Package org.apache.jmeter.visualizers.backend

# Class BackendListener

java.lang.Object
org.apache.jmeter.testelement.AbstractTestElement
org.apache.jmeter.visualizers.backend.BackendListener

All Implemented Interfaces:
  `Serializable`, `Cloneable`, `NoThreadClone`, `Searchable`, `Remoteable`, `SampleListener`, `org.apache.jmeter.testelement.TestElement`, `TestStateListener`, `Backend`

public class BackendListener extends AbstractTestElement implements Backend, Serializable, SampleListener, TestStateListener, NoThreadClone, Remoteable
Async Listener that delegates SampleResult handling to implementations of `BackendListenerClient`

Since:
  2.13
See Also:
  - Serialized Form

- ## Nested Class Summary

  ## Nested classes/interfaces inherited from interface org.apache.jmeter.testelement.TestElement

  `org.apache.jmeter.testelement.TestElement.Companion`

- ## Field Summary

  Fields
  Modifier and Type
  Field
  Description
  `static final String`
  `ARGUMENTS`
  Property key representing the arguments for the BackendListenerClient.
  `static final String`
  `CLASSNAME`
  Property key representing the classname of the BackendListenerClient to user.
  `static final String`
  `DEFAULT_QUEUE_SIZE`
  `static final String`
  `QUEUE_SIZE`
  Queue size

  ### Fields inherited from interface org.apache.jmeter.testelement.TestElement

  `COMMENTS, Companion, ENABLED, GUI_CLASS, NAME, TEST_CLASS`

- ## Constructor Summary

  Constructors
  Constructor
  Description
  `BackendListener()`
  Create a BackendListener.

- ## Method Summary

  Modifier and Type
  Method
  Description
  `Object`
  `clone()`
  `Arguments`
  `getArguments()`
  Get the arguments (parameters) for the BackendListenerClient to be executed with.
  `String`
  `getClassname()`
  Gets the Classname of the BackendListenerClient object
  `String`
  `getQueueSize()`
  Gets the queue size
  `void`
  `sampleOccurred(SampleEvent event)`
  A sample has started and stopped.
  `void`
  `sampleStarted(SampleEvent e)`
  A sample has started.
  `void`
  `sampleStopped(SampleEvent e)`
  A sample has stopped.
  `void`
  `setArguments(Arguments args)`
  Set the arguments (parameters) for the BackendListenerClient to be executed with.
  `void`
  `setClassname(String classname)`
  Sets the Classname of the BackendListenerClient object
  `void`
  `setQueueSize(String queueSize)`
  Sets the queue size
  `void`
  `testEnded()`
  Called once for all threads after the end of a test.
  `void`
  `testEnded(String host)`
  Method called at the end of the test.
  `void`
  `testStarted()`
  Called just before the start of the test from the main engine thread.
  `void`
  `testStarted(String host)`
  Called just before the start of the test from the main engine thread.

  ### Methods inherited from class org.apache.jmeter.testelement.AbstractTestElement

  `addPropertiesValues, addProperty, addProperty, addTestElement, canRemove, clear, clearTemporary, clearTestElementChildren, emptyTemporary, equals, getComment, getName, getProperty, getPropertyAsBoolean, getPropertyAsBoolean, getPropertyAsDouble, getPropertyAsFloat, getPropertyAsInt, getPropertyAsInt, getPropertyAsLong, getPropertyAsLong, getPropertyAsString, getPropertyAsString, getPropertyOrNull, getSearchableTokens, getThreadContext, getThreadName, hashCode, isEnabled, isRunningVersion, isTemporary, logProperties, mergeIn, propertyIterator, recoverRunningVersion, removeProperty, setComment, setEnabled, setName, setProperty, setProperty, setProperty, setProperty, setProperty, setProperty, setProperty, setProperty, setProperty, setRunningVersion, setTemporary, setThreadContext, setThreadName, traverse, traverseCollection, traverseMap, traverseProperty`

  ### Methods inherited from class java.lang.Object

  `finalize, getClass, notify, notifyAll, toString, wait, wait, wait`

  ### Methods inherited from interface org.apache.jmeter.testelement.TestElement

  `get, get, get, get, get, get, get, get, get, getOrCreate, getOrCreate, getOrNull, getOrNull, getOrNull, getPropertyOrNull, getProps, getSchema, getString, removed, removeProperty, set, set, set, set, set, set, set, set, set`

