5.1 Drools约束评分测试-一一网

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前情提示

至此我们在前几天已经学习了三个实例的学习，相信大家对OptaPlanner有了一个更深的学习。大家会发现这几个例子我们使用的都是Drools来编写约束和评分。在这几个例子的学习，大家会有一个疑问，我们增加或者修改约束，如何测试约束是否生效了，匹配的情况如何？那么今天就来学习下基于Drools方式的约束测试内容。

内容

基于Drools的约束条件有一个单元测试工具，要使用它，首先要添加optaplanner-test.jar，以利用JUnit集成的优势，并使用ScoreVerifier类来测试DRL中的分数规则（或一个约束匹配的增量分数计算器）。例如，我们来看CloudBalance案例，测试这些分数规则：

global HardSoftScoreHolder scoreHolder;

rule "requiredCpuPowerTotal"
    when
        ...
    then
        scoreHolder.addHardConstraintMatch(...);
end

...

rule "computerCost"
    when
        ...
    then
        scoreHolder.addSoftConstraintMatch(...);
end
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实现

对于每个评分规则，创建一个单独的@Test，只测试该评分规则对分数的影响。

CloudBalancingScoreConstraintTest.java

public class CloudBalancingScoreConstraintTest {

    private HardSoftScoreVerifier<CloudBalance> scoreVerifier = new HardSoftScoreVerifier<>(
            SolverFactory.createFromXmlResource(CloudBalancingApp.SOLVER_CONFIG));

    @Test
    public void requiredCpuPowerTotal() {
        ......
    }

    @Test
    public void requiredMemoryTotal() {
        ......

    @Test
    public void requiredNetworkBandwidthTotal() {
        ......
    }

    @Test
    public void computerCost() {
        CloudComputer c1 = new CloudComputer(1L, 1, 1, 1, 200);
        CloudComputer c2 = new CloudComputer(2L, 1, 1, 1, 30);
        CloudComputer c3 = new CloudComputer(3L, 1, 1, 1, 4);
        CloudProcess p1 = new CloudProcess(1L, 5, 5, 5);
        CloudProcess p2 = new CloudProcess(2L, 5, 5, 5);
        CloudProcess p3 = new CloudProcess(3L, 5, 5, 5);
        CloudBalance solution = new CloudBalance(0L,
                Arrays.asList(c1, c2, c3),
                Arrays.asList(p1, p2, p3));
        scoreVerifier.assertSoftWeight("computerCost", 0, solution);
        p1.setComputer(c1);
        p2.setComputer(c1);
        scoreVerifier.assertSoftWeight("computerCost", -200, solution);
        p3.setComputer(c3);
        scoreVerifier.assertSoftWeight("computerCost", -204, solