Jackson框架

以你之姓@ 2022-06-11 03:17 159阅读 0赞

**Jackson 框架**

**使用说明**

Jackson可以轻松的将Java对象转换成json对象和xml文档，同样也可以将json、xml转换成Java对象。

前面有介绍过json-lib这个框架，在线博文：[http://www.cnblogs.com/duanxz/archive/2013/05/03/3056174.html][http_www.cnblogs.com_duanxz_archive_2013_05_03_3056174.html]  
相比json-lib框架，Jackson所依赖的jar包较少，简单易用并且性能也要相对高些。而且Jackson社区相对比较活跃，更新速度也比较快。

**一、准备工作**

1、 下载依赖库jar包

Jackson的jar all下载地址：[http://jackson.codehaus.org/1.7.6/jackson-all-1.7.6.jar][http_jackson.codehaus.org_1.7.6_jackson-all-1.7.6.jar]

然后在工程中导入这个jar包即可开始工作

官方示例：[http://wiki.fasterxml.com/JacksonInFiveMinutes][http_wiki.fasterxml.com_JacksonInFiveMinutes]

因为下面的程序是用junit测试用例运行的，所以还得添加junit的jar包。版本是junit-4.2.8

如果你需要转换xml，那么还需要stax2-api.jar

2、 测试类基本代码如下(下面的代码还不能直接运行）

![复制代码][copycode.gif]

package com.dxz.json;
 
 import java.io.IOException;
 import org.codehaus.jackson.JsonEncoding;
 import org.codehaus.jackson.JsonGenerator;
 import org.codehaus.jackson.map.ObjectMapper;
 import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
 /**
 * function:Jackson 将java对象转换成JSON字符串，也可以将JSON字符串转换成java对象
 * jar-lib-version: jackson-all-1.6.2
 * @createDate 2010-11-23 下午04:54:53
 * @file JacksonTest.java
 */
 @SuppressWarnings("unchecked")
 public class JacksonTest{
 private JsonGenerator jsonGenerator = null;
 private ObjectMapper objectMapper = null;
 private AccountBean bean = null;
 
 @Before
 public void init() {
 bean = new AccountBean();
 bean.setAddress("china-Guangzhou");
 bean.setEmail("abc@gmail.com");
 bean.setId(1);
 bean.setName("duanxz");
 
 objectMapper = new ObjectMapper();
 try {
 jsonGenerator = objectMapper.getJsonFactory().createJsonGenerator(System.out, JsonEncoding.UTF8);
 } catch (IOException e) {
 e.printStackTrace();
 }
 }
 
 @After
 public void destory() {
 try {
 if (jsonGenerator != null) {
 jsonGenerator.flush();
 }
 if (!jsonGenerator.isClosed()) {
 jsonGenerator.close();
 }
 jsonGenerator = null;
 objectMapper = null;
 bean = null;
 System.gc();
 } catch (IOException e) {
 e.printStackTrace();
 }
 }
 }

![复制代码][copycode.gif]

3、 所需要的JavaEntity

AccountBean.java

![复制代码][copycode.gif]

/**
     * AccountBean
     */
    package com.dxz.json;
    
    public class AccountBean {
    private int id;
    private String name;
        private String email;
        private String address;
        private Birthday birthday;
        
        
        @Override
        public String toString() {
            return this.name + "#" + this.id + "#" + this.address + "#" + this.birthday + "#" + this.email;
        }
        
        //getter、setter
        public int getId() {
            return id;
        }
    
        public void setId(int id) {
            this.id = id;
        }
    
        public String getName() {
            return name;
        }
    
        public void setName(String name) {
            this.name = name;
        }
    
        public String getEmail() {
            return email;
        }
    
        public void setEmail(String email) {
            this.email = email;
        }
    
        public String getAddress() {
            return address;
        }
    
        public void setAddress(String address) {
            this.address = address;
        }
    
        public Birthday getBirthday() {
            return birthday;
        }
    
        public void setBirthday(Birthday birthday) {
            this.birthday = birthday;
        }
    }

![复制代码][copycode.gif]

Birthday.java

![复制代码][copycode.gif]

package com.dxz.json;
    
    public class Birthday {
        private String birthday;
        
        public Birthday(String birthday) {
            super();
            this.birthday = birthday;
        }
     
        //getter、setter
     
        public Birthday() {}
        
        @Override
        public String toString() {
            return this.birthday;
        }
    }

![复制代码][copycode.gif]

**二、Java对象转换成JSON**

1、 JavaBean(Entity/Model)转换成JSON（JacksonTest中的方法）

![复制代码][copycode.gif]

