Nashorn多线程编程

Question

如果以下代码在多线程应用程序中可以工作，您可以帮助我吗。

这是我的Java脚本，将由Nashorn评估

var Thread = Java.type("java.lang.Thread");
var referenceNumberValid = "0000";
var referenceNumberInvalid = "0001";

function validate (parameters) {
    var isValid = false;
    var statusCode;
    var referenceNumber = parameters.referenceNumber;
    var validateNumber = referenceNumber.substr(0, 7);
    var sum = 0;

    for (ctr = 0; ctr < validateNumber.length; ctr++) {
        sum += parseInt(validateNumber.substr(ctr, 1));
    }

    var checkDigit = sum % 10;
    isValid = parseInt(referenceNumber.substr(7, 1)) == checkDigit;
    statusCode = isValid ? referenceNumberValid : referenceNumberInvalid;

    print("Thread: " + Thread.currentThread().getId() + ", isValid: " + isValid + ", referenceNumber: " + referenceNumber + ", validateNumber: " + validateNumber + ", sum: " + sum + ", checkDigit: " + checkDigit + ", statusCode" + statusCode);

    return statusCode;
}

这就是我创建脚本引擎的方式

ScriptEngine engine = new ScriptEngineManager().getEngineByName("nashorn");
engine.eval(myScript);

在使用Testng进行测试时，此操作不会出现任何错误

@Test(dataProvider = "validReferenceNumbers", timeOut = 3000)
public final void testValidReferenceNumber(String referenceNumber) throws NoSuchMethodException, ScriptException {
    Map<String, String> parameters = new HashMap<>();
    parameters.put("referenceNumber", referenceNumber);   
    Invocable invocable = (Invocable) engine;
    Object result = invocable.invokeFunction("validate", parameters);       
    Assert.assertEquals(statusCode, "000");
}

@DataProvider(name = "validReferenceNumbers")
private Iterator<Object[]> validReferenceNumbers() throws FileNotFoundException {
    Iterator<Object[]> testData = null;  
    // please assume that will be initilized correctly 
    return testData;
}

