/*
* Sun Public License
*
* The contents of this file are subject to the Sun Public License Version
* 1.0 (the "License"). You may not use this file except in compliance with
* the License. A copy of the License is available at http://www.sun.com/
*
* The Original Code is the SLAMD Distributed Load Generation Engine.
* The Initial Developer of the Original Code is Neil A. Wilson.
* Portions created by Neil A. Wilson are Copyright (C) 2004-2010.
* Some preexisting portions Copyright (C) 2002-2006 Sun Microsystems, Inc.
* All Rights Reserved.
*
* Contributor(s): Neil A. Wilson
*/
package com.slamd.scripting.general;
import java.util.Random;
import com.unboundid.util.ValuePattern;
import com.slamd.scripting.engine.Argument;
import com.slamd.scripting.engine.Method;
import com.slamd.scripting.engine.ScriptException;
import com.slamd.scripting.engine.Variable;
/**
* This class defines a variable that can be used to generate values based on a
* user-defined pattern. That pattern may include a numeric range that
* indicates that values should be chosen at random or in sequential order.
*
* <UL>
* <LI>assign(string valueString) -- Specifies the value string that should
* be parsed to create the returned value.</LI>
* <LI>nextValue() -- Retrieves the next value that was generated from the
* pattern as a string value.</LI>
* </UL>
*
*
* @author Neil A. Wilson
*/
public class ValuePatternVariable
extends Variable
{
/**
* The name that will be used for the data type of value pattern variables.
*/
public static final String VALUE_PATTERN_VARIABLE_TYPE = "valuepattern";
/**
* The name of the method that will be used to specify the pattern to use to
* construct the values.
*/
public static final String ASSIGN_METHOD_NAME = "assign";
/**
* The method number for the first "assign" method.
*/
public static final int ASSIGN_1_METHOD_NUMBER = 0;
/**
* The method number for the second "assign" method.
*/
public static final int ASSIGN_2_METHOD_NUMBER = 1;
/**
* The name of the method that will retrieve the next value based on the
* user-defined pattern.
*/
public static final String NEXT_VALUE_METHOD_NAME = "nextvalue";
/**
* The method number for the "nextValue" method.
*/
public static final int NEXT_VALUE_METHOD_NUMBER = 2;
// The parent random number generator to use to initialize the generators for
// each thread.
static Random parentRandom = new Random();
/**
* The set of methods associated with file URL variables.
*/
public static final Method[] VALUE_PATTERN_VARIABLE_METHODS = new Method[]
{
new Method(ASSIGN_METHOD_NAME,
new String[] { StringVariable.STRING_VARIABLE_TYPE }, null),
new Method(ASSIGN_METHOD_NAME,
new String[] { StringVariable.STRING_VARIABLE_TYPE,
StringVariable.STRING_VARIABLE_TYPE }, null),
new Method(NEXT_VALUE_METHOD_NAME, new String[0],
StringVariable.STRING_VARIABLE_TYPE),
};
// The value pattern to use to construct the values.
ValuePattern pattern;
/**
* Creates a new variable with no name, to be used only when creating a
* variable with <CODE>Class.newInstance()</CODE>, and only when
* <CODE>setName()</CODE> is called after that to set the name.
*
* @throws ScriptException If a problem occurs while initializing the new
* variable.
*/
public ValuePatternVariable()
throws ScriptException
{
try
{
pattern = new ValuePattern("");
} catch (Exception e) {}
}
/**
* Retrieves the URL string for this file URL variable.
*
* @return The URL string for this file URL variable.
*/
public String nextValue()
{
return pattern.nextValue();
}
/**
* Retrieves the name of the variable type for this variable.
*
* @return The name of the variable type for this variable.
*/
@Override()
public String getVariableTypeName()
{
return VALUE_PATTERN_VARIABLE_TYPE;
}
/**
* Retrieves a list of all methods defined for this variable.
*
* @return A list of all methods defined for this variable.
*/
@Override()
public Method[] getMethods()
{
return VALUE_PATTERN_VARIABLE_METHODS;
}
/**
* Indicates whether this variable type has a method with the specified name.
*
* @param methodName The name of the method.
*
* @return <CODE>true</CODE> if this variable has a method with the specified
* name, or <CODE>false</CODE> if it does not.
