如何使用jackson美化输出json/xml

1.美化POJO序列化xml

下面将POJO列化为xml并打印。

Person person = new Person();
//设置person属性
ObjectMapper mapper = new XmlMapper();


System.out.println(mapper.writeValueAsString(person));


但是输出为紧凑模式:

<Person><name>Hello world</name><age>12</age></Person>


2.目的:美化过的输出

有时希望能够美化输出,更方便阅读和理解,如:

<Person><name>Hello world</name><age>12</age></Person>


方式1.使用:writerWithDefaultPrettyPrinter

ObjectMapper mapper = new XmlMapper();
System.out.println(mapper.writerWithDefaultPrettyPrinter().writeValueAsString(person));
mapper.enable(SerializationFeature.INDENT_OUTPUT);


方式2.使用:SerializationFeature.INDENT_OUTPUT

ObjectMapper mapper = new XmlMapper();
mapper.enable(SerializationFeature.INDENT_OUTPUT);
mapper.writeValueAsString(person);


3.序列化为json

序列化为json时,操作基本一致,只需要使用ObjectMapper替代XmlMapper。如:

Person person = new Person();
//设置person属性
ObjectMapper mapper = new ObjectMapper();


System.out.println(mapper.writeValueAsString(person));


激活美化的方式,同样可以是2.1和2.2介绍的方式。

4.包依赖

序列化为xml依赖:

  • jackson-databind
  • jackson-core
  • jackson-dataformat-xml

序列化为json依赖:

  • jackson-databind
  • jackson-core
<dependency><groupId>com.fasterxml.jackson.dataformat</groupId><artifactId>jackson-dataformat-xml</artifactId><version>2.8.2</version></dependency><dependency><groupId>com.fasterxml.jackson.core</groupId><artifactId>jackson-databind</artifactId><version>2.8.2</version></dependency><dependency><groupId>com.fasterxml.jackson.core</groupId><artifactId>jackson-core</artifactId><version>2.8.2</version></dependency>