Java内置的实现序列化、反序列化、案例

摘要：Java内置的实现序列化、反序列化、案例

一：创建Maven工程，编写Java内置的序列化，反序列化方法

package cn.micai.base.io;

import java.io.*;

/**
 * @Auther: zhaoxinguo
 * @Date: 2018/8/23 10:48
 * @Description: Java内置的实现序列化、反序列化
 */
public class JavaSerializeDeserializeMain {

    /**
     * Java内置的实现序列化
     * @param employee
     * @return
     * @throws IOException
     */
    public static byte[] serialize(Employee employee){
        // 定义一个字节数组输出流
        ByteArrayOutputStream byteArrayOutputStream = null;
        // 对象输出流
        ObjectOutputStream objectOutputStream = null;
        try {
            byteArrayOutputStream = new ByteArrayOutputStream();
            objectOutputStream = new ObjectOutputStream(byteArrayOutputStream);
            // 将对象写入到字节数组输出，进行序列化
            objectOutputStream.writeObject(employee);
            return byteArrayOutputStream.toByteArray();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                byteArrayOutputStream.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
            try {
                objectOutputStream.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        return null;
    }

    /**
     * Java内置的实现反序列化
     * @param employeeArray
     * @return
     */
    public static Employee deserialize(byte[] employeeArray) {
        // 定义字节数组输入流
        ByteArrayInputStream byteArrayInputStream = null;
        // 执行反序列化，从流中读取对象
        ObjectInputStream objectInputStream = null;
        try {
            byteArrayInputStream = new ByteArrayInputStream(employeeArray);
            objectInputStream = new ObjectInputStream(byteArrayInputStream);
            return (Employee) objectInputStream.readObject();
        } catch (IOException e) {
            e.printStackTrace();
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        } finally {
            try {
                byteArrayInputStream.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
            try {
                objectInputStream.close();
            } 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
        byte[] serialize = serialize(employee);
        System.out.println(serialize);
        // 反序列化
        Employee deserialize = deserialize(serialize);
        System.out.println(deserialize.toString());

    }

}

二：编写Employee对象

package cn.micai.base.io;

import java.io.Serializable;

/**
 * 描述：
 * 

 *
 *     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：测试结果

温馨提示：这里反序列化以后，department字段为空，是因为在Employee对象里面对这个字段加了transient修饰符，该修饰符的作用就是该字段不序列化，所以反序列化后，该字段为空是正常的。