测试结果1-请注意，有些数据是重复的

Thread: 10, isValid: true, referenceNumber: 18058888, validateNumber: 1805888, sum: 38, checkDigit: 8, statusCode0000
Thread: 11, isValid: true, referenceNumber: 18058888, validateNumber: 1805888, sum: 38, checkDigit: 8, statusCode0000
Thread: 12, isValid: true, referenceNumber: 17028884, validateNumber: 1702888, sum: 34, checkDigit: 4, statusCode0000
Thread: 13, isValid: true, referenceNumber: 18028885, validateNumber: 1802888, sum: 35, checkDigit: 5, statusCode0000
Thread: 14, isValid: true, referenceNumber: 18058888, validateNumber: 1805888, sum: 38, checkDigit: 8, statusCode0000
Thread: 15, isValid: true, referenceNumber: 17098881, validateNumber: 1709888, sum: 41, checkDigit: 1, statusCode0000
Thread: 16, isValid: true, referenceNumber: 17098881, validateNumber: 1709888, sum: 41, checkDigit: 1, statusCode0000
Thread: 17, isValid: true, referenceNumber: 18028885, validateNumber: 1802888, sum: 35, checkDigit: 5, statusCode0000
Thread: 18, isValid: true, referenceNumber: 18058888, validateNumber: 1805888, sum: 38, checkDigit: 8, statusCode0000
Thread: 19, isValid: true, referenceNumber: 17058887, validateNumber: 1705888, sum: 37, checkDigit: 7, statusCode0000
Thread: 20, isValid: true, referenceNumber: 18058888, validateNumber: 1805888, sum: 38, checkDigit: 8, statusCode0000
Thread: 21, isValid: true, referenceNumber: 18058888, validateNumber: 1805888, sum: 38, checkDigit: 8, statusCode0000
Thread: 22, isValid: true, referenceNumber: 18058888, validateNumber: 1805888, sum: 38, checkDigit: 8, statusCode0000
Thread: 23, isValid: true, referenceNumber: 18058888, validateNumber: 1805888, sum: 38, checkDigit: 8, statusCode0000
Thread: 24, isValid: true, referenceNumber: 18058888, validateNumber: 1805888, sum: 38, checkDigit: 8, statusCode0000
Thread: 25, isValid: true, referenceNumber: 18028885, validateNumber: 1802888, sum: 35, checkDigit: 5, statusCode0000
Thread: 26, isValid: true, referenceNumber: 18058888, validateNumber: 1805888, sum: 38, checkDigit: 8, statusCode0000
Thread: 27, isValid: true, referenceNumber: 18028885, validateNumber: 1802888, sum: 35, checkDigit: 5, statusCode0000
Thread: 28, isValid: true, referenceNumber: 18028885, validateNumber: 1802888, sum: 35, checkDigit: 5, statusCode0000
Thread: 29, isValid: true, referenceNumber: 18028885, validateNumber: 1802888, sum: 35, checkDigit: 5, statusCode0000
Thread: 30, isValid: true, referenceNumber: 18028885, validateNumber: 1802888, sum: 35, checkDigit: 5, statusCode0000
Thread: 31, isValid: true, referenceNumber: 18028885, validateNumber: 1802888, sum: 35, checkDigit: 5, statusCode0000
Thread: 32, isValid: true, referenceNumber: 18028885, validateNumber: 1802888, sum: 35, checkDigit: 5, statusCode0000
Thread: 33, isValid: true, referenceNumber: 17058887, validateNumber: 1705888, sum: 37, checkDigit: 7, statusCode0000
Thread: 34, isValid: true, referenceNumber: 18028885, validateNumber: 1802888, sum: 35, checkDigit: 5, statusCode0000
Thread: 35, isValid: true, referenceNumber: 18058888, validateNumber: 1805888, sum: 38, checkDigit: 8, statusCode0000
Thread: 36, isValid: true, referenceNumber: 18058888, validateNumber: 1805888, sum: 38, checkDigit: 8, statusCode0000
Thread: 37, isValid: true, referenceNumber: 18058888, validateNumber: 1805888, sum: 38, checkDigit: 8, statusCode0000
Thread: 38, isValid: true, referenceNumber: 18058888, validateNumber: 1805888, sum: 38, checkDigit: 8, statusCode0000
Thread: 39, isValid: true, referenceNumber: 18058888, validateNumber: 1805888, sum: 38, checkDigit: 8, statusCode0000
Thread: 40, isValid: true, referenceNumber: 18058888, validateNumber: 1805888, sum: 38, checkDigit: 8, statusCode0000
Thread: 41, isValid: true, referenceNumber: 18058888, validateNumber: 1805888, sum: 38, checkDigit: 8, statusCode0000
Thread: 42, isValid: true, referenceNumber: 18058888, validateNumber: 1805888, sum: 38, checkDigit: 8, statusCode0000
Thread: 43, isValid: true, referenceNumber: 18028885, validateNumber: 1802888, sum: 35, checkDigit: 5, statusCode0000
Thread: 44, isValid: true, referenceNumber: 18058888, validateNumber: 1805888, sum: 38, checkDigit: 8, statusCode0000
Thread: 45, isValid: true, referenceNumber: 18058888, validateNumber: 1805888, sum: 38, checkDigit: 8, statusCode0000
Thread: 46, isValid: true, referenceNumber: 07034880, validateNumber: 0703488, sum: 30, checkDigit: 0, statusCode0000
Thread: 47, isValid: true, referenceNumber: 07034880, validateNumber: 0703488, sum: 30, checkDigit: 0, statusCode0000
Thread: 48, isValid: true, referenceNumber: 07009882, validateNumber: 0700988, sum: 32, checkDigit: 2, statusCode0000

但是，如果我添加"并行=true"到@DataProvider我的脚本开始失败

@Test(dataProvider = "validReferenceNumbers", timeOut = 3000)
public final void testValidReferenceNumber(String referenceNumber) throws NoSuchMethodException, ScriptException {
    Map<String, String> parameters = new HashMap<>();
    parameters.put("referenceNumber", referenceNumber);   
    Invocable invocable = (Invocable) engine;
    Object result = invocable.invokeFunction("validate", parameters);       
    Assert.assertEquals(statusCode, "000");
}

