Java将对象序列化成为JSON格式、JSON格式反序列化为Java对象

我就是我 2024-02-18 23:13 75阅读 0赞

**摘要**：Java将对象序列化成为JSON格式、JSON格式反序列化为Java对象。

#### 一：引入jackson的依赖： ####

<dependency>
      <groupId>org.codehaus.jackson</groupId>
      <artifactId>jackson-mapper-asl</artifactId>
      <version>1.9.12</version>
    </dependency>
    <dependency>
      <groupId>org.codehaus.jackson</groupId>
      <artifactId>jackson-core-asl</artifactId>
      <version>1.9.12</version>
    </dependency>

#### 二：编写实体对象类Employee ####

package cn.micai.base.io;
    
    import java.io.Serializable;
    
    /**
     * 描述：
     * <p>
     *
     *     transient使用小结
     *     1.一旦变量被transient修饰，变量将不再是对象持久化的一部分，该变量内容在序列化后无法获得访问。
     *     2.transient关键字只能修饰变量，而不能修饰方法和类。注意，本地变量是不能被transient关键字修饰的。变量如果是用户自定义类变量，则该类需要实现Serializable接口。
     *     3.被transient关键字修饰的变量不再能被序列化，一个静态变量不管是否被transient修饰，均不能被序列化。
     *
     * @author: 赵新国
     * @date: 2018/6/7 12:10
     */
    public class Employee implements Serializable {
    
        private static final long serialVersionUID = 1L;
        private int employeeId;
        private String employeeName;
        /**
         * 使用transient关键字，表示该字段不序列化
         */
        private transient String department;
    
        public int getEmployeeId() {
            return employeeId;
        }
        public void setEmployeeId(int employeeId) {
            this.employeeId = employeeId;
        }
        public String getEmployeeName() {
            return employeeName;
        }
        public void setEmployeeName(String employeeName) {
            this.employeeName = employeeName;
        }
        public String getDepartment() {
            return department;
        }
        public void setDepartment(String department) {
            this.department = department;
        }
    
        @Override
        public String toString() {
            return "Employee{" +
                    "employeeId=" + employeeId +
                    ", employeeName='" + employeeName + '\'' +
                    ", department='" + department + '\'' +
                    '}';
        }
    }

#### 三：编写使用jackson-all.1.7.6.jar工具包实现将对象序列化为JSON格式、JSON格式反序列化为对象的类 ####

package cn.micai.base.io;
    
    import org.codehaus.jackson.JsonFactory;
    import org.codehaus.jackson.JsonGenerator;
    import org.codehaus.jackson.map.ObjectMapper;
    
    import java.io.IOException;
    import java.io.StringWriter;
    
    /**
     * @Auther: zhaoxinguo
     * @Date: 2018/8/23 12:03
     * @Description: 使用jackson-all.1.7.6.jar工具包实现将对象序列化为JSON格式、JSON格式反序列化为对象
     */
    public class JacksonAllSerializeDeserializeMain {
    
        /**
         * 将Java对象employee序列化成为JSON格式
         * @param employee
         * @return
         */
        public static String serialize(Employee employee){
            // JSON对象序列化
            String employeeJson = null;
            try {
                ObjectMapper objectMapper = new ObjectMapper();
                StringWriter stringWriter = new StringWriter();
                JsonGenerator jsonGenerator = new JsonFactory().createJsonGenerator(stringWriter);
                objectMapper.writeValue(jsonGenerator, employee);
                jsonGenerator.close();
                employeeJson = stringWriter.toString();
            } catch (IOException e) {
                e.printStackTrace();
            }
            return employeeJson;
        }
    
        /**
         * 将JSON格式反序列化为employee对象
         * @param employeeJson
         * @return
         */
        public static Employee deserialize(String employeeJson) {
            try {
                ObjectMapper objectMapper = new ObjectMapper();
                return objectMapper.readValue(employeeJson, Employee.class);
            } catch (IOException e) {
                e.printStackTrace();
            }
            return null;
        }
    
        public static void main(String [] args) {
    
            Employee employee = new Employee();
            employee.setEmployeeId(1);
            employee.setEmployeeName("赵新国");
            employee.setDepartment("软件工程师");
            // 序列化
            String serialize = serialize(employee);
            System.out.println(serialize);
            // 反序列化
            Employee deserialize = deserialize(serialize);
            System.out.println(deserialize);
    
        }
    
    }

#### 四：运行结果： ####

![70][]

[70]: https://image.dandelioncloud.cn/pgy_files/images/2024/01/29/0b86ff5fcb114fe39b759d448d260d64.png