使用Cobertura进行单元测试很慢

Question

我最近将Cobertura集成到我的Ant构建脚本中，我想知道我是否做对了，因为它大大降低了运行单元测试所需的时间。

下面是一个示例控制台输出:

...
[junit] Running gov.nyc.doitt.gis.webmap.strategy.markup.ViewportDeterminingMarkupStrategyTest
[junit] Tests run: 5, Failures: 0, Errors: 0, Time elapsed: 0.38 sec
[junit] Flushing results...
[junit] Flushing results done
[junit] Cobertura: Loaded information on 282 classes.
[junit] Cobertura: Saved information on 282 classes.
[junit] Running gov.nyc.doitt.gis.webmap.strategy.markup.VisibleFeatureTypesMarkupInfoTest
[junit] Tests run: 1, Failures: 0, Errors: 0, Time elapsed: 0.434 sec
[junit] Flushing results...
[junit] Flushing results done
[junit] Cobertura: Loaded information on 282 classes.
[junit] Cobertura: Saved information on 282 classes.
[junit] Running gov.nyc.doitt.gis.webmap.strategy.markup.basemap.BasemapByViewportStrategyTest
[junit] Tests run: 3, Failures: 0, Errors: 0, Time elapsed: 2.016 sec
[junit] Flushing results...
[junit] Flushing results done
[junit] Cobertura: Loaded information on 282 classes.
[junit] Cobertura: Saved information on 282 classes.
[junit] Running gov.nyc.doitt.gis.webmap.strategy.markup.basemap.BasemapByZoomLevelAndCenterPointStrategyTest
[junit] Tests run: 4, Failures: 0, Errors: 0, Time elapsed: 1.853 sec
[junit] Flushing results...
[junit] Flushing results done
[junit] Cobertura: Loaded information on 282 classes.
[junit] Cobertura: Saved information on 282 classes.
...

每次测试结束后，Cobertura说:

[junit] Cobertura: Loaded information on 282 classes.
[junit] Cobertura: Saved information on 282 classes.
...

下面是我的Ant构建脚本中的单元测试任务:

    <target name="unit-test" depends="compile-unit-test">
    <delete dir="${reports.xml.dir}" />
    <delete dir="${reports.html.dir}" />
    <mkdir dir="${reports.xml.dir}" />
    <mkdir dir="${reports.html.dir}" />
    <junit fork="yes" dir="${basedir}" failureProperty="test.failed" printsummary="on">
        <!--
                Note the classpath order: instrumented classes are before the
                original (uninstrumented) classes.  This is important.
            -->
        <classpath location="${instrumented.dir}" />
        <classpath refid="test-classpath" />
        <formatter type="xml" />
        <test name="${testcase}" todir="${reports.xml.dir}" if="testcase" />
        <batchtest todir="${reports.xml.dir}" unless="testcase">
            <fileset dir="TestSource">
                <include name="**/*Test.java" />
                <exclude name="**/XmlTest.java" />
                <exclude name="**/ElectedOfficialTest.java" />
                <exclude name="**/ThematicManagerFixturesTest.java" />
            </fileset>
        </batchtest>
    </junit>
</target>

我的设置和输出看起来正确吗?单元测试单独运行时需要2.234秒，而在使用Cobertura的构建脚本中运行时需要3分钟，这是否正常?

Answer 1

来自cobertura-anttask reference:

出于同样的原因，如果您使用的是ant 1.6.2或更高版本，那么您需要可能想要设置forkmode="once"这将导致只有一个JVM被占用为您的所有JUnit测试开始，并将减少的开销Cobertura每次在JVM上读/写覆盖率数据文件启动/停止。