@DataProvider(name = "validReferenceNumbers", parallel=true)
private Iterator<Object[]> validReferenceNumbers() throws FileNotFoundException {
    Iterator<Object[]> testData = null;  
    // please assume that will be initilized correctly 
    return testData;
}

测试结果2-请注意，重复一些数据，以表明相同的参考编号可能在测试过程中随机失败

Thread: 29, isValid: true, referenceNumber: 18058888, validateNumber: 1805888, sum: 38, checkDigit: 8, statusCode0000
Thread: 22, isValid: false, referenceNumber: 18058888, validateNumber: 1805888, sum: 1, checkDigit: 1, statusCode0001
Thread: 25, isValid: false, referenceNumber: 18058888, validateNumber: 1805888, sum: 1, checkDigit: 1, statusCode0001
Thread: 21, isValid: true, referenceNumber: 17098881, validateNumber: 1709888, sum: 41, checkDigit: 1, statusCode0000
Thread: 27, isValid: false, referenceNumber: 18028885, validateNumber: 1802888, sum: 1, checkDigit: 1, statusCode0001
Thread: 20, isValid: true, referenceNumber: 17098881, validateNumber: 1709888, sum: 41, checkDigit: 1, statusCode0000
Thread: 26, isValid: true, referenceNumber: 17058887, validateNumber: 1705888, sum: 37, checkDigit: 7, statusCode0000
Thread: 24, isValid: true, referenceNumber: 17028884, validateNumber: 1702888, sum: 34, checkDigit: 4, statusCode0000
Thread: 23, isValid: false, referenceNumber: 18028885, validateNumber: 1802888, sum: 1, checkDigit: 1, statusCode0001
Thread: 28, isValid: true, referenceNumber: 18058888, validateNumber: 1805888, sum: 38, checkDigit: 8, statusCode0000
Thread: 30, isValid: true, referenceNumber: 18058888, validateNumber: 1805888, sum: 38, checkDigit: 8, statusCode0000
Thread: 32, isValid: true, referenceNumber: 18028885, validateNumber: 1802888, sum: 35, checkDigit: 5, statusCode0000
Thread: 34, isValid: true, referenceNumber: 18028885, validateNumber: 1802888, sum: 35, checkDigit: 5, statusCode0000
Thread: 31, isValid: true, referenceNumber: 18058888, validateNumber: 1805888, sum: 38, checkDigit: 8, statusCode0000
Thread: 36, isValid: true, referenceNumber: 18028885, validateNumber: 1802888, sum: 35, checkDigit: 5, statusCode0000
Thread: 38, isValid: true, referenceNumber: 18058888, validateNumber: 1805888, sum: 38, checkDigit: 8, statusCode0000
Thread: 40, isValid: true, referenceNumber: 18028885, validateNumber: 1802888, sum: 35, checkDigit: 5, statusCode0000
Thread: 42, isValid: true, referenceNumber: 18028885, validateNumber: 1802888, sum: 35, checkDigit: 5, statusCode0000
Thread: 44, isValid: true, referenceNumber: 18058888, validateNumber: 1805888, sum: 38, checkDigit: 8, statusCode0000
Thread: 33, isValid: true, referenceNumber: 18028885, validateNumber: 1802888, sum: 35, checkDigit: 5, statusCode0000
Thread: 46, isValid: true, referenceNumber: 18058888, validateNumber: 1805888, sum: 38, checkDigit: 8, statusCode0000
Thread: 48, isValid: true, referenceNumber: 18058888, validateNumber: 1805888, sum: 38, checkDigit: 8, statusCode0000
Thread: 35, isValid: false, referenceNumber: 18058888, validateNumber: 1805888, sum: 30, checkDigit: 0, statusCode0001
Thread: 50, isValid: true, referenceNumber: 18058888, validateNumber: 1805888, sum: 38, checkDigit: 8, statusCode0000
Thread: 37, isValid: true, referenceNumber: 18058888, validateNumber: 1805888, sum: 38, checkDigit: 8, statusCode0000
Thread: 39, isValid: true, referenceNumber: 18028885, validateNumber: 1802888, sum: 35, checkDigit: 5, statusCode0000
Thread: 41, isValid: true, referenceNumber: 17058887, validateNumber: 1705888, sum: 37, checkDigit: 7, statusCode0000
Thread: 52, isValid: true, referenceNumber: 18058888, validateNumber: 1805888, sum: 38, checkDigit: 8, statusCode0000
Thread: 54, isValid: true, referenceNumber: 18058888, validateNumber: 1805888, sum: 38, checkDigit: 8, statusCode0000
Thread: 43, isValid: true, referenceNumber: 18028885, validateNumber: 1802888, sum: 35, checkDigit: 5, statusCode0000
Thread: 45, isValid: true, referenceNumber: 18058888, validateNumber: 1805888, sum: 38, checkDigit: 8, statusCode0000
Thread: 56, isValid: true, referenceNumber: 07009882, validateNumber: 0700988, sum: 32, checkDigit: 2, statusCode0000
Thread: 58, isValid: true, referenceNumber: 07034880, validateNumber: 0703488, sum: 30, checkDigit: 0, statusCode0000
Thread: 47, isValid: true, referenceNumber: 18058888, validateNumber: 1805888, sum: 38, checkDigit: 8, statusCode0000
Thread: 49, isValid: true, referenceNumber: 18058888, validateNumber: 1805888, sum: 38, checkDigit: 8, statusCode0000
Thread: 51, isValid: true, referenceNumber: 18058888, validateNumber: 1805888, sum: 38, checkDigit: 8, statusCode0000
Thread: 53, isValid: true, referenceNumber: 18028885, validateNumber: 1802888, sum: 35, checkDigit: 5, statusCode0000
Thread: 55, isValid: true, referenceNumber: 18058888, validateNumber: 1805888, sum: 38, checkDigit: 8, statusCode0000
Thread: 57, isValid: true, referenceNumber: 07034880, validateNumber: 0703488, sum: 30, checkDigit: 0, statusCode0000

