Package org.apache.derby.impl.drda

Class NetworkServerMBeanImpl

  • All Implemented Interfaces:
    NetworkServerMBean
    class NetworkServerMBeanImpl
extends java.lang.Object
implements NetworkServerMBean

    This is an implementation of the org.apache.derby.mbeans.drda.NetworkServerMBean, providing management and monitoring capabilities related to the Network Server through JMX.

    This bean uses callbacks to the NetworkServerControlImpl class instead of invoking NetworkServerControl, as it is the impl class that contains most of the information we want to expose via JMX.

    See Also:
    NetworkServerMBean

    • Field Detail

      • startTime

        private final long startTime

      • lastReceiveTime

        private long lastReceiveTime

      • lastReceiveBytes

        private long lastReceiveBytes

      • receiveResult

        private int receiveResult

      • lastSentTime

        private long lastSentTime

      • lastSentBytes

        private long lastSentBytes

      • sentResult

        private int sentResult

    • Method Detail

      • checkControl

        private static void checkControl()
        Ensure the caller has permission to control the network server.

      • checkMonitor

        private static void checkMonitor()
        Ensure the caller has permission to monitor the network server.

      • checkPermission

        private static void checkPermission​(SystemPermission permission)

      • getDrdaHost

        public java.lang.String getDrdaHost()
        Description copied from interface: NetworkServerMBean

        Gets the network interface address on which the Network Server is listening. This corresponds to the value of the derby.drda.host property.

        For example, the value "localhost" means that the Network Server is listening on the local loopback interface only.

        The special value "0.0.0.0" (IPv4 environments only) represents the "unspecified address" - also known as the anylocal or wildcard address. In this context this means that the server is listening on all network interfaces (and may thus be able to see connections from both the local host as well as remote hosts, depending on which network interfaces are available).

        Requires SystemPermission("server", "control") if a security manager is installed.

        Specified by:
        getDrdaHost in interface NetworkServerMBean
        Returns:
        the the network interface address on which the Network Server is listening (derby.drda.host)

      • getDrdaKeepAlive

        public boolean getDrdaKeepAlive()
        Description copied from interface: NetworkServerMBean

        Reports whether or not the Derby Network Server will send keep-alive probes and attempt to clean up connections for disconnected clients (the value of the derby.drda.keepAlive property).

        If true, a keep-alive probe is sent to the client if a "long time" (by default, more than two hours) passes with no other data being sent or received. This will detect and clean up connections for clients on powered-off machines or clients that have disconnected unexpectedly.

        If false, Derby will not attempt to clean up connections from disconnected clients, and will not send keep-alive probes.

        Requires SystemPermission("server", "monitor") if a security manager is installed.

        See also the documentation for the property derby.drda.keepAlive in the Derby Server and Administration Guide, section Managing the Derby Network Server, subsection Setting Network Server Properties, subsubsection derby.drda.keepAlive property.

        Specified by:
        getDrdaKeepAlive in interface NetworkServerMBean
        Returns:
        true if Derby Network Server will send keep-alive probes and attempt to clean up connections for disconnected clients (derby.drda.keepAlive)

      • getDrdaMaxThreads

        public int getDrdaMaxThreads()
        Description copied from interface: NetworkServerMBean

        Reports the maximum number of client connection threads the Network Server will allocate at any given time. This corresponds to the derby.drda.maxThreads property.

        Requires SystemPermission("server", "monitor") if a security manager is installed.

        Specified by:
        getDrdaMaxThreads in interface NetworkServerMBean
        Returns:
        the maximum number of client connection threads the Network Server will allocate at any given time (derby.drda.maxThreads)

      • getDrdaPortNumber

        public int getDrdaPortNumber()
        Description copied from interface: NetworkServerMBean

        Gets the port number on which the Network Server is listening for client connections. This corresponds to the value of the derby.drda.portNumber Network Server setting.

        Requires SystemPermission("server", "control") if a security manager is installed.

        Specified by:
        getDrdaPortNumber in interface NetworkServerMBean
        Returns:
        the port number on which the Network Server is listening for client connections.

      • getDrdaSecurityMechanism

        public java.lang.String getDrdaSecurityMechanism()
        Description copied from interface: NetworkServerMBean

        The Derby security mechanism required by the Network Server for all client connections. This corresponds to the value of the derby.drda.securityMechanism property on the server.

        If not set, the empty String will be returned, which means that the Network Server accepts any connection which uses a valid security mechanism.