/**
 * function:将java对象转换成json字符串
 * @author hoojo
 * @createDate 2010-11-23 下午06:01:10
 */
 @Test
 public void writeEntityJSON() {
 
 try {
 System.out.println("jsonGenerator");
 //writeObject可以转换java对象，eg:JavaBean/Map/List/Array等
 jsonGenerator.writeObject(bean); 
 System.out.println();
 
 System.out.println("ObjectMapper");
 //writeValue具有和writeObject相同的功能
 objectMapper.writeValue(System.out, bean);
 } catch (IOException e) {
 e.printStackTrace();
 }
 }

![复制代码][copycode.gif]

该方法执行结果：

jsonGenerator
    {"email":"abc@gmail.com","birthday":null,"address":"china-Guangzhou","name":"duanxz","id":1}
    ObjectMapper
    {"email":"abc@gmail.com","birthday":null,"address":"china-Guangzhou","name":"duanxz","id":1}

上面分别利用JsonGenerator的writeObject方法和ObjectMapper的writeValue方法完成对Java对象的转换，二者传递的参数及构造的方式不同；JsonGenerator的创建依赖于ObjectMapper对象。也就是说如果你要使用JsonGenerator来转换JSON，那么你必须创建一个ObjectMapper。但是你用ObjectMapper来转换JSON，则不需要JSONGenerator。

*  objectMapper的writeValue方法可以将一个Java对象转换成JSON。这个方法的参数一，需要提供一个输出流，转换后可以通过这个流来输出转换后的内容。或是提供一个File，将转换后的内容写入到File中。当然，这个参数也可以接收一个JSONGenerator，然后通过JSONGenerator来输出转换后的信息。第二个参数是将要被转换的Java对象。如果用三个参数的方法，那么是一个Config。这个config可以提供一些转换时的规则，过指定的Java对象的某些属性进行过滤或转换等。

2、 将Map集合转换成Json字符串

![复制代码][copycode.gif]

/**
 * function:将map转换成json字符串
 * @createDate 2010-11-23 下午06:05:26
 */
 @Test
 public void writeMapJSON() {
 try {
 Map<String, Object> map = new HashMap<String, Object>();
 map.put("name", bean.getName());
 map.put("account", bean);
 bean = new AccountBean();
 bean.setAddress("china-Beijin");
 bean.setEmail("hoojo@qq.com");
 map.put("account2", bean);
 System.out.println("writeMapJSON*****jsonGenerator");
 jsonGenerator.writeObject(map);
 System.out.println("");
 System.out.println("writeMapJSON*****objectMapper");
 objectMapper.writeValue(System.out, map);
 } catch (IOException e) {
 e.printStackTrace();
 }
 }

![复制代码][copycode.gif]

转换后结果如下：

![复制代码][copycode.gif]

writeMapJSON*****jsonGenerator
    {"account2":{"email":"hoojo@qq.com","birthday":null,"address":"china-Beijin","name":null,"id":0},"name":"duanxz","account":{"email":"abc@gmail.com","birthday":null,"address":"china-Guangzhou","name":"duanxz","id":1}}
    writeMapJSON*****objectMapper
    {"account2":{"email":"hoojo@qq.com","birthday":null,"address":"china-Beijin","name":null,"id":0},"name":"duanxz","account":{"email":"abc@gmail.com","birthday":null,"address":"china-Guangzhou","name":"duanxz","id":1}}

![复制代码][copycode.gif]

3、 将List集合转换成json

![复制代码][copycode.gif]

/**
 * function:将list集合转换成json字符串
 */
 @Test
 public void writeListJSON() {
 try {
 List<AccountBean> list = new ArrayList<AccountBean>();
 list.add(bean);
 bean = new AccountBean();
 bean.setId(2);
 bean.setAddress("address2");
 bean.setEmail("email2");
 bean.setName("haha2");
 list.add(bean);
 System.out.println("jsonGenerator");
 // list转换成JSON字符串
 jsonGenerator.writeObject(list);
 System.out.println();
 System.out.println("ObjectMapper");
 // 用objectMapper直接返回list转换成的JSON字符串
 System.out.println("1###" + objectMapper.writeValueAsString(list));
 System.out.print("2###");
 // objectMapper list转换成JSON字符串
 objectMapper.writeValue(System.out, list);
 } catch (IOException e) {
 e.printStackTrace();
 }
 }

![复制代码][copycode.gif]

