setUserName(userName);
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user.setDob(new Date());
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??
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Writer strWriter = new StringWriter();
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mapper.writeValue(strWriter, user);
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String userDataJSON = strWriter.toString();
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System.out.println(userDataJSON);
[代码] 执行结果
view sourceprint?
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{
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"userId":"1",
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"userName":
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{
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"firstname":"Katamreddy",
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"middlename":"Siva",
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"lastname":"PrasadReddy"
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},
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"dob":1300878089906
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}
[代码] 接下来进行JSON到Java对象的转换
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String userDataJSON =
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"{\"userId\":\"100\",\"userName\":{\"firstname\":\"K\""+
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",\"middlename\":\"Siva\",\"lastname\":\"Prasad\"},\"dob\":1300878089906}";
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User userFromJSON = mapper.readValue(userDataJSON, User.class);
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System.out.println(userFromJSON);
[代码] 时间的格式化处理
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DateFormat dateFormat = new SimpleDateFormat("MM-dd-yyyy");
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SerializationConfig serConfig = mapper.getSerializationConfig();
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serConfig.setDateFormat(dateFormat);
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DeserializationConfig deserializationConfig = mapper.getDeserializationConfig();
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deserializationConfig.setDateFormat(dateFormat);
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mapper.configure(SerializationConfig.Feature.WRITE_DATES_AS_TIMESTAMPS, false);
[代码] [Java]代码
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//从文件中读取JSON数据
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User user = mapper.readValue(new File("user.json"), User.class);