        For a list of valid security mechanisms, refer to the documentation for the derby.drda.securityMechanism property in the Derby Server and Administration Guide.

        Requires SystemPermission("server", "control") if a security manager is installed.

        Specified by:
        getDrdaSecurityMechanism in interface NetworkServerMBean
        Returns:
        the security mechanism required by the Network Server for all client connections (derby.drda.securityMechanism)

      • getDrdaSslMode

        public java.lang.String getDrdaSslMode()
        Description copied from interface: NetworkServerMBean

        Reports whether client connections must be encrypted using Secure Sockets Layer (SSL), and whether certificate based peer authentication is enabled. Refers to the derby.drda.sslMode property.

        Peer authentication means that the other side of the SSL connection is authenticated based on a trusted certificate installed locally.

        The value returned is one of "off" (no SSL encryption), "basic" (SSL encryption, no peer authentication) and "peerAuthentication" (SSL encryption and peer authentication). Refer to the Derby Server and Administration Guide for more details.

        Requires SystemPermission("server", "control") if a security manager is installed.

        Specified by:
        getDrdaSslMode in interface NetworkServerMBean
        Returns:
        whether client connections must be encrypted using Secure Sockets Layer (SSL), and whether certificate based peer authentication is enabled (derby.drda.sslMode)

      • getDrdaStreamOutBufferSize

        public int getDrdaStreamOutBufferSize()
        Description copied from interface: NetworkServerMBean

        The size of the buffer used for streaming BLOB and CLOB from server to client. Refers to the derby.drda.streamOutBufferSize property.

        This setting may improve streaming performance when the default sizes of packets being sent are significantly smaller than the maximum allowed packet size in the network.

        Requires SystemPermission("server", "monitor") if a security manager is installed.

        Specified by:
        getDrdaStreamOutBufferSize in interface NetworkServerMBean
        Returns:
        the size of the buffer used for streaming blob/clob from server to client (derby.drda.streamOutBufferSize)

      • getDrdaTimeSlice

        public int getDrdaTimeSlice()
        Description copied from interface: NetworkServerMBean

        If the server property derby.drda.maxThreads is set to a non-zero value, this is the number of milliseconds that each client connection will actively use in the Network Server before yielding to another connection. If this value is 0, a waiting connection will become active once a currently active connection is closed.

        Refers to the derby.drda.timeSlice server property.

        Requires SystemPermission("server", "monitor") if a security manager is installed.

        Specified by:
        getDrdaTimeSlice in interface NetworkServerMBean
        Returns:
        the number of milliseconds that each client connection will actively use in the Network Server before yielding to another connection (derby.drda.timeSlice)
        See Also:
        NetworkServerMBean.getDrdaMaxThreads()

      • getDrdaTraceAll

        public boolean getDrdaTraceAll()
        Description copied from interface: NetworkServerMBean

        Whether server-side tracing is enabled for all client connections (sessions). Refers to the derby.drda.traceAll server property.

        Tracing may for example be useful when providing technical support information. The Network Server also supports tracing for individual connections (sessions), see the Derby Server and Administration Guide ("Controlling tracing by using the trace facility") for details.

        When tracing is enabled, tracing information from each client connection will be written to a separate trace file.

        Requires SystemPermission("server", "monitor") if a security manager is installed.

        Specified by:
        getDrdaTraceAll in interface NetworkServerMBean
        Returns:
        whether tracing for all client connections is enabled (derby.drda.traceAll)
        See Also:
        NetworkServerMBean.getDrdaTraceDirectory()

      • getDrdaTraceDirectory

        public java.lang.String getDrdaTraceDirectory()
        Description copied from interface: NetworkServerMBean

        Indicates the location of tracing files on the server host, if server tracing has been enabled.

        If the server setting derby.drda.traceDirectory is set, its value will be returned. Otherwise, the Network Server's default values will be taken into account when producing the result.

        Requires SystemPermission("server", "control") if a security manager is installed.

        Specified by:
        getDrdaTraceDirectory in interface NetworkServerMBean
        Returns:
        the potential location of tracing files on the server host
        See Also:
        NetworkServerMBean.getDrdaTraceAll()

      • getActiveConnectionCount

        public int getActiveConnectionCount()
        Description copied from interface: NetworkServerMBean

        Gets the number of currently active connections. All connections are active if the DrdaMaxThreads attribute (derby.drda.maxThreads property) is 0.

