# Usage

{% hint style="warning" %}
**This is the manual for older MicroStream versions (Version < 5.0).**

**The new documentation (Version >= 5.0) is located at:**

[https://docs.microstream.one/](https://docs.microstream.one/manual)
{% endhint %}

MicroStream's wrapper code generator generates following wrapper type for `PersistenceStoring`:

```java
public interface WrapperPersistenceStoring 
	extends Wrapper<PersistenceStoring>, PersistenceStoring
{
	@Override
	public default long store(final Object instance)
	{
		return this.wrapped().store(instance);
	}

	@Override
	public default long[] storeAll(final Object... instances)
	{
		return this.wrapped().storeAll(instances);
	}

	@Override
	public default void storeAll(final Iterable<?> instances)
	{
		this.wrapped().storeAll(instances);
	}

	@Override
	public default void storeSelfStoring(final SelfStoring storing)
	{
		this.wrapped().storeSelfStoring(storing);
	}
}
```

It is not an abstract class, but an interface, which extends the `Wrapper` interface of the *base* module, and the wrapped type itself. This offers you the most flexible way to use it in your application.

The `Wrapper` type is just a typed interface and an abstract implementation of itself.

{% code title="Wrapper.java" %}

```java
public interface Wrapper<W>
{
	public W wrapped();
	
	public abstract class Abstract<W> implements Wrapper<W>
	{
		private final W wrapped;

		protected Abstract(final W wrapped)
		{
			super();
			
			this.wrapped = wrapped;
		}
		
		@Override
		public final W wrapped()
		{
			return this.wrapped;
		}
	}
}
```

{% endcode %}

You can either implement the `Wrapper` interface and provide the wrapped instance via the `wrapped()` method, or you can extend the abstract class and hand over the wrapped instance to the super constructor.

Version with the abstract type:

```java
public class PersistenceStoringWithLogging 
	extends Wrapper.Abstract<PersistenceStoring>
	implements WrapperPersistenceStoring
{
	public PersistenceStoringWithLogging(final PersistenceStoring wrapped)
	{
		super(wrapped);
	}
	
	@Override
	public long store(Object instance)
	{
		Logger.getLogger(PersistenceStoring.class.getName())
			.info("Object stored: " + instance);
		
		return WrapperPersistenceStoring.super.store(instance);
	}
}
```

Or only the interface, then you have to provide the wrapped instance via `wrapped()`:

```java
public class PersistenceStoringWithLogging 
	implements WrapperPersistenceStoring
{
	private final PersistenceStoring wrapped;

	public PersistenceStoringWithLogging(final PersistenceStoring wrapped)
	{
		super();
		
		this.wrapped = wrapped;
	}
	
	@Override
	public PersistenceStoring wrapped()
	{
		return this.wrapped;
	}
	
	@Override
	public long store(Object instance)
	{
		Logger.getLogger(PersistenceStoring.class.getName())
			.info("Object stored: " + instance);
		
		return WrapperPersistenceStoring.super.store(instance);
	}
}
```