---
name: "ACE_Unbounded_Queue"
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_Unbounded_Queue"
---

# ACE\_Unbounded\_Queue(3)

A Queue of "infinite" length.

## NAME

ACE\_Unbounded\_Queue -  A Queue of "infinite" length.

## SYNOPSIS

```
#include <ace/Containers.h>
template<class T>
class ACE_Unbounded_Queue
{
  public:
    friend class ACE_Unbounded_Queue_Iterator<T>;
    typedef ACE_Unbounded_Queue_Iterator<T> ITERATOR;
    ACE_Unbounded_Queue (ACE_Allocator *alloc = 0);
    ACE_Unbounded_Queue (const ACE_Unbounded_Queue<T> &);
    void operator= (const ACE_Unbounded_Queue<T> &);
    ~ACE_Unbounded_Queue (void);
    int is_empty (void) const;
    int is_full (void) const;
    int enqueue_tail (const T &new_item);
    int enqueue_head (const T &new_item);
    int dequeue_head (T &item);
    void reset (void);
    int get (T *&item, size_t slot = 0) const;
    int set (const T &item, size_t slot);
    size_t size (void) const;
    void dump (void) const;
    ACE_Unbounded_Queue_Iterator<T> begin (void);
    ACE_Unbounded_Queue_Iterator<T> end (void);
    ACE_ALLOC_HOOK_DECLARE;
  protected:
    void delete_nodes (void);
    void copy_nodes (const ACE_Unbounded_Queue<T> &);
    ACE_Node<T> *head_;
    size_t cur_size_;
    ACE_Allocator *allocator_;
};
```

## DESCRIPTION

This implementation of an unbounded queue uses a circular linked list with a dummy node.

## Initialization and termination methods.

```
ACE_Unbounded_Queue (ACE_Allocator *alloc = 0);
```

construction.  Use user specified allocation strategy if specified.

```
ACE_Unbounded_Queue (const ACE_Unbounded_Queue<T> &);
```

Copy constructor.

```
void operator= (const ACE_Unbounded_Queue<T> &);
```

Assignment operator.

```
~ACE_Unbounded_Queue (void);
```

construction.

## Check boundary conditions.

```
int is_empty (void) const;
```

Returns 1 if the container is empty, otherwise returns 0.

```
int is_full (void) const;
```

Returns 1 if the container is full, otherwise returns 0.

## Classic queue operations.

```
int enqueue_tail (const T &new_item);
```

Adds new\_item to the tail of the queue.  Returns 0 on success, -1 on failure.

```
int enqueue_head (const T &new_item);
```

Adds new\_item to the head of the queue.  Returns 0 on success, -1 on failure.

```
int dequeue_head (T &item);
```

Removes and returns the first item on the queue.  Returns 0 on success, -1 if the queue was empty.

## Additional utility methods.

```
void reset (void);
```

Reset the ACE\_Unbounded\_Queue to be empty and release all its dynamically allocated resources.

```
int get (T *&item, size_t slot = 0) const;
```

Get the slotth element in the set.  Returns -1 if the element isn't in the range {0..size - 1}, else 0.

```
int set (const T &item, size_t slot);
```

Set the slotth element in the set.  Will pad out the set with empty nodes if slot is beyond the range {0..size - 1}. Returns -1 on failure, 0 if slot isn't initially in range, and 0 otherwise.

```
size_t size (void) const;
```

The number of items in the queue.

```
void dump (void) const;
```

Dump the state of an object.

## STL-styled unidirectional iterator factory.

```
ACE_Unbounded_Queue_Iterator<T> begin (void);
```

```
ACE_Unbounded_Queue_Iterator<T> end (void);
```

```
ACE_ALLOC_HOOK_DECLARE;
```

Declare the dynamic allocation hooks.

## AUTHOR

Doug Schmidt

## Initialization and termination methods.

## Check boundary conditions.

## Classic unordered set operations.

## LIBRARY

ace