Java web学习之路-序列化和反序列化

/**
* 写入对象内容
*/
private void writeObject(java.io.ObjectOutputStream out)

import java.io.Serializable;

//创建测试类，注意要实现Serializable接口
public class Employee implements Serializable{
public String name;
public String identify;
public void mailCheck()
{
System.out.println("This is the "+this.identify+" of our company");
}
}

//引入必要的java包文件
import java.io.*;

//主类
public class SerializableStep{
//测试主类
public static void main(String [] args)
{
Employee e = new Employee();
e.name = "l1nk3r";
e.identify = "l1nk3r";
try
{
// 打开一个文件输入流
FileOutputStream fileOut =
new FileOutputStream("/Users/l1nk3r/Desktop/employee1.obj");
// 建立对象输入流
ObjectOutputStream out = new ObjectOutputStream(fileOut);
//输出反序列化对象
out.writeObject(e);
out.close();
fileOut.close();
System.out.printf("Serialized data is saved in /Users/l1nk3r/Desktop/employee1.obj");
}catch(IOException i)
{
i.printStackTrace();
}
}
}

//ObjectSerTest1.java
import java.io.*;

class Student1 implements Serializable {
private static final long serialVersionUID = 1L;
private String name;
private transient String password;                 //transient关键字
private static int count = 0;                      //静态变量

public Student1(String name, String password) {
System.out.println("调用Student的带参的构造方法");
this.name = name;
this.password = password;
count++;
}

public String toString() {
return "人数: " + count + " 姓名: " + name + " 密码: " + password;
}
}

public class ObjectSerTest1 {
public static void main(String args[]) {
try {
FileOutputStream fos = new FileOutputStream("test.obj");
ObjectOutputStream oos = new ObjectOutputStream(fos);
Student1 s1 = new Student1("张三", "12345");
Student1 s2 = new Student1("王五", "54321");
oos.writeObject(s1);
oos.writeObject(s2);
oos.close();
} catch (IOException e) {
e.printStackTrace();
} 
}
}

//Test.java
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;

public class Test{
public static void main(String args[]){ 
try {
FileInputStream fis = new FileInputStream("test.obj");
ObjectInputStream ois = new ObjectInputStream(fis);
Student1 s3 = (Student1) ois.readObject();
Student1 s4 = (Student1) ois.readObject();
System.out.println(s3);
System.out.println(s4);
ois.close();
} catch (IOException e) {
e.printStackTrace();
} catch (ClassNotFoundException e1) {
e1.printStackTrace();
}
}
}

public interface Externalizable extends java.io.Serializable {
/**
* The object implements the writeExternal method to save its contents
* by calling the methods of DataOutput for its primitive values or

void writeExternal(ObjectOutput out) throws IOException;

void readExternal(ObjectInput in) throws IOException, ClassNotFoundException;

//Person.java
/**
* 测试实体类
*/
class Person implements Externalizable{
private static final long serialVersionUID = 1L;
transient String userName;
String password;
String age;

/**
* 序列化操作的扩展类
*/
@Override
public void writeExternal(ObjectOutput out) throws IOException {
//增加一个新的对象
Date date=new Date();
out.writeObject(userName);
out.writeObject(password);
out.writeObject(date);
}

/**
* 反序列化的扩展类
*/
@Override
public void readExternal(ObjectInput in) throws IOException,
ClassNotFoundException {
//注意这里的接受顺序是有限制的哦，否则的话会出错的
// 例如上面先write的是A对象的话，那么下面先接受的也一定是A对象...
userName=(String) in.readObject();
password=(String) in.readObject();
SimpleDateFormat sdf=new SimpleDateFormat("yyyy-MM-dd");
Date date=(Date)in.readObject();       
System.out.println("反序列化后的日期为:"+sdf.format(date));

}
}

/**
* 读取对象内容
*/
private void readObject(java.io.ObjectInputStream in)

//引入必要的java包文件
import java.io.*;

public class unSerializableStep{
public static void main(String [] args)
{
Employee e = null;
try
{
// 打开一个文件输入流
FileInputStream fileIn = new FileInputStream("/Users/l1nk3r/Desktop/employee1.obj");
// 建立对象输入流
ObjectInputStream in = new ObjectInputStream(fileIn);
// 读取对象
e = (Employee) in.readObject();
in.close();
fileIn.close();
}catch(IOException i)
{
i.printStackTrace();
return;
}catch(ClassNotFoundException c)
{
System.out.println("Employee class not found");
c.printStackTrace();
return;
}
System.out.println("Deserialized Employee...");
System.out.println("Name: " + e.name);
System.out.println("This is the "+e.identify+" of our company");
}
}

//ObjectCalc.java
import java.io.IOException;
import java.io.Serializable;

class ObjectCalc implements Serializable{
public String name;
//重写readObject()方法
private void readObject(java.io.ObjectInputStream in) throws IOException, ClassNotFoundException{
//执行默认的readObject()方法
in.defaultReadObject();
//执行打开计算器程序命令
Runtime.getRuntime().exec("open /Applications/Calculator.app/");
}
}

//SerializableCalc.java
//引入必要的java包文件
import java.io.*;

public class SerializableCalc{
public static void main(String args[]) throws Exception{
//定义myObj对象
ObjectCalc myObj = new ObjectCalc();
myObj.name = "hi";
//创建一个包含对象进行反序列化信息的”object”数据文件
FileOutputStream fos = new FileOutputStream("/Users/l1nk3r/Desktop/object");
ObjectOutputStream os = new ObjectOutputStream(fos);
//writeObject()方法将myObj对象写入object文件
os.writeObject(myObj);
os.close();
}
}

//unSerializableCalc.java
//引入必要的java包文件
import java.io.*;

public class unSerializableCalc{
public static void main(String args[]) throws Exception{
//从文件中反序列化obj对象
FileInputStream fis = new FileInputStream("/Users/l1nk3r/Desktop/object");
ObjectInputStream ois = new ObjectInputStream(fis);
//恢复对象
ObjectCalc objectFromDisk = (ObjectCalc)ois.readObject();
System.out.println(objectFromDisk.name);
ois.close();
}
}

java.io.ObjectOutputStream  ->   writeObject()           //序列化操作
java.io.ObjectInputStream   ->   readObject()            //反序列化操作