Class PingBean

  • All Implemented Interfaces:
    BaseClientInterface, PingClientInterface, PingOperationsInterface, java.lang.AutoCloseable

    public class PingBean
    extends java.lang.Object
    implements PingClientInterface, java.lang.AutoCloseable
    PingBean is a JavaBean that provides a mechanism for pinging any Apama TCP server that offers the Pingable interface (that should be all of them).

    Note that changes to the value of the "host", or "port" properties will cause the bean to attempt to re-connect to a Server running on a new host/port. This re-connection will happen immediately if the bean was connected at the time of the property change, but will happen later in a "lazy" fashion if there was no existing connection at the time of the property change.

    This bean also maintains Boolean bound property called "beanConnected", the value of which is maintained internally. The value will be set to true following a successful connection to a Server, and to false at the time of disconnection. Once connected, a background thread will periodically "ping" the remote Server. This background thread will also maintain the value of the "beanConnected" property each time it tests the connection.

    Warning: The bound properties supported by this bean will notify all registered listeners from within a synchronized block. Listeners should NOT invoke methods that would cause indirect calls back to synchronized methods in this bean. For example calls to System.exit(int) would cause a deadlock situation when the shutdown handler thread attempted to call disconnect(). However, direct calls from the listener onto synchronized methods of the bean (re-entry) is permitted.

    • Constructor Detail

      • PingBean

        public PingBean()
        Default constructor - as required to be a bean. Initialises the bean with default values for the properties. This default constructor does not make a connection to a remote server.
      • PingBean

        public PingBean​(java.lang.String socket_hostname,
                        int socket_port,
                        java.lang.String processName)
                 throws com.apama.util.CompoundException
        Full argument constructor. Calls the default constructor, then connects to a remote server.
        Parameters:
        socket_hostname - Name of the host where the remote server is running.
        socket_port - Port number on which the remote server is listening.
        Throws:
        com.apama.util.CompoundException - Thrown if any exceptions occur in the Client SDK.
    • Method Detail

      • connectNow

        public void connectNow()
                        throws com.apama.util.CompoundException
        Manually request that the bean connects to the remote server. Repeated calls are permitted, and attempting to connect a bean that is already connected is identical to calling pingServer() from the PingOperationsInterface.
        Specified by:
        connectNow in interface BaseClientInterface
        Throws:
        com.apama.util.CompoundException - Thrown if any exceptions occur in the Client SDK.
      • disconnect

        public void disconnect()
                        throws com.apama.util.CompoundException
        Disconnect from an server. Removes the reference to the PingableClient object.

        The beanConnected property is set to false, and the connection polling thread is terminated.

        It is intended that subclasses that override this method call super.disconnect() as the last statement after finishing their local disconnect functionality. Note however that it is _not_ necessary for all subclasses to override this method.

        Specified by:
        disconnect in interface BaseClientInterface
        Throws:
        com.apama.util.CompoundException - This implementation will never throw an exception, but subclasses will probably need to do so.
      • close

        public void close()
        Description copied from interface: BaseClientInterface
        Disconnects the client and also waits to ensure that all background threads and other resources associated with this object have been terminated or freed. This method should always be called before quitting the program. Never call this method while the target object is locked, or from a thread that is receiving events or handling a property change notification event from the target object.

        This method is invoked automatically on objects managed by the try-with-resources statement.

        Specified by:
        close in interface java.lang.AutoCloseable
        Specified by:
        close in interface BaseClientInterface
        See Also:
        AutoCloseable.close()
      • dispose

        @Deprecated
        public void dispose()
        Deprecated.
        Description copied from interface: BaseClientInterface
        Disconnects the client and also waits to ensure that all background threads and other resources associated with this object have been terminated or freed. This method should always be called before quitting the program. Never call this method while the target object is locked, or from a thread that is receiving events or handling a property change notification event from the target object.
        Specified by:
        dispose in interface BaseClientInterface
      • pingServer

        public void pingServer()
                        throws com.apama.util.CompoundException
        Manually test if the remote server process is alive and responding to client requests. This method makes a no-arg, void return, method call on the client interface of the server. If a connection is not yet established, this method will request a connection. In the event that a connection cannot be established, or an error during the ping, an CompoundException will be raised.
        Specified by:
        pingServer in interface PingOperationsInterface
        Throws:
        com.apama.util.CompoundException - when the ping fails.
      • getHost

        public java.lang.String getHost()
        Get the name of the host to be connected to. This is the name of the host on which the remote server to be monitored is running.
        Specified by:
        getHost in interface BaseClientInterface
        Returns:
        Name of the host where the remote server to be monitored is running.
      • setHost

