---
name: "ACE_Future_Observer"
section: "3"
platform: "linux"
package: "libace-doc"
version: "5.0.7-4"
release: "Debian 2.2 (Potato)"
platforms: ["linux"]
url: "https://new.carta.tech/ACE_Future_Observer"
---

# ACE\_Future\_Observer(3)

ACE\_Future\_ObserverT

## NAME

ACE\_Future\_Observer -  ACE\_Future\_ObserverT

## SYNOPSIS

```
#include <ace/Future.h>
template<class T>
class ACE_Future_Observer
{
  public:
    virtual ~ACE_Future_Observer (void);
    virtual void update (const ACE_Future<T> &future) = 0;
    ACE_ALLOC_HOOK_DECLARE;
  protected:
    ACE_Future_Observer (void);
};
```

## DESCRIPTION

An ACE\_Future\_Observer object implements an object that is subscribed with an ACE\_Future object so that it may be notified when the value of the ACE\_Future object is written to by a writer thread.

It uses the Observer pattern

## Destructor

```
virtual ~ACE_Future_Observer (void);
```

```
virtual void update (const ACE_Future<T> &future) = 0;
```

Called by the ACE\_Future in which we are subscribed to when its value is written to.

```
ACE_ALLOC_HOOK_DECLARE;
```

Declare the dynamic allocation hooks.

## Constructor

```
ACE_Future_Observer (void);
```

## AUTHOR (S)

Andres Kruse Andres.Kruse@cern.ch, Douglas C. Schmidt schmidt@cs.wustl.edu, Per Andersson Per.Andersson@hfera.ericsson.se, and John Tucker jtucker@infoglide.com

## LIBRARY

ace