JAVA对象和字节数组互转操作

0x01 创建要转换的类和主函数

注意这里一定要实现序列化

package day1;
import java.io.Serializable;
public class Test360 implements Serializable {
   @Override
   public String toString() {
       return "Test360{" +
           "name='" + name + '\'' +
           '}';
   }

String name="test";
}

0x02 对象和字节数组互转

package day1;
import sun.jvm.hotspot.utilities.Assert;
import java.io.*;

public class arreytobytes  {
 public static void main(String[] args) throws Exception {
   Test360 test =new Test360();
   System.out.print ( "java class对象转字节数组\n" );
   byte[] bufobject = getBytesFromObject(test);
   for(int i=0 ; i<bufobject.length ; i++) {
     System.out.print(bufobject[i] + ",");
   }
   System.out.println ("\n");
   System.out.print ("字节数组还原对象\n");
   Object object1 = null;
   object1=deserialize(bufobject);
   Test360 t1 =(Test360)object1;
   System.out.println (t1.name);
 }
 public static byte[] getBytesFromObject(Serializable obj) throws Exception {
   if (obj == null) {
     return null;
   }
   ByteArrayOutputStream bo = new ByteArrayOutputStream();
   ObjectOutputStream oos = new ObjectOutputStream(bo);
   oos.writeObject(obj);
   return bo.toByteArray();
 }
 public static Object deserialize(byte[] bytes) {
   Object object = null;
   try {
     ByteArrayInputStream bis = new ByteArrayInputStream(bytes);//
     ObjectInputStream ois = new ObjectInputStream(bis);
       object = ois.readObject();
     ois.close();
     bis.close();
   } catch (IOException ex) {
     ex.printStackTrace();
   } catch (ClassNotFoundException ex) {
     ex.printStackTrace();
   }
   return object;
 }
}

运行结果

java class对象转字节数组

-84,-19,0,5,115,114,0,12,100,97,121,49,46,84,101,115,116,51,54,48,76,-69,81,12,-51,122,126,-123,2,0,0,120,112,

字节数组还原对象

test

补充知识：java对象与byte[]数组之间的相互转化，压缩解压缩操作

下面介绍一下java对象之间和byte[]数组之间的相互转化。并对byte[]数据进行压缩操作。java对象转化为byte[]数组可用于redis中实现缓存。（这里暂不做介绍）.话不多说直接开实例：

首先我们创建一个java对象：Person.java

public class Person implements Serializable{
 private String userName;
 private String password;
 private String phone;
 private String email;
 private String sex;
 private String age;

public Person(){}

public Person(String userName, String password, String phone, String email,
     String sex, String age) {
   super();
   this.userName = userName;
   this.password = password;
   this.phone = phone;
   this.email = email;
   this.sex = sex;
   this.age = age;
 }
 @Override
 public String toString() {
   return "Person [userName=" + userName + ", password=" + password
       + ", phone=" + phone + ", email=" + email + ", sex=" + sex
       + ", age=" + age + "]";
 }
 public String getUserName() {
   return userName;
 }
 public void setUserName(String userName) {
   this.userName = userName;
 }
 public String getPassword() {
   return password;
 }
 public void setPassword(String password) {
   this.password = password;
 }
 public String getPhone() {
   return phone;
 }
 public void setPhone(String phone) {
   this.phone = phone;
 }
 public String getEmail() {
   return email;
 }
 public void setEmail(String email) {
   this.email = email;
 }
 public String getSex() {
   return sex;
 }
 public void setSex(String sex) {
   this.sex = sex;
 }
 public String getAge() {
   return age;
 }
 public void setAge(String age) {
   this.age = age;
 }
}

下面演示对person对象的转换：Object2ByteArray.java

public class Object2ByteArray {
 public static void main(String[] args) {
   try {
     Person person=new Person("userName", "password", "phone", "email", "sex", "age");
     System.out.println("person:"+person);
     ByteArrayOutputStream bos=new ByteArrayOutputStream();
     ObjectOutputStream oos=new ObjectOutputStream(bos);
     oos.writeObject(person);
     //得到person对象的byte数组
     byte[] personByteArray = bos.toByteArray();
     System.out.println("before compress:"+personByteArray.length);
     //将byte数据压缩
     byte[] zipPersonByteArray = compress(personByteArray);
     System.out.println("after compress:"+zipPersonByteArray.length);
     closeStream(oos);
     closeStream(bos);
     //从byte数组中还原person对象
     ByteArrayInputStream bin=new ByteArrayInputStream(personByteArray);
     ObjectInputStream ois=new ObjectInputStream(bin);
     Person restorePerson = (Person) ois.readObject();
     System.out.println(restorePerson);
     closeStream(ois);
     closeStream(bin);
     //从压缩的byte数组中还原person对象
     byte[] unCompressByte = unCompress(zipPersonByteArray);
     ByteArrayInputStream zipBin=new ByteArrayInputStream(unCompressByte);
     ObjectInputStream zipOis=new ObjectInputStream(zipBin);
     Person zipBytePerson=(Person) zipOis.readObject();
     System.out.println("compress person:"+zipBytePerson.toString());
     closeStream(zipOis);
     closeStream(zipBin);
   } catch (Exception e) {
     e.printStackTrace();
   }

}

/**
  *  
  * @description   关闭数据流
  * @param oStream    
  *  
  */
 public static void closeStream(Closeable oStream){
   if(null!=oStream){
     try {
       oStream.close();
     } catch (IOException e) {
       oStream=null;//赋值为null,等待垃圾回收
       e.printStackTrace();
     }
   }
 }

/**
  *  
  * @description   将byte 数组压缩
  * @param bt
  * @return  
  */
 public static byte[] compress(byte[] bt){
   //将byte数据读入文件流
   ByteArrayOutputStream bos=null;
   GZIPOutputStream gzipos=null;
   try {
     bos=new ByteArrayOutputStream();
     gzipos=new GZIPOutputStream(bos);
     gzipos.write(bt);
   } catch (Exception e) {
     e.printStackTrace();
   }finally{
     closeStream(gzipos);
     closeStream(bos);
   }
   return bos.toByteArray();
 }

/**
  *  
  * @description   解压缩byte数组
  * @param bt
  * @return  
  */
 public static byte[] unCompress(byte[] bt){
   //byte[] unCompress=null;
   ByteArrayOutputStream byteAos=null;
   ByteArrayInputStream byteArrayIn=null;
   GZIPInputStream gzipIn=null;
   try {
     byteArrayIn=new ByteArrayInputStream(bt);
     gzipIn=new GZIPInputStream(byteArrayIn);
      byteAos=new ByteArrayOutputStream();
     byte[] b=new byte[4096];
     int temp = -1;
     while((temp=gzipIn.read(b))>0){
       byteAos.write(b, 0, temp);
     }
   } catch (Exception e) {
     e.printStackTrace();
     return null;
   }finally{
     closeStream(byteAos);
     closeStream(gzipIn);
     closeStream(byteArrayIn);
   }
   return byteAos.toByteArray();
 }
}

上面的示例显示了：java对象到byte[]数据的转化；

byte[]数据的压缩和解压缩操作；

byte[]数据还原java对象的操作；

运行结果：

person:Person [userName=userName, password=password, phone=phone, email=email, sex=sex, age=age]
before compress:189
after compress:156
Person [userName=userName, password=password, phone=phone, email=email, sex=sex, age=age]
compress person:Person [userName=userName, password=password, phone=phone, email=email, sex=sex, age=age]

来源：https://blog.csdn.net/qq_38376348/article/details/107021408