        public void setHost​(java.lang.String newHostValue)
                     throws com.apama.util.CompoundException
        Setter for the host property. This is the name of the host on which the remote server to be monitored is running. Changing this property will cause any existing connection to be lost. If there was an existing connection, then a new connection will be created.
        Specified by:
        setHost in interface BaseClientInterface
        Parameters:
        newHostValue - The new value for the Host property.
        Throws:
        com.apama.util.CompoundException - Thrown if any exceptions occur in the Client SDK.
      • getPort

        public int getPort()
        Get the port number to be connected to. This is the port number on which the correlator to be remote server is listening.
        Specified by:
        getPort in interface BaseClientInterface
        Returns:
        Port number on which the correlator to be remote server is listening.
      • setPort

        public void setPort​(int newPortValue)
                     throws com.apama.util.CompoundException
        Setter for the port property. This is the port number on which the remote server to be monitored is listening. Changing this property will cause any existing connection to be lost. If there was an existing connection, then a new connection will be created.
        Specified by:
        setPort in interface BaseClientInterface
        Parameters:
        newPortValue - The new value for the Port property.
        Throws:
        com.apama.util.CompoundException - Thrown if any exceptions occur in the Client SDK.
      • getProcessName

        public java.lang.String getProcessName()
        Get the process Name in use This is the process name in use for this bean
        Specified by:
        getProcessName in interface BaseClientInterface
        Returns:
        Process name in use
      • setProcessName

        public void setProcessName​(java.lang.String newProcessName)
                            throws com.apama.util.CompoundException
        Setter for the process Name This is the process name property to use Changing this property will cause any existing connection to be lost. If there was an existing connection, then a new connection will be created.
        Specified by:
        setProcessName in interface BaseClientInterface
        Parameters:
        newProcessName - The new value for the process name property.
        Throws:
        com.apama.util.CompoundException - Thrown if any exceptions occur in the Client SDK.
      • isBeanConnected

        public boolean isBeanConnected()
        Another name for the getBeanConnected() method.
        Specified by:
        isBeanConnected in interface BaseClientInterface
        Returns:
        true if the bean has a connection to an server, false if not.
      • getBeanConnected

        public boolean getBeanConnected()
        Get the beanConnected property value. This is the status of the bean - connected, or not connected. It indicates if the PingBean has a valid instance of the Pingable interface.
        Specified by:
        getBeanConnected in interface BaseClientInterface
        Returns:
        true if the bean has a connection to a remote server, false if not.
      • isPolling

        public boolean isPolling()
        Determine if the connection is being tested in a background thread. Returns true if the background polling thread exists.
      • getConnectionPollingInterval

        public int getConnectionPollingInterval()
        Get the polling interval (in milliseconds) for the internal connection test thread.
        Specified by:
        getConnectionPollingInterval in interface BaseClientInterface
        Returns:
        the current interval in milliseconds
      • setConnectionPollingInterval

        public void setConnectionPollingInterval​(int milliseconds)
        Set the polling interval (in milliseconds) for the internal connection test thread. If the parameter is negative, then the default value will be used instead.
        Specified by:
        setConnectionPollingInterval in interface BaseClientInterface
        Parameters:
        milliseconds - the current interval in milliseconds
      • removePropertyChangeListener

        public void removePropertyChangeListener​(java.beans.PropertyChangeListener listener)
        Remove a property change listener.
        Specified by:
        removePropertyChangeListener in interface BaseClientInterface
        Parameters:
        listener - the listener to be removed.
      • addPropertyChangeListener

        public void addPropertyChangeListener​(java.beans.PropertyChangeListener listener)
        Add a property change listener. Use this method to be informed whenever the a property value is changed.
        Specified by:
        addPropertyChangeListener in interface BaseClientInterface
        Parameters:
        listener - the listener to be added.
      • removePropertyChangeListener

        public void removePropertyChangeListener​(java.lang.String propertyName,
                                                 java.beans.PropertyChangeListener listener)
        Remove a property change listener for a specific named property.
        Specified by:
        removePropertyChangeListener in interface BaseClientInterface
        Parameters:
        propertyName - the name of the property that was listened on.
        listener - the listener to be removed.
      • addPropertyChangeListener

        public void addPropertyChangeListener​(java.lang.String propertyName,
                                              java.beans.PropertyChangeListener listener)
        Add a property change listener for a specific named property.
        Specified by:
        addPropertyChangeListener in interface BaseClientInterface
        Parameters:
        propertyName - the name of the property to listen on.
        listener - the listener to be added.