另一个有趣的方法来自com.fasterxml.jackson.databind.ObjectMapper

byte[] data = new ObjectMapper().writeValueAsBytes(JAVA_OBJECT_HERE)

Maven的依赖

<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-databind</artifactId>
</dependency>

如果你使用spring，在spring-core中有一个util类可用。你可以简单地

import org.springframework.util.SerializationUtils;

byte[] bytes = SerializationUtils.serialize(anyObject);
Object object = SerializationUtils.deserialize(bytes);

另一个有趣的方法来自com.fasterxml.jackson.databind.ObjectMapper

byte[] data = new ObjectMapper().writeValueAsBytes(JAVA_OBJECT_HERE)

Maven的依赖

<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-databind</artifactId>
</dependency>

准备要发送的字节数组:

ByteArrayOutputStream bos = new ByteArrayOutputStream();
ObjectOutputStream out = null;
try {
  out = new ObjectOutputStream(bos);   
  out.writeObject(yourObject);
  out.flush();
  byte[] yourBytes = bos.toByteArray();
  ...
} finally {
  try {
    bos.close();
  } catch (IOException ex) {
    // ignore close exception
  }
}

从字节数组创建一个对象:

ByteArrayInputStream bis = new ByteArrayInputStream(yourBytes);
ObjectInput in = null;
try {
  in = new ObjectInputStream(bis);
  Object o = in.readObject(); 
  ...
} finally {
  try {
    if (in != null) {
      in.close();
    }
  } catch (IOException ex) {
    // ignore close exception
  }
}

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 {

    }




}

我也推荐使用SerializationUtils工具。我想对@Abilash的错误评论做一个调整。SerializationUtils.serialize()方法不限制为1024字节，这与这里的另一个答案相反。

public static byte[] serialize(Object object) {
    if (object == null) {
        return null;
    }
    ByteArrayOutputStream baos = new ByteArrayOutputStream(1024);
    try {
        ObjectOutputStream oos = new ObjectOutputStream(baos);
        oos.writeObject(object);
        oos.flush();
    }
    catch (IOException ex) {
        throw new IllegalArgumentException("Failed to serialize object of type: " + object.getClass(), ex);
    }
    return baos.toByteArray();
}

乍一看，您可能认为新的ByteArrayOutputStream(1024)只允许固定的大小。但是如果你仔细观察ByteArrayOutputStream，你会发现流在必要时还会增长:

该类实现了一个输出流，其中数据为 写入字节数组。缓冲区自动作为数据增长 被写入。 可以使用toByteArray()和 toString ()。