结果如下：

![复制代码][copycode.gif]

jsonGenerator
    [{"email":"abc@gmail.com","birthday":null,"address":"china-Guangzhou","name":"duanxz","id":1},{"email":"email2","birthday":null,"address":"address2","name":"haha2","id":2}]
    ObjectMapper
    1###[{"email":"abc@gmail.com","birthday":null,"address":"china-Guangzhou","name":"duanxz","id":1},{"email":"email2","birthday":null,"address":"address2","name":"haha2","id":2}]
    2###[{"email":"abc@gmail.com","birthday":null,"address":"china-Guangzhou","name":"duanxz","id":1},{"email":"email2","birthday":null,"address":"address2","name":"haha2","id":2}]

![复制代码][copycode.gif]

外面就是多了个\[\]中括号；同样Array也可以转换，转换的JSON和上面的结果是一样的，这里就不再转换了。~.~

4、下面来看看jackson提供的一些类型，用这些类型完成json转换；如果你使用这些类型转换JSON的话，那么你即使没有JavaBean(Entity)也可以完成复杂的Java类型的JSON转换。下面用到这些类型构建一个复杂的Java对象，并完成JSON转换。

![复制代码][copycode.gif]

@Test
        public void writeOthersJSON() {
            try {
                String[] arr = { "a", "b", "c" };
                System.out.println("jsonGenerator");
                String str = "hello world jackson!";
                // byte
                jsonGenerator.writeBinary(str.getBytes());
                // boolean
                jsonGenerator.writeBoolean(true);
                // null
                jsonGenerator.writeNull();
                // float
                jsonGenerator.writeNumber(2.2f);
                // char
                jsonGenerator.writeRaw("c");
                // String
                jsonGenerator.writeRaw(str, 5, 10);
                // String
                jsonGenerator.writeRawValue(str, 5, 5);
                // String
                jsonGenerator.writeString(str);
                jsonGenerator.writeTree(JsonNodeFactory.instance.POJONode(str));
                System.out.println();
                // Object
                jsonGenerator.writeStartObject();// {
                jsonGenerator.writeObjectFieldStart("user");// user:{
                jsonGenerator.writeStringField("name", "jackson");// name:jackson
                jsonGenerator.writeBooleanField("sex", true);// sex:true
                jsonGenerator.writeNumberField("age", 22);// age:22
                jsonGenerator.writeEndObject();// }
                jsonGenerator.writeArrayFieldStart("infos");// infos:[
                jsonGenerator.writeNumber(22);// 22
                jsonGenerator.writeString("this is array");// this is array
                jsonGenerator.writeEndArray();// ]
                jsonGenerator.writeEndObject();// }
                AccountBean bean = new AccountBean();
                bean.setAddress("address");
                bean.setEmail("email");
                bean.setId(1);
                bean.setName("haha");
                // complex Object
                jsonGenerator.writeStartObject();// {
                jsonGenerator.writeObjectField("user", bean);// user:{bean}
                jsonGenerator.writeObjectField("infos", arr);// infos:[array]
                jsonGenerator.writeEndObject();// }
            } catch (Exception e) {
                e.printStackTrace();
            }
        }

![复制代码][copycode.gif]

运行后，结果如下：

jsonGenerator
    "aGVsbG8gd29ybGQgamFja3NvbiE=" true null 2.2c world jac  worl "hello world jackson!" "hello world jackson!"
     {"user":{"name":"jackson","sex":true,"age":22},"infos":[22,"this is array"]} {"user":{"email":"email","birthday":null,"address":"address","name":"haha","id":1},"infos":["a","b","c"]}

怎么样？构造的json字符串和输出的结果是一致的吧。关键看懂用JSONGenerator提供的方法，完成一个Object的构建。

**三、JSON转换成Java对象**

1、 将json字符串转换成JavaBean对象

![复制代码][copycode.gif]

@Test
        public void readJson2Entity() {
              String json = "{\"address\":\"address\",\"name\":\"haha\",\"id\":1,\"email\":\"email\"}";
              try {
                    AccountBean acc = objectMapper.readValue(json, AccountBean.class);
                    System.out.println(acc.getName());
                    System.out.println(acc);
              } catch (JsonParseException e) {
                    e.printStackTrace();
              } catch (JsonMappingException e) {
                    e.printStackTrace();
              } catch (IOException e) {
                    e.printStackTrace();
              }
        }

![复制代码][copycode.gif]

很简单，用到了ObjectMapper这个对象的readValue这个方法，这个方法需要提供2个参数。第一个参数就是解析的JSON字符串，第二个参数是即将将这个JSON解析吃什么Java对象，Java对象的类型。当然，还有其他相同签名方法，如果你有兴趣可以一一尝试使用方法，当然使用的方法和当前使用的方法大同小异。运行后，结果如下：

haha
    haha#1#address#null#email

2、 将json字符串转换成List<Map>集合

![复制代码][copycode.gif]

