Package org.apache.jmeter.functions

Class StringFromFile

java.lang.Object
org.apache.jmeter.functions.AbstractFunction
org.apache.jmeter.functions.StringFromFile
All Implemented Interfaces:
Function, TestStateListener
@AutoService(Function.class) public class StringFromFile extends AbstractFunction implements TestStateListener

StringFromFile Function to read a String from a text file.

Parameters:
  • file name
  • variable name (optional - defaults to StringFromFile_)
  • sequence start
  • sequence end
Returns:
  • the next line from the file
  • or **ERR** if an error occurs
  • value is also saved in the variable for later re-use.

Ensure that different variable names are used for each call to the function

Notes:
  • JMeter instantiates a single copy of each function for every reference in the test plan
  • Function instances are shared between threads.
  • Each StringFromFile instance reads the file independently. The output variable can be used to save the value for later use in the same thread.
  • The file name is resolved at file (re-)open time; the file is initially opened on first execution (which could be any thread)
  • the output variable name is resolved every time the function is invoked
Because function instances are shared, it does not make sense to use the thread number as part of the file name.
Since:
1.9

  • Constructor Details

    • StringFromFile

      public StringFromFile()

  • Method Details

    • execute

      public String execute(SampleResult previousResult, Sampler currentSampler) throws InvalidVariableException

      N.B. execute() should be synchronized if function is operating with non-thread-safe objects (e.g. operates with files).

      JMeter ensures setParameters() happens-before execute(): setParameters is executed in main thread, and worker threads are started after that.
      Specified by:
      execute in interface Function
      Specified by:
      execute in class AbstractFunction
      Parameters:
      previousResult - The previous SampleResult
      currentSampler - The current Sampler
      Returns:
      The replacement value, which was generated by the function
      Throws:
      InvalidVariableException - - when the variables for the function call can't be evaluated
      See Also:

    • setParameters

      public void setParameters(Collection<CompoundVariable> parameters) throws InvalidVariableException
      Note: This is always called even if no parameters are provided (versions of JMeter after 2.3.1)
      Specified by:
      setParameters in interface Function
      Specified by:
      setParameters in class AbstractFunction
      Parameters:
      parameters - The parameters for the function call
      Throws:
      InvalidVariableException - - when the variables for the function call can't be evaluated
      See Also:

    • getReferenceKey

      public String getReferenceKey()
      Return the name of your function. Convention is to prepend "__" to the name (ie "__regexFunction")
      Specified by:
      getReferenceKey in interface Function
      Specified by:
      getReferenceKey in class AbstractFunction
      Returns:
      The name of the function
      See Also:

    • getArgumentDesc

      public List<String> getArgumentDesc()
      Return a list of strings briefly describing each parameter your function takes. Please use JMeterUtils.getResString(resource_name) to grab a resource string. Otherwise, your help text will be difficult to internationalize. This list is not optional. If you don't wish to write help, you must at least return a List containing the correct number of blank strings, one for each argument.
      Specified by:
      getArgumentDesc in interface Function
      Returns:
      List with brief descriptions for each parameter the function takes

    • testStarted

      public void testStarted()

      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:

    • testStarted

      public void testStarted(String host)

      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:

    • testEnded

      public void testEnded()

      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:

    • testEnded

      public void testEnded(String host)

      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
      Parameters:
      host - name of host
      See Also: