JMeter自定义函数

    在使用JMeter进行测试时，自带的函数可能不满足需求，这个时候需要自定义函数。
    先建立Maven工程，然后修改pom.xml，引入JMeter相关jar包。

    <dependencies>
        <dependency>
            <groupId>org.apache.jmeter</groupId>
            <artifactId>ApacheJMeter_functions</artifactId>
            <version>5.1.1</version>
        </dependency>
        <dependency>
            <groupId>org.apache.jmeter</groupId>
            <artifactId>ApacheJMeter_core</artifactId>
            <version>5.1.1</version>
        </dependency>
    </dependencies>

接下来即可实现自定义函数。该类所在包必须是org.apache.jmeter.functions，然后继承org.apache.jmeter.functions.Abstractfunction，实现4个方法。

package org.apache.jmeter.functions;

import java.util.Collection;
import java.util.linkedList;
import java.util.List;

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;

public class Testfunction extends Abstractfunction {
    private static final List<String> argumentDesc = new linkedList<String>();

    static {
        argumentDesc.add("原始内容");
    }

    // function名称
    private static final String KEY = "__Reverse";

    private static final int PARAM_COUNT_MAX = 1;
    private static final int PARAM_COUNT_MIN = 1;
    // 传入参数的值
    private Object[] values;

    public List<String> getArgumentDesc() {
        return argumentDesc;
    }

    @Override
    public String execute(SampleResult previousResult, Sampler currentSampler) throws InvalidvariableException {
        String original = ((Compoundvariable) values[0]).execute().trim();
        String result = reverse(original);
        return result;
    }

    private String reverse(final String original) {
        StringBuffer sbResult = new StringBuffer(original);
        return sbResult.reverse().toString();
    }

    @Override
    public String getReferenceKey() {
        return KEY;
    }

    @Override
    public void setParameters(Collection<Compoundvariable> parameters) throws InvalidvariableException {
        // 检查参数的个数是否正确
        checkParameterCount(parameters, PARAM_COUNT_MIN, PARAM_COUNT_MAX);
        // 将值存入类变量中
        values = parameters.toArray();
    }
}

编写完代码后，使用Maven生成jar包，拷贝至$JMETER_HOME/lib/ext目录下，重新启动JMeter