java中使用jackson处理json

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import java.util.List;
public class Student {
private int age;
private String name;
private String sex;
private List<Integer> scores;
public Student() {
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getSex() {
return sex;
}
public void setSex(String sex) {
this.sex = sex;
}
public List<Integer> getScores() {
return scores;
}
public void setScores(List<Integer> scores) {
this.scores = scores;
}
}

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public static void main(String[] args) throws IOException {
ObjectMapper om=new ObjectMapper();
Student student=new Student();
student.setAge(10);
student.setName("张三");
student.setSex("男");
student.setScores(Arrays.asList(10,20,30));
//讲JavaBean 转换为一个json对象
String studentJson = om.writeValueAsString(student);
System.out.println(studentJson);
System.out.println("----------我是一条分割线----------");
//将一个json对象转换为JavaBean
Student student1= om.readValue(studentJson,Student.class);
System.out.println(student1.getName());
System.out.println(student1.getAge());
System.out.println(student1.getScores());
System.out.println("----------我是一条分割线----------");
//获取json的数据
JsonNode jd= om.readTree(studentJson);
System.out.println(jd.get("name").asText());
System.out.println(jd.get("age"));
System.out.println(jd.get("scores"));
System.out.println("----------我是一条分割线----------");
String path = JsonTest.class.getClassLoader().getResource("student.json").getPath();
File fileJson=new File(path);
List<Student> list=om.readValue(fileJson, new TypeReference<List<Student>>(){});
for (Student student2: list) {
System.out.println(student2.getAge());
System.out.println(student2.getName());
System.out.println(student2.getScores());
}
}

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[
{
"age": 15,
"name": "张三",
"sex": "男",
"scores":[10,80,90]
},
{
"age": 16,
"name": "李四",
"sex": "女",
"scores":[100,99,88]
}
]