Prototype pattern SerializationUtils in Apache Commons Lang library
Apache Commons Lang is a Java class library that provides many tool classes and practical methods for enhancing the Java foundation class library. Among them, the Prototype pattern SerializationUtils is one of the important functions in the library.
Prototype pattern is a creative design pattern, which creates new objects by copying (cloning) the original objects, rather than creating them through constructors. By using the Prototype pattern, you can avoid directly calling the constructor to create new objects and improve the efficiency of object creation.
In the Apache Commons Lang library, the SerializationUtils class provides methods for deep cloning of objects (through serialization and deserialization). Specifically, it achieves cloning by writing objects to a byte stream, then reading and creating a new object from the byte stream.
The following is the complete source code of the SerializationUtils class in the Apache Commons Lang library:
import java.io.*;
public class SerializationUtils {
public static <T> T clone(final T object) {
if (object == null) {
return null;
}
final byte[] objectData = serialize(object);
return deserialize(objectData);
}
@SuppressWarnings("unchecked")
public static <T> T deserialize(final byte[] objectData) {
if (objectData == null) {
return null;
}
try (ByteArrayInputStream bais = new ByteArrayInputStream(objectData)) {
try (ObjectInputStream ois = new ObjectInputStream(bais)) {
return (T) ois.readObject();
}
}Catch (IOException | ClassNotFoundException e){
throw new SerializationException(e);
}
}
public static <T extends Serializable> byte[] serialize(final T obj) {
if (obj == null) {
return null;
}
try (ByteArrayOutputStream baos = new ByteArrayOutputStream()) {
try (ObjectOutputStream oos = new ObjectOutputStream(baos)) {
oos.writeObject(obj);
return baos.toByteArray();
}
} catch (IOException e) {
throw new SerializationException(e);
}
}
}
Summary:
The Prototype pattern SerializationUtils in the Apache Commons Lang library provides a method for deep cloning of objects. It implements cloning by serializing and deserializing objects, and provides methods such as clone, serialize, and deserialize for use. The clone method of the SerializationUtils class makes it easy to clone objects without directly calling the constructor. This method not only improves the efficiency of object creation, but also maintains the independence between objects. It is a very convenient and practical Prototype pattern implementation.
