README.md

Externalizor

Fast and compact serialization of Java object.

• Concrete Collections (Map, Set, Vector, List) with compression/decompression using Snappy
• Primitive types: int, long, short, double, float, boolean, char, byte, enum
• Primitive array: with compression/decompression using Snappy
• Time types: Date, LocalDate, LocalTime, LocalDateTime, Instant, Duration, Period, MonthDay, Year
• Other types are serialized using Java's default serialization

Usage

Use the provided static methods to serialize and/or deserialize your object(s). There is two ways:

• Raw serialization: the fastest
• Compressed serialization: slower but more compact

Raw serialization (fastest)

The serialization used our Snappy based specialized compressors.

import java.io.*;
import com.qwazr.externalizor.Externalizor;

public class FastSerialization {

    public FastSerialization() {

        MyClass object = new MyClass();
        byte[] bytes;
        
        // Serialization
        
        try (ByteArrayOutputStream output = new ByteArrayOutputStream()) {
            Externalizor.serializeRaw(object, output);
            bytes = output.toByteArray();
        }
        
        // Deserialization
        
        try (ByteArrayInputStream input = new ByteArrayInputStream(bytes)) {
            MyClass object = Externalizor.deserializeRaw(input);
        }
    }
 }

Compressed serialization (slower but more compact)

In addition of the specialized compression (snappy) a GZIP compression is used on the final serialized stream (slower but more compact).

import java.io.*;
import com.qwazr.externalizor.Externalizor;

public class CompactSerialization {

    public CompactSerialization() {

        MyClass object = new MyClass();
        byte[] bytes;
        
        // Serialization
        
        try (ByteArrayOutputStream input = new ByteArrayOutputStream()) {
            Externalizor.serialize(object, output);
            bytes = output.toByteArray();
        }
        
        // Deserialization
        
        try (ByteArrayInputStream input = new ByteArrayInputStream(bytes)) {
            object = Externalizor.deserialize(input);
        }
    }
}

Maven dependency

In Maven's central repository: central.maven.org/maven2/com/qwazr/externalizor

Add the following dependency to your pom.xml:

<dependency>
    <groupId>com.qwazr</groupId>
    <artifactId>externalizor</artifactId>
    <version>1.3.2</version>
</dependency>

Benchmark

The code of the benchmark is here: BenchmarkTest

• Serialization raw: Default Java serialization without compression.
• Serialization compressed: Default Java serialization with Gzip compression.
• Externalizor raw: Using Externalizor without compression.
• Externalizor compressed: Using Externalizor with Gzip compression.

Average size of the serialized objects

Bytes sizes. Smaller is better.

Serialization/Deserialization rate

Number of serialization and deserialization per seconds. Bigger is better.

Issues

Post bug reports or feature request to the Issue Tracker: https://github.com/qwazr/externalizor/issues

Open source license

Apache2 license