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@规则声明导致调试尝试出错

junit-rule junit groovy eclipse java

0

Gangnus · 技术社区 · 13 年前

groovy JUnit测试类只有一个静态声明:

@Rule
public static ErrorCollector errorCollector;

尝试在调试模式下启动测试后,会引发异常:

java.lang.NullPointerException
at org.junit.runners.BlockJUnit4ClassRunner.withRules(BlockJUnit4ClassRunner.java:354)
at org.junit.runners.BlockJUnit4ClassRunner.methodBlock(BlockJUnit4ClassRunner.java:270)
at org.junit.runners.BlockJUnit4ClassRunner.runNotIgnored(BlockJUnit4ClassRunner.java:79)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:71)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:49)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:193)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:52)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:191)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:42)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:184)
at org.junit.runners.ParentRunner.run(ParentRunner.java:236)
at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:49)
at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)

在代码中的任何一行开始之前都会引发异常。如果我去掉“@Rule”这个词,那么测试运行正常(至少从一开始)

进口产品包括:

import static org.hamcrest.CoreMatchers.*;
import org.hamcrest.Matcher;
import static org.hamcrest.Matchers.*;

import org.junit.Rule;
import org.junit.rules.ErrorCollector;
import org.junit.Test;
import static org.junit.Assert.*;
import org.junit.Before;

import groovy.util.slurpersupport.NodeChild
import groovy.xml.MarkupBuilder
import groovy.xml.StreamingMarkupBuilder
import groovy.xml.XmlUtil
import org.codehaus.groovy.tools.xml.DomToGroovy

import org.joda.time.DateTime
import org.w3c.dom.Document;

import java.util.concurrent.Callable;

JUnit版本4.8.2

Eclipse版本:3.6

Java版本:1.6.41

请问我应该在哪里查找问题?

2 回复 | 直到 13 年前

1

3

Jose Renato 13 年前

正如您在 ErrorCollector javadoc ,必须创建一个实例才能使用它,如下所示:

    @Rule
    public ErrorCollector collector= new ErrorCollector();

2

0

Gangnus 13 年前

这似乎是Runner中的一个bug:

//Correct variants:
@Rule
public ErrorCollector collector1= new ErrorCollector();


public ErrorCollector collector2= null;
@Rule
collector2= new ErrorCollector();

public ErrorCollector collector3;
@Rule
collector3= new ErrorCollector();


// incorrect variants:
@Rule
public ErrorCollector collector4= null;

@Rule
public ErrorCollector collector5;

@Rule
public ErrorCollector collector5=somethingThatIsNotRule;

@Rule
public ErrorCollector collector5=anotherRule;

//BUT:
//the runner takes the following, and runs it without problems, too:

public ErrorCollector collector6= null;
{
  @Rule
  collector6= null;
}

因此,运行程序在构建测试之前会进行过多的检查。