RestFuse的研究(三) Junit的Rule的使用和分析
????????? 在junit中定义一些可以公用的规则(Rule),类似拦截器和拦截器链的概念.在Junit4版本中针对不同的版本Rule的接口不一样,在Junit4.11和Junit4.10 采用实现TestRule接口.在Junit4.8采用的MethodRule接口.
备注:
???????? RestFuse使用1.2.0,
????????? Junit采用4.10版本.
如在RestFuse中定义Destination实现TestRule接口.实现apply方法:
public Statement apply(Statement base, Description description);
?
使用如下:
package com.easyway.restfuse;import org.junit.Rule;import org.junit.runner.RunWith;import com.eclipsesource.restfuse.Destination;import com.eclipsesource.restfuse.HttpJUnitRunner;import com.eclipsesource.restfuse.Method;import com.eclipsesource.restfuse.Response;import com.eclipsesource.restfuse.annotation.Context;import com.eclipsesource.restfuse.annotation.HttpTest;/** * * @author longgangbai * */@RunWith( HttpJUnitRunner.class )public class RestfuseTest { @Rule public Destination destination = new Destination("", "http://restfuse.com" ); @Context private Response response; // will be injected after every request @HttpTest( method = Method.GET, path = "/" ) public void checkRestfuseOnlineStatus() { System.out.println( response); } }?
在junit4中Rule怎么调用的呢?
???? 在BlockJUnit4ClassRunner中的methodBlock中进行测试方法的各种操作.如BeforeMethod,AfterMethod等的组装为Statement .
protected Statement methodBlock(FrameworkMethod method) {Object test;try {test = new ReflectiveCallable() {protected Object runReflectiveCall() throws Throwable {return BlockJUnit4ClassRunner.this.createTest();}}.run();} catch (Throwable e) {return new Fail(e);}Statement statement = methodInvoker(method, test);statement = possiblyExpectingExceptions(method, test, statement);statement = withPotentialTimeout(method, test, statement);statement = withBefores(method, test, statement);statement = withAfters(method, test, statement);statement = withRules(method, test, statement);return statement;}?其中最后一个withRules,同时可以看出possiblyExpectingExceptions,withPotentialTimeout,withBefores,withAfters被不推荐使用.其实他们几个都可以采用Rule的方式现实,这也是不推荐使用的主要原因.
?
具体的Rule相关的源代码:
private Statement withRules(FrameworkMethod method, Object target,Statement statement) {List testRules = getTestRules(target);Statement result = statement;result = withMethodRules(method, testRules, target, result);result = withTestRules(method, testRules, result);return result;}private Statement withMethodRules(FrameworkMethod method,List<TestRule> testRules, Object target, Statement result) {for (MethodRule each : getMethodRules(target)) {if (!(testRules.contains(each))) {result = each.apply(result, method, target);}}return result;}private List<MethodRule> getMethodRules(Object target) {return rules(target);}protected List<MethodRule> rules(Object target) {return getTestClass().getAnnotatedFieldValues(target, Rule.class,MethodRule.class);}private Statement withTestRules(FrameworkMethod method,List<TestRule> testRules, Statement statement) {return new RunRules(statement, testRules, describeChild(method));}protected List<TestRule> getTestRules(Object target) {List result = getTestClass().getAnnotatedMethodValues(target,Rule.class, TestRule.class);result.addAll(getTestClass().getAnnotatedFieldValues(target,Rule.class, TestRule.class));return result;}?
可以看出Rule不仅有类级别的还有方法的级别的.
?
?