jmeter添加自定义扩展函数之if判断

1，打开eclipse,新建maven工程，在pom中引用jmeter核心jar包，具体请看---https://www.cnblogs.com/guanyf/p/10863033.html---，这里就不再赘述

2，代码如下：

 package com.mytest.functions;

 import org.apache.jmeter.engine.util.CompoundVariable;

 import org.apache.jmeter.functions.AbstractFunction;

 import org.apache.jmeter.functions.InvalidVariableException;

 import org.apache.jmeter.samplers.SampleResult;

 import org.apache.jmeter.samplers.Sampler;

 import org.apache.jmeter.threads.JMeterVariables;

 import java.util.Collection;

 import java.util.LinkedList;

 import java.util.List;

 public class If extends AbstractFunction {

     private static final List<String> desc = new LinkedList<String>();

     private static final String KEY = "__if";

     static {

         desc.add("Actual value");

         desc.add("Expected value");

         desc.add("Result if actual == expected");

         desc.add("Result if actual != expected");

         desc.add("Name of variable in which to store the result (optional)");

     }

     private Object[] values;

     public If() {

     }

     @Override

     public synchronized String execute(SampleResult previousResult, Sampler currentSampler)

             throws InvalidVariableException {

         String actual = getParameter(0);

         String expected = getParameter(1);

         String result = null;

         if (actual.equals(expected)) {

             result = getParameter(2).toString();

         } else {

             result = getParameter(3).toString();

         }

         JMeterVariables vars = getVariables();

         if (vars != null && values.length > 4) {

             String varName = getParameter(4).trim();

             vars.put(varName, result);

         }

         return result;

     }

     @Override

     public synchronized void setParameters(Collection<CompoundVariable> parameters) throws InvalidVariableException {

         checkMinParameterCount(parameters, 4);

         values = parameters.toArray();

     }

     @Override

     public String getReferenceKey() {

         return KEY;

     }

     @Override

     public List<String> getArgumentDesc() {

         return desc;

     }

     private String getParameter(int i) {

         return ((CompoundVariable) values[i]).execute();

     }

 }