Poll (Apache Tomcat 9.0.120 API Documentation)
Description: declaration: package: org.apache.tomcat.jni, class: Poll

# Class Poll

java.lang.Object
org.apache.tomcat.jni.Poll

@Deprecated public class Poll extends Object
Deprecated.
The scope of the APR/Native Library will be reduced in Tomcat 9.1.x / Tomcat Native 2.x and has been reduced in Tomcat 10.1.x / Tomcat Native 2.x onwards to only include those components required to provide OpenSSL integration with the NIO and NIO2 connectors.
Poll.

- ## Field Summary

  Fields
  Modifier and Type
  Field
  Description
  `static final int`
  `APR_NO_DESC`
  Deprecated.
  nothing here
  `static final int`
  `APR_POLL_FILE`
  Deprecated.
  descriptor refers to a file
  `static final int`
  `APR_POLL_LASTDESC`
  Deprecated.
  descriptor is the last one in the list
  `static final int`
  `APR_POLL_SOCKET`
  Deprecated.
  descriptor refers to a socket
  `static final int`
  `APR_POLLERR`
  Deprecated.
  Pending error
  `static final int`
  `APR_POLLHUP`
  Deprecated.
  Hangup occurred
  `static final int`
  `APR_POLLIN`
  Deprecated.
  Can read without blocking
  `static final int`
  `APR_POLLNVAL`
  Deprecated.
  Descriptor invalid
  `static final int`
  `APR_POLLOUT`
  Deprecated.
  Can write without blocking
  `static final int`
  `APR_POLLPRI`
  Deprecated.
  Priority data available
  `static final int`
  `APR_POLLSET_THREADSAFE`
  Deprecated.
  Adding or Removing a Descriptor is thread safe

- ## Constructor Summary

  Constructors
  Constructor
  Description
  `Poll()`
  Deprecated.

- ## Method Summary

  Modifier and Type
  Method
  Description
  `static int`
  `add(long pollset, long sock, int reqevents)`
  Deprecated.
  Add a socket to a pollset with the default timeout.
  `static int`
  `addWithTimeout(long pollset, long sock, int reqevents, long timeout)`
  Deprecated.
  Add a socket to a pollset with a specific timeout.
  `static long`
  `create(int size, long p, int flags, long ttl)`
  Deprecated.
  Setup a pollset object.
  `static int`
  `destroy(long pollset)`
  Deprecated.
  Destroy a pollset object
  `static long`
  `getTtl(long pollset)`
  Deprecated.
  Get the socket time to live.
  `static int`
  `interrupt(long pollset)`
  Deprecated.
  Make poll() return.
  `static int`
  `maintain(long pollset, long[] descriptors, boolean remove)`
  Deprecated.
  Maintain on the descriptor(s) in a pollset
  `static int`
  `poll(long pollset, long timeout, long[] descriptors, boolean remove)`
  Deprecated.
  Block for activity on the descriptor(s) in a pollset
  `static int`
  `pollset(long pollset, long[] descriptors)`
  Deprecated.
  Return all descriptor(s) in a pollset
  `static int`
  `remove(long pollset, long sock)`
  Deprecated.
  Remove a descriptor from a pollset
  `static void`
  `setTtl(long pollset, long ttl)`
  Deprecated.
  Set the socket time to live.
  `static boolean`
  `wakeable(long pollset)`
  Deprecated.
  Check if interrupt() is allowed.

  ### Methods inherited from class Object

  `clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

- ## Field Details

  - ### APR_POLLIN

    public static final int APR_POLLIN
    Deprecated.
    Can read without blocking
    See Also:
      - Constant Field Values

  - ### APR_POLLPRI

    public static final int APR_POLLPRI
    Deprecated.
    Priority data available
    See Also:
      - Constant Field Values

  - ### APR_POLLOUT

    public static final int APR_POLLOUT
    Deprecated.
    Can write without blocking
    See Also:
      - Constant Field Values

  - ### APR_POLLERR

    public static final int APR_POLLERR
    Deprecated.
    Pending error
    See Also:
      - Constant Field Values

  - ### APR_POLLHUP

    public static final int APR_POLLHUP
    Deprecated.
    Hangup occurred
    See Also:
      - Constant Field Values

  - ### APR_POLLNVAL

    public static final int APR_POLLNVAL
    Deprecated.
    Descriptor invalid
    See Also:
      - Constant Field Values

  - ### APR_POLLSET_THREADSAFE

    public static final int APR_POLLSET_THREADSAFE
    Deprecated.
    Adding or Removing a Descriptor is thread safe
    See Also:
      - Constant Field Values

  - ### APR_NO_DESC

    public static final int APR_NO_DESC
    Deprecated.
    nothing here
    See Also:
      - Constant Field Values

  - ### APR_POLL_SOCKET

    public static final int APR_POLL_SOCKET
    Deprecated.
    descriptor refers to a socket
    See Also:
      - Constant Field Values

  - ### APR_POLL_FILE

    public static final int APR_POLL_FILE
    Deprecated.
    descriptor refers to a file
    See Also:
      - Constant Field Values

  - ### APR_POLL_LASTDESC

    public static final int APR_POLL_LASTDESC
    Deprecated.
    descriptor is the last one in the list
    See Also:
      - Constant Field Values

- ## Constructor Details

  - ### Poll

    public Poll()
    Deprecated.

