假设我有一个可序列化的类AppMessage。

我想通过套接字将它作为字节[]传输到另一台机器,在那里它从接收到的字节重建。

我怎么才能做到呢?


当前回答

这只是一个被接受的答案的优化代码形式,以防有人想在生产中使用它:

    public static void byteArrayOps() throws IOException, ClassNotFoundException{

    String str="123";
     byte[] yourBytes = null;

    // Convert to byte[]

    try(ByteArrayOutputStream bos = new ByteArrayOutputStream();
            ObjectOutputStream out =  new ObjectOutputStream(bos);) {


      out.writeObject(str);
      out.flush();
      yourBytes = bos.toByteArray();

    } finally {

    }

    // convert back to Object

    try(ByteArrayInputStream bis = new ByteArrayInputStream(yourBytes);
            ObjectInput in = new ObjectInputStream(bis);) {

      Object o = in.readObject(); 

    } finally {

    }




}

其他回答

Java 8+的代码示例:

public class Person implements Serializable {

private String lastName;
private String firstName;

public Person() {
}

public Person(String firstName, String lastName) {
    this.firstName = firstName;
    this.lastName = lastName;
}

public void setFirstName(String firstName) {
    this.firstName = firstName;
}

public String getFirstName() {
    return firstName;
}

public String getLastName() {
    return lastName;
}

public void setLastName(String lastName) {
    this.lastName = lastName;
}

@Override
public String toString() {
    return "firstName: " + firstName + ", lastName: " + lastName;
}
}


public interface PersonMarshaller {
default Person fromStream(InputStream inputStream) {
    try (ObjectInputStream objectInputStream = new ObjectInputStream(inputStream)) {
        Person person= (Person) objectInputStream.readObject();
        return person;
    } catch (IOException | ClassNotFoundException e) {
        System.err.println(e.getMessage());
        return null;
    }
}

default OutputStream toStream(Person person) {
    try (OutputStream outputStream = new ByteArrayOutputStream()) {
        ObjectOutput objectOutput = new ObjectOutputStream(outputStream);
        objectOutput.writeObject(person);
        objectOutput.flush();
        return outputStream;
    } catch (IOException e) {
        System.err.println(e.getMessage());
        return null;
    }

}

}

我想通过套接字将它作为字节[]传输到另一台机器

// When you connect
ObjectOutputStream oos = new ObjectOutputStream(socket.getOutputStream());
// When you want to send it
oos.writeObject(appMessage);

从接收到的字节重新构建。

// When you connect
ObjectInputStream ois = new ObjectInputStream(socket.getInputStream());
// When you want to receive it
AppMessage appMessage = (AppMessage)ois.readObject();

可以通过SerializationUtils完成,通过ApacheUtils的serialize & deserialize方法将对象转换为字节[],反之亦然,如@uris answer中所述。

通过序列化将一个对象转换为字节[]:

byte[] data = SerializationUtils.serialize(object);

通过反序列化将byte[]转换为object::

Object object = (Object) SerializationUtils.deserialize(byte[] data)

点击下载org-apache-commons-lang.jar的链接

通过点击整合.jar文件:

FileName ->打开Medule Settings ->选择你的模块-> Dependencies ->添加Jar文件,完成。

希望这能有所帮助。

如果你使用Java >= 7,你可以使用try和资源改进接受的解决方案:

private byte[] convertToBytes(Object object) throws IOException {
    try (ByteArrayOutputStream bos = new ByteArrayOutputStream();
         ObjectOutputStream out = new ObjectOutputStream(bos)) {
        out.writeObject(object);
        return bos.toByteArray();
    } 
}

反过来说:

private Object convertFromBytes(byte[] bytes) throws IOException, ClassNotFoundException {
    try (ByteArrayInputStream bis = new ByteArrayInputStream(bytes);
         ObjectInputStream in = new ObjectInputStream(bis)) {
        return in.readObject();
    } 
}

如果你想要一个不错的无依赖复制粘贴解决方案。获取下面的代码。

例子

MyObject myObject = ...

byte[] bytes = SerializeUtils.serialize(myObject);
myObject = SerializeUtils.deserialize(bytes);

import java.io.*;

public class SerializeUtils {

    public static byte[] serialize(Serializable value) throws IOException {
        ByteArrayOutputStream out = new ByteArrayOutputStream();

        try(ObjectOutputStream outputStream = new ObjectOutputStream(out)) {
            outputStream.writeObject(value);
        }

        return out.toByteArray();
    }

    public static <T extends Serializable> T deserialize(byte[] data) throws IOException, ClassNotFoundException {
        try(ByteArrayInputStream bis = new ByteArrayInputStream(data)) {
            //noinspection unchecked
            return (T) new ObjectInputStream(bis).readObject();
        }
    }
}