RefCounted (Solr 9.0.0 core API)

java.lang.Object
- org.apache.solr.util.RefCounted<Type>

```
public abstract class RefCounted<Type>
extends Object
```
Keep track of a reference count on a resource and close it when the count hits zero.
By itself, this class could have some race conditions since there is no synchronization between the refcount check and the close. Solr's use in reference counting searchers is safe since the count can only hit zero if it's unregistered (and hence incref() will not be called again on it).

Field Summary

Fields
Modifier and Type Field Description

protected AtomicInteger refcount

protected Type resource

Constructor Summary

Constructors
Constructor Description

RefCounted(Type resource)

Method Summary

All Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method	Description
`protected abstract void`	`close()`
`void`	`decref()`
`Type`	`get()`
`int`	`getRefcount()`
`RefCounted<Type>`	`incref()`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

resource
```
protected final Type resource
```

refcount
```
protected final AtomicInteger refcount
```

Constructor Detail
- RefCounted
```
public RefCounted(Type resource)
```

Method Detail

getRefcount
```
public int getRefcount()
```

incref

public final RefCounted<Type> incref()

get
```
public final Type get()
```

decref
```
public void decref()
```

close
```
protected abstract void close()
```