- ## Field Details

  - ### CLASSNAME

    public static final String CLASSNAME
    Property key representing the classname of the BackendListenerClient to user.
    See Also:
      - Constant Field Values

  - ### QUEUE_SIZE

    public static final String QUEUE_SIZE
    Queue size
    See Also:
      - Constant Field Values

  - ### ARGUMENTS

    public static final String ARGUMENTS
    Property key representing the arguments for the BackendListenerClient.
    See Also:
      - Constant Field Values

  - ### DEFAULT_QUEUE_SIZE

    public static final String DEFAULT_QUEUE_SIZE
    See Also:
      - Constant Field Values

- ## Constructor Details

  - ### BackendListener

    public BackendListener()
    Create a BackendListener.

- ## Method Details

  - ### clone

    public Object clone()
    Specified by:
      `clone` in interface `org.apache.jmeter.testelement.TestElement`
    Overrides:
      `clone` in class `AbstractTestElement`

  - ### sampleOccurred

    public void sampleOccurred(SampleEvent event)
    Description copied from interface: `SampleListener`
    A sample has started and stopped.
    Specified by:
      `sampleOccurred` in interface `SampleListener`
    Parameters:
      `event` - the `SampleEvent` that has occurred

  - ### testStarted

    public void testStarted()
    Description copied from interface: `TestStateListener`

    Called just before the start of the test from the main engine thread. This is before the test elements are cloned. Note that not all the test variables will have been set up at this point.

    N.B. testStarted() and testEnded() are called from different threads.

    Specified by:
      `testStarted` in interface `TestStateListener`
    See Also:
      - `StandardJMeterEngine.run()`

  - ### testStarted

    public void testStarted(String host)
    Description copied from interface: `TestStateListener`

    Called just before the start of the test from the main engine thread. This is before the test elements are cloned. Note that not all the test variables will have been set up at this point.

    N.B. testStarted() and testEnded() are called from different threads.

    Specified by:
      `testStarted` in interface `TestStateListener`
    Parameters:
      `host` - name of host
    See Also:
      - `StandardJMeterEngine.run()`

  - ### testEnded

    public void testEnded(String host)
    Method called at the end of the test. This is called only on one instance of BackendListener. This method will loop through all of the other BackendListenerClients which have been registered (automatically in the constructor) and notify them that the test has ended, allowing the BackendListenerClients to cleanup. Implements TestStateListener.testEnded(String)
    Specified by:
      `testEnded` in interface `TestStateListener`
    Parameters:
      `host` - name of host
    See Also:
      - `StandardJMeterEngine.stopTest()`

  - ### testEnded

    public void testEnded()
    Description copied from interface: `TestStateListener`

    Called once for all threads after the end of a test. This will use the same element instances as at the start of the test.

    N.B. testStarted() and testEnded() are called from different threads.

    Specified by:
      `testEnded` in interface `TestStateListener`
    See Also:
      - `StandardJMeterEngine.stopTest()`

  - ### sampleStarted

    public void sampleStarted(SampleEvent e)
    Description copied from interface: `SampleListener`
    A sample has started.
    Specified by:
      `sampleStarted` in interface `SampleListener`
    Parameters:
      `e` - the `SampleEvent` that has started

  - ### sampleStopped

    public void sampleStopped(SampleEvent e)
    Description copied from interface: `SampleListener`
    A sample has stopped.
    Specified by:
      `sampleStopped` in interface `SampleListener`
    Parameters:
      `e` - the `SampleEvent` that has stopped

  - ### setArguments

    public void setArguments(Arguments args)
    Set the arguments (parameters) for the BackendListenerClient to be executed with.
    Parameters:
      `args` - the new arguments. These replace any existing arguments.

  - ### getArguments

    public Arguments getArguments()
    Get the arguments (parameters) for the BackendListenerClient to be executed with.
    Returns:
      the arguments

  - ### setClassname

    public void setClassname(String classname)
    Sets the Classname of the BackendListenerClient object
    Parameters:
      `classname` - the new Classname value

  - ### getClassname

    public String getClassname()
    Gets the Classname of the BackendListenerClient object
    Returns:
      the Classname value

  - ### setQueueSize

    public void setQueueSize(String queueSize)
    Sets the queue size
    Parameters:
      `queueSize` - the size of the queue

  - ### getQueueSize

    public String getQueueSize()
    Gets the queue size
    Returns:
      int queueSize