0x01 建立要轉換的類和主函式

注意這裡一定要實現序列化

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

0x02 物件和位元組陣列互轉

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物件轉位元組陣列\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 ("位元組陣列還原物件\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;
  }
}

執行結果

java class物件轉位元組陣列

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

位元組陣列還原物件

test

補充知識：java物件與byte[]陣列之間的相互轉化，壓縮解壓縮操作

下面介紹一下java物件之間和byte[]陣列之間的相互轉化。並對byte[]資料進行壓縮操作。java物件轉化為byte[]陣列可用於redis中實現快取。（這裡暫不做介紹）.話不多說直接開例項：

首先我們建立一個java物件：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;
  }
}

下面演示對person物件的轉換：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物件的byte陣列
      byte[] personByteArray = bos.toByteArray();
      System.out.println("before compress:"+personByteArray.length);
      //將byte資料壓縮
      byte[] zipPersonByteArray = compress(personByteArray);
      System.out.println("after compress:"+zipPersonByteArray.length);
      closeStream(oos);
      closeStream(bos);
      //從byte陣列中還原person物件
      ByteArrayInputStream bin=new ByteArrayInputStream(personByteArray);
      ObjectInputStream ois=new ObjectInputStream(bin);
      Person restorePerson = (Person) ois.readObject();
      System.out.println(restorePerson);
      closeStream(ois);
      closeStream(bin);
      //從壓縮的byte陣列中還原person物件
      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   關閉資料流
   * @param oStream    
   *   
   */
  public static void closeStream(Closeable oStream){
    if(null!=oStream){
      try {
        oStream.close();
      } catch (IOException e) {
        oStream=null;//賦值為null,等待垃圾回收
        e.printStackTrace();
      }
    }
  }

  /**
   *   
   * @description   將byte 陣列壓縮
   * @param bt
   * @return   
   */
  public static byte[] compress(byte[] bt){
    //將byte資料讀入檔案流
    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   解壓縮byte陣列
   * @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,temp);
      }
    } catch (Exception e) {
      e.printStackTrace();
      return null;
    }finally{
      closeStream(byteAos);
      closeStream(gzipIn);
      closeStream(byteArrayIn);
    }
    return byteAos.toByteArray();
  }
}

上面的示例顯示了：java物件到byte[]資料的轉化；

byte[]資料的壓縮和解壓縮操作；

byte[]資料還原java物件的操作；

執行結果：

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

以上這篇JAVA物件和位元組陣列互轉操作就是小編分享給大家的全部內容了，希望能給大家一個參考，也希望大家多多支援我們。