*/
@Override()
public boolean hasMethod(String methodName)
{
for (int i=0; i < VALUE_PATTERN_VARIABLE_METHODS.length; i++)
{
if (VALUE_PATTERN_VARIABLE_METHODS[i].getName().equals(methodName))
{
return true;
}
}
return false;
}
/**
* Retrieves the method number for the method that has the specified name and
* argument types, or -1 if there is no such method.
*
* @param methodName The name of the method.
* @param argumentTypes The list of argument types for the method.
*
* @return The method number for the method that has the specified name and
* argument types.
*/
@Override()
public int getMethodNumber(String methodName, String[] argumentTypes)
{
for (int i=0; i < VALUE_PATTERN_VARIABLE_METHODS.length; i++)
{
if (VALUE_PATTERN_VARIABLE_METHODS[i].hasSignature(methodName,
argumentTypes))
{
return i;
}
}
return -1;
}
/**
* Retrieves the return type for the method with the specified name and
* argument types.
*
* @param methodName The name of the method.
* @param argumentTypes The set of argument types for the method.
*
* @return The return type for the method, or <CODE>null</CODE> if there is
* no such method defined.
*/
@Override()
public String getReturnTypeForMethod(String methodName,
String[] argumentTypes)
{
for (int i=0; i < VALUE_PATTERN_VARIABLE_METHODS.length; i++)
{
if (VALUE_PATTERN_VARIABLE_METHODS[i].hasSignature(methodName,
argumentTypes))
{
return VALUE_PATTERN_VARIABLE_METHODS[i].getReturnType();
}
}
return null;
}
/**
* Executes the specified method, using the provided variables as arguments
* to the method, and makes the return value available to the caller.
*
* @param lineNumber The line number of the script in which the method
* call occurs.
* @param methodNumber The method number of the method to execute.
* @param arguments The set of arguments to use for the method.
*
* @return The value returned from the method, or <CODE>null</CODE> if it
* does not return a value.
*
* @throws ScriptException If the specified method does not exist, or if a
* problem occurs while attempting to execute it.
*/
@Override()
public Variable executeMethod(int lineNumber, int methodNumber,
Argument[] arguments)
throws ScriptException
{
switch (methodNumber)
{
case ASSIGN_1_METHOD_NUMBER:
// Read the value pattern to use and don't return a value.
StringVariable sv = (StringVariable) arguments[0].getArgumentValue();
try
{
pattern = new ValuePattern(sv.getStringValue());
}
catch (Exception e)
{
throw new ScriptException(lineNumber,
"Unable to parse the provided value pattern: " + e, e);
}
return null;
case ASSIGN_2_METHOD_NUMBER:
// Read the value pattern and format string to use and don't return a
// value.
StringVariable sv1 = (StringVariable) arguments[0].getArgumentValue();
StringVariable sv2 = (StringVariable) arguments[1].getArgumentValue();
String fmt = sv1.getStringValue() + '%' + sv2.getStringValue();
try
{
pattern = new ValuePattern(fmt);
}
catch (Exception e)
{
throw new ScriptException(lineNumber,
"Unable to parse the provided value pattern: " + e, e);
}
return null;
case NEXT_VALUE_METHOD_NUMBER:
// Return the set of lines read as a string array.
return new StringVariable(nextValue());
default:
throw new ScriptException(lineNumber,
"There is no method " + methodNumber +
" defined for " + getArgumentType() +
" variables.");
}
}
/**
* Assigns the value of the provided argument to this variable. The value of
* the provided argument must be of the same type as this variable.
*
* @param argument The argument whose value should be assigned to this
* variable.
*
* @throws ScriptException If a problem occurs while performing the
* assignment.
*/
@Override()
public void assign(Argument argument)
throws ScriptException
{
if (! argument.getArgumentType().equals(VALUE_PATTERN_VARIABLE_TYPE))
{
throw new ScriptException("Attempt to assign an argument of type " +
argument.getArgumentType() +
" to a variable of type " +
VALUE_PATTERN_VARIABLE_TYPE + " rejected.");
}
ValuePatternVariable vpv =
(ValuePatternVariable) argument.getArgumentValue();
pattern = vpv.pattern;
}
/**
* Retrieves a string representation of the value of this argument.
*
* @return A string representation of the value of this argument.
*/
public String getValueAsString()
{
return pattern.toString();
}
}