        If DrdaMaxThreads is > 0 and DrdaTimeSlice is 0, connections remain active until they are closed. If there are more than DrdaMaxThreads connections, inactive connections will be waiting for some active connection to close. The connection request will return when the connection becomes active.

        If DrdaMaxThreads is > 0 and DrdaTimeSlice > 0, connections will be alternating beetween active and waiting according to Derby's time slicing algorithm.

        Requires SystemPermission("server", "monitor") if a security manager is installed.

        Specified by:
        getActiveConnectionCount in interface NetworkServerMBean
        Returns:
        the number of active connections
        See Also:
        NetworkServerMBean.getDrdaMaxThreads(), NetworkServerMBean.getDrdaTimeSlice(), NetworkServerMBean.getWaitingConnectionCount()

      • getConnectionThreadPoolSize

        public int getConnectionThreadPoolSize()
        Description copied from interface: NetworkServerMBean

        Get the size of the connection thread pool. If DrdaMaxThreads (derby.drda.maxThreads) is set to a non-zero value, the size of the thread pool will not exceed this value.

        Requires SystemPermission("server", "monitor") if a security manager is installed.

        Specified by:
        getConnectionThreadPoolSize in interface NetworkServerMBean
        Returns:
        the size of the Network Server's connection thread pool
        See Also:
        NetworkServerMBean.getDrdaMaxThreads()

      • getAccumulatedConnectionCount

        public int getAccumulatedConnectionCount()
        Description copied from interface: NetworkServerMBean

        Gets the accumulated number of connections. This includes all active and waiting connections since the Network Server was started. This number will not decrease as long as the Network Server is running.

        Require SystemPermission("server", "monitor") if a security manager is installed.

        Specified by:
        getAccumulatedConnectionCount in interface NetworkServerMBean
        Returns:
        the accumulated number of connections made since server startup

      • getBytesReceived

        public long getBytesReceived()
        Description copied from interface: NetworkServerMBean

        Gets the total number of bytes read by the server since it was started.

        Require SystemPermission("server", "monitor") if a security manager is installed.

        Specified by:
        getBytesReceived in interface NetworkServerMBean
        Returns:
        the total number of bytes received by the server

      • getBytesSent

        public long getBytesSent()
        Description copied from interface: NetworkServerMBean

        Gets the total number of bytes written by the server since it was started.

        Requires SystemPermission("server", "monitor") if a security manager is installed.

        Specified by:
        getBytesSent in interface NetworkServerMBean
        Returns:
        the total number of bytes sent by the server

      • getBytesReceivedPerSecond

        public int getBytesReceivedPerSecond()
        Description copied from interface: NetworkServerMBean

        Gets the number of bytes received per second by the Network Server. This number is calculated by taking into account the number of bytes received since the last calculation (or since MBean startup if it is the first time this attibute is being read).

        The shortest interval measured is 1 second. This means that a new value will not be calculated unless there has been at least 1 second since the last calculation.

        Requires SystemPermission("server", "monitor") if a security manager is installed.

        Specified by:
        getBytesReceivedPerSecond in interface NetworkServerMBean
        Returns:
        the number of bytes received per second

      • getBytesSentPerSecond

        public int getBytesSentPerSecond()
        Description copied from interface: NetworkServerMBean

        Gets the number of bytes sent per second by the Network Server. This number is calculated by taking into account the number of bytes sent since the last calculation (or since MBean startup if it is the first time this attibute is being read).

        The shortest interval measured is 1 second. This means that a new value will not be calculated unless there has been at least 1 second since the last calculation.

        Requires SystemPermission("server", "monitor") if a security manager is installed.

        Specified by:
        getBytesSentPerSecond in interface NetworkServerMBean
        Returns:
        the number of bytes sent per millisecond

      • getStartTime

        public long getStartTime()
        Return start time.
        Specified by:
        getStartTime in interface NetworkServerMBean
        Returns:
        the difference, measured in milliseconds, between the time the Network Server was started and Unix epoch (1970-01-01T00:00:00Z)
        See Also:
        System.currentTimeMillis()

      • getServerProperty

        private java.lang.String getServerProperty​(java.lang.String property)
        Gets the value of a specific network server setting (property). Most server-related property keys have the prefix derby.drda. and may be found in the org.apache.derby.iapi.reference.Property class.
        Parameters:
        property - the name of the server property
        Returns:
        the value of the given server property
        See Also:
        Property