有人可以确认我是否可以初始化ScriptEngine并允许它在多线程应用程序中使用吗。如您所见，我使用全局脚本变量，但这些变量在执行期间不会被修改。因为我们的设计围绕一个在内部调用此脚本的web服务。

P. S.在我的理解@DataProvider（并行=true）是测试多线程的正确方法，所以如果我错了，请指出它。

编辑有人能告诉我如何修改我的代码/脚本，以便我可以初始化ScriptEngine并允许它在多线程应用程序中使用。因为我不想一遍又一遍地解析脚本文件。

正如我之前所想的，如果脚本不使用全局变量来保持状态，它就可以了，但显然这还不够。

谢谢

Answer 1

您可以初始化脚本引擎，并在多线程应用程序中使用它。

而不是引擎。eval（myScript）您需要创建一个CompiledScript实例，稍后可以将其计算为Bindings实例：

Compilable compilable = (Compilable) engine;
CompiledScript script = compilable.compile(myScript);

您需要为每个线程/测试创建一个绑定实例，而不是将引擎用作一个可调用的实例，对编译后的脚本进行求值，获取封装函数的脚本对象镜像，然后调用函数：

@Test(dataProvider = "validReferenceNumbers", timeOut = 3000)
public final void testValidReferenceNumber(String referenceNumber) throws ScriptException {
    Map<String, String> parameters = new HashMap<>();
    parameters.put("referenceNumber", referenceNumber);
    Bindings bindings = engine.createBindings();
    script.eval(bindings);
    ScriptObjectMirror scriptObjectMirror = (ScriptObjectMirror) bindings.get("validate");
    Object result = scriptObjectMirror.call(null, parameters);
    /* insert result assertions here */
}

资料来源：

• https://stackoverflow.com/a/30159424/3255152
• 在Servlet中重用Nashorn ScriptEngine
• https://stackoverflow.com/a/32252478/3255152