/**
 * function:json字符串转换成list<map>
 */
 @Test
 public void readJson2List() {
 String json = "[{\"address\": \"address2\",\"name\":\"haha2\",\"id\":2,\"email\":\"email2\"},{\"address\":\"address\",\"name\":\"haha\",\"id\":1,\"email\":\"email\"}]";
 try {
 List<LinkedHashMap<String, Object>> list = objectMapper.readValue(
 json, List.class);
 System.out.println(list.size());
 for (int i = 0; i < list.size(); i++) {
 Map<String, Object> map = list.get(i);
 Set<String> set = map.keySet();
 for (Iterator<String> it = set.iterator(); it.hasNext();) {
 String key = it.next();
 System.out.println(key + ":" + map.get(key));
 }
 }
 } catch (JsonParseException e) {
 e.printStackTrace();
 } catch (JsonMappingException e) {
 e.printStackTrace();
 } catch (IOException e) {
 e.printStackTrace();
 }
 }

![复制代码][copycode.gif]

尝试过将上面的JSON转换成List，然后List中存放AccountBean，但结果失败了。但是支持Map集合。因为你转成List.class，但是不知道List存放何种类型。只好默然Map类型。因为所有的对象都可以转换成Map结合，运行后结果如下：

![复制代码][copycode.gif]

2
    address:address2
    name:haha2
    id:2
    email:email2
    address:address
    name:haha
    id:1
    email:email

![复制代码][copycode.gif]

3、 Json字符串转换成Array数组，由于上面的泛型转换不能识别到集合中的对象类型。所有这里用对象数组，可以解决这个问题。只不过它不再是集合，而是一个数组。当然这个不重要，你可以用Arrays.asList将其转换成List即可。

![复制代码][copycode.gif]

/**
 * function:json字符串转换成Array
 */
 @Test
 public void readJson2Array() {
 String json = "[{\"address\": \"address2\",\"name\":\"haha2\",\"id\":2,\"email\":\"email2\"},{\"address\":\"address\",\"name\":\"haha\",\"id\":1,\"email\":\"email\"}]";
 try {
 AccountBean[] arr = objectMapper.readValue(json,
 AccountBean[].class);
 System.out.println(arr.length);
 for (int i = 0; i < arr.length; i++) {
 System.out.println(arr[i]);
 }
 } catch (JsonParseException e) {
 e.printStackTrace();
 } catch (JsonMappingException e) {
 e.printStackTrace();
 } catch (IOException e) {
 e.printStackTrace();
 }
 }

![复制代码][copycode.gif]

运行后的结果：

2
    haha2#2#address2#null#email2
    haha#1#address#null#email

4、 Json字符串转换成Map集合

![复制代码][copycode.gif]

/**
 * function:json字符串转换Map集合
 */
 @Test
 public void readJson2Map() {
 String json = "{\"success\":true,\"A\":{\"address\": \"address2\",\"name\":\"haha2\",\"id\":2,\"email\":\"email2\"},\"B\":{\"address\":\"address\",\"name\":\"haha\",\"id\":1,\"email\":\"email\"}}";
 try {
 Map<String, Map<String, Object>> maps = objectMapper.readValue(
 json, Map.class);
 System.out.println(maps.size());
 Set<String> key = maps.keySet();
 Iterator<String> iter = key.iterator();
 while (iter.hasNext()) {
 String field = iter.next();
 System.out.println(field + ":" + maps.get(field));
 }
 } catch (JsonParseException e) {
 e.printStackTrace();
 } catch (JsonMappingException e) {
 e.printStackTrace();
 } catch (IOException e) {
 e.printStackTrace();
 }
 }

![复制代码][copycode.gif]

运行后结果如下：

3
    success:true
    A:{address=address2, name=haha2, id=2, email=email2}
    B:{address=address, name=haha, id=1, email=email}