- ## Method Details

  - ### create

    public static long create(int size, long p, int flags, long ttl) throws Error
    Deprecated.
    Setup a pollset object. If flags equals APR_POLLSET_THREADSAFE, then a pollset is created on which it is safe to make concurrent calls to apr_pollset_add(), apr_pollset_remove() and apr_pollset_poll() from separate threads. This feature is only supported on some platforms; the apr_pollset_create() call will fail with APR_ENOTIMPL on platforms where it is not supported.
    Parameters:
      `size` - The maximum number of descriptors that this pollset can hold
      `p` - The pool from which to allocate the pollset
      `flags` - Optional flags to modify the operation of the pollset.
      `ttl` - Maximum time to live for a particular socket.
    Returns:
      The pointer in which to return the newly created object
    Throws:
      `Error` - Pollset creation failed

  - ### destroy

    public static int destroy(long pollset)
    Deprecated.
    Destroy a pollset object
    Parameters:
      `pollset` - The pollset to destroy
    Returns:
      the operation status

  - ### add

    public static int add(long pollset, long sock, int reqevents)
    Deprecated.
    Add a socket to a pollset with the default timeout.
    Parameters:
      `pollset` - The pollset to which to add the socket
      `sock` - The sockets to add
      `reqevents` - requested events
    Returns:
      the operation status

  - ### addWithTimeout

    public static int addWithTimeout(long pollset, long sock, int reqevents, long timeout)
    Deprecated.
    Add a socket to a pollset with a specific timeout.
    Parameters:
      `pollset` - The pollset to which to add the socket
      `sock` - The sockets to add
      `reqevents` - requested events
      `timeout` - requested timeout in microseconds (-1 for infinite)
    Returns:
      the operation status

  - ### remove

    public static int remove(long pollset, long sock)
    Deprecated.
    Remove a descriptor from a pollset
    Parameters:
      `pollset` - The pollset from which to remove the descriptor
      `sock` - The socket to remove
    Returns:
      the operation status

  - ### poll

    public static int poll(long pollset, long timeout, long[] descriptors, boolean remove)
    Deprecated.
    Block for activity on the descriptor(s) in a pollset
    Parameters:
      `pollset` - The pollset to use
      `timeout` - Timeout in microseconds
      `descriptors` - Array of signaled descriptors (output parameter) The descriptor array must be two times the size of pollset. and are populated as follows:

          descriptors[2n + 0] -> returned events
          descriptors[2n + 1] -> socket

      `remove` - Remove signaled descriptors from pollset
    Returns:
      Number of signaled descriptors (output parameter) or negative APR error code.

  - ### maintain

    public static int maintain(long pollset, long[] descriptors, boolean remove)
    Deprecated.
    Maintain on the descriptor(s) in a pollset
    Parameters:
      `pollset` - The pollset to use
      `descriptors` - Array of signaled descriptors (output parameter) The descriptor array must be the size of pollset. and are populated as follows:

          descriptors[n] -> socket

      `remove` - Remove signaled descriptors from pollset
    Returns:
      Number of signaled descriptors (output parameter) or negative APR error code.

  - ### setTtl

    public static void setTtl(long pollset, long ttl)
    Deprecated.
    Set the socket time to live.
    Parameters:
      `pollset` - The pollset to use
      `ttl` - Timeout in microseconds

  - ### getTtl

    public static long getTtl(long pollset)
    Deprecated.
    Get the socket time to live.
    Parameters:
      `pollset` - The pollset to use
    Returns:
      Timeout in microseconds

  - ### pollset

    public static int pollset(long pollset, long[] descriptors)
    Deprecated.
    Return all descriptor(s) in a pollset
    Parameters:
      `pollset` - The pollset to use
      `descriptors` - Array of descriptors (output parameter) The descriptor array must be two times the size of pollset. and are populated as follows:

          descriptors[2n + 0] -> returned events
          descriptors[2n + 1] -> socket

    Returns:
      Number of descriptors (output parameter) in the Poll or negative APR error code.

  - ### interrupt

    public static int interrupt(long pollset)
    Deprecated.
    Make poll() return.
    Parameters:
      `pollset` - The pollset to use
    Returns:
      Negative APR error code

  - ### wakeable

    public static boolean wakeable(long pollset)
    Deprecated.
    Check if interrupt() is allowed.
    Parameters:
      `pollset` - The pollset to use
    Returns:
      `true` if `interrupt(long)` is allowed, else `false`