Spring boot 項目集成Redisson做分布式鎖的時候，拋異常 NoClassDefFoundError: Lorg/nustaq/serialization/FSTConfiguration，本文總結一下解決方案。
問題背景
Spring boot 項目集成Redisson配置分布式鎖的時候，提示如下異常：
Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.redisson.api.RedissonClient]: Factory method 'redisson' threw exception; nested exception is java.lang.NoClassDefFoundError: Lorg/nustaq/serialization/FSTConfiguration;
問題分析
缺少fst依賴導致的，添加maven依賴
<dependency>
<groupId>de.ruedigermoeller</groupId>
<artifactId>fst</artifactId>
<version>2.57</version>
</dependency>
問題延伸
fst是什么？FST fast-serialization 是重新實現的 Java 快速對象序列化的開發包。序列化速度更快（2-10倍）、體積更小，而且兼容 JDK 原生的序列化。要求 JDK 1.7 支持。
// ! reuse this Object, it caches metadata. Performance degrades massively
// if you create a new Configuration Object with each serialization !
static FSTConfiguration conf = FSTConfiguration.createDefaultConfiguration();
...
public MyClass myreadMethod(InputStream stream) throws IOException, ClassNotFoundException
{
FSTObjectInput in = conf.getObjectInput(stream);
MyClass result = in.readObject(MyClass.class);
// DON'T: in.close(); here prevents reuse and will result in an exception
stream.close();
return result;
}
public void mywriteMethod( OutputStream stream, MyClass toWrite ) throws IOException
{
FSTObjectOutput out = conf.getObjectOutput(stream);
out.writeObject( toWrite, MyClass.class );
// DON'T out.close() when using factory method;
out.flush();
stream.close();
}