**四、Jackson对XML的支持**

Jackson也可以完成java对象到xml的转换，转换后的结果要比json-lib更直观，不过它依赖于stax2-api.jar这个jar包。

<table> 
 <tbody> 
 <tr> 
 <td> /** &nbsp;* &lt;b&gt;function:&lt;/b&gt;java对象转换成xml文档 &nbsp;* 需要额外的jar包 stax2-api.jar &nbsp;*&nbsp;@author&nbsp;hoojo &nbsp;*&nbsp;@createDate&nbsp;2010-11-23 下午06:11:21 &nbsp;*/ @Test public&nbsp;void&nbsp;writeObject2Xml() { &nbsp;&nbsp;&nbsp;&nbsp;&nbsp; //stax2-api-3.0.2.jar &nbsp;&nbsp;&nbsp;&nbsp;&nbsp; System.out.println("XmlMapper"); &nbsp;&nbsp;&nbsp;&nbsp;&nbsp; XmlMapper xml =&nbsp;new&nbsp;XmlMapper(); &nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;try&nbsp;{ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; //javaBean转换成xml &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; //xml.writeValue(System.out, bean); &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; StringWriter sw =&nbsp;new&nbsp;StringWriter(); &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; xml.writeValue(sw, bean); &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; System.out.println(sw.toString()); &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; //List转换成xml &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; List&lt;AccountBean&gt; list =&nbsp;new&nbsp;ArrayList&lt;AccountBean&gt;(); &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; list.add(bean); &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; list.add(bean); &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; System.out.println(xml.writeValueAsString(list)); &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; //Map转换xml文档 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Map&lt;String, AccountBean&gt; map =&nbsp;new&nbsp;HashMap&lt;String, AccountBean&gt;(); &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; map.put("A", bean); &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; map.put("B", bean); &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; System.out.println(xml.writeValueAsString(map)); &nbsp;&nbsp;&nbsp;&nbsp;&nbsp; }&nbsp;catch&nbsp;(JsonGenerationException e) { &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; e.printStackTrace(); &nbsp;&nbsp;&nbsp;&nbsp;&nbsp; }&nbsp;catch&nbsp;(JsonMappingException e) { &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; e.printStackTrace(); &nbsp;&nbsp;&nbsp;&nbsp;&nbsp; }&nbsp;catch&nbsp;(IOException e) { &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; e.printStackTrace(); &nbsp;&nbsp;&nbsp;&nbsp;&nbsp; } } </td> 
 </tr> 
 </tbody> 
</table>

运行上面的方法，结果如下：

<table> 
 <tbody> 
 <tr> 
 <td> XmlMapper &lt;unknown&gt;&lt;address&gt;china-Guangzhou&lt;/address&gt;&lt;name&gt;hoojo&lt;/name&gt;&lt;id&gt;1&lt;/id&gt;&lt;birthday/&gt;&lt;email&gt;hoojo_@126.com&lt;/email&gt;&lt;/unknown&gt; &lt;unknown&gt;&lt;unknown&gt;&lt;address&gt;china-Guangzhou&lt;/address&gt;&lt;name&gt;hoojo&lt;/name&gt;&lt;id&gt;1&lt;/id&gt;&lt;birthday/&gt;&lt;email&gt;hoojo_@126.com&lt;/email&gt;&lt;/unknown&gt;&lt;email&gt;&lt;address&gt;china-Guangzhou&lt;/address&gt;&lt;name&gt;hoojo&lt;/name&gt;&lt;id&gt;1&lt;/id&gt;&lt;birthday/&gt;&lt;email&gt;hoojo_@126.com&lt;/email&gt;&lt;/email&gt;&lt;/unknown&gt; &lt;unknown&gt;&lt;A&gt;&lt;address&gt;china-Guangzhou&lt;/address&gt;&lt;name&gt;hoojo&lt;/name&gt;&lt;id&gt;1&lt;/id&gt;&lt;birthday/&gt;&lt;email&gt;hoojo_@126.com&lt;/email&gt;&lt;/A&gt;&lt;B&gt;&lt;address&gt;china-Guangzhou&lt;/address&gt;&lt;name&gt;hoojo&lt;/name&gt;&lt;id&gt;1&lt;/id&gt;&lt;birthday/&gt;&lt;email&gt;hoojo_@126.com&lt;/email&gt;&lt;/B&gt;&lt;/unknown&gt; </td> 
 </tr> 
 </tbody> 
</table>

看结果，根节点都是unknown 这个问题还没有解决，由于根节点没有转换出来，所有导致解析xml到Java对象，也无法完成。

[http_www.cnblogs.com_duanxz_archive_2013_05_03_3056174.html]: http://www.cnblogs.com/duanxz/archive/2013/05/03/3056174.html
[http_jackson.codehaus.org_1.7.6_jackson-all-1.7.6.jar]: http://jackson.codehaus.org/1.7.6/jackson-all-1.7.6.jar
[http_wiki.fasterxml.com_JacksonInFiveMinutes]: http://wiki.fasterxml.com/JacksonInFiveMinutes
[copycode.gif]: /images/20220611/af6ddb39b64247a7a38addc38855bd63.png