Introduction to the technical principles of the Kryo framework in the Java library
The KRYO framework is a fast, high -performance Java serialization framework that can convert the Java object into byte streaming to use it during network transmission or storage.This article will introduce the technical principles of the KRYO framework, including the underlying mechanism and use examples.
1. Technical principles
Kryo uses the ASM library -based bytecode operation to achieve efficient Java object serialization and derivativeization.Its technical principles can be divided into the following aspects:
1. Register
Before serialization and desertification, you need to register the Java class to be processed.Kryo uses a registry to manage these classes, including the field information and serialized and back -sequentialized processors.Once the class is registered, Kryo will be able to create the corresponding bytecode processor for it.
2. Bytecode generation
KRYO uses ASM library to form bytecode processor to process objects to be serialized or deeper.This method can avoid using the Java reflection mechanism, thereby improving performance.The ASM library provides a high -end API to operate the byte code, and Kryo uses it to generate a customized bytecode processor.In the process of bytecode generating, Kryo will generate corresponding serialization and dependent logic according to the field information of the object.
3. Serialization
During the serialization process, Kryo will convert the Java object into byte flow based on the registered category information and field information.It traverses the field of the object and writes the corresponding data into the byte running according to the field type.Kryo has a predefined processor for the basic types of Java and the commonly used data structures (such as List, MAP, etc.), so these situations can be effectively handled.
4. Reverse serialization
In the process of deepertization, Kryo will convert the byte flow to the Java object according to the byte flow and registered information.Kryo will read the data in the byte flow in the order of serialization, and restore the data as the corresponding Java object according to the field type.The processor generated by bytecode, Kryo can directly operate the content of the bytes of the bytes, thereby improving the efficiency of the rottenization.
2. Example code
Here are a sample code that uses the KRYO framework for serialization and back -sequentialization:
// Create Kryo object
Kryo kryo = new Kryo();
// Register
kryo.register(User.class);
// Serialization
User user = new User("Alice", 25);
byte[] serializedData = null;
try (ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
Output output = new Output(outputStream)) {
kryo.writeObject(output, user);
output.flush();
serializedData = outputStream.toByteArray();
} catch (IOException e) {
e.printStackTrace();
}
// Reverse serialization
User deserializedUser = null;
try (Input input = new Input(new ByteArrayInputStream(serializedData))) {
deserializedUser = kryo.readObject(input, User.class);
} catch (IOException e) {
e.printStackTrace();
}
System.out.println ("Original object:" + user);
System.out.println ("" Objects after the dependentization: " + DeserializedUser);
In the above code, we first created a Kryo object and registered the serialized User class.Then, we created a User object and serialized it into byte flow.Finally, we transformed the byte flow into a new User object.By printing primitive objects and desertified objects, we can verify the accuracy of serialization and deepertine.
Summarize:
The KRYO framework uses bytecode generation and efficient serialized processor to achieve fast and high -performance Java object serialization and derivativeization.It avoids the performance loss of the reflection mechanism and is suitable for efficient serialized operations on the Java object in network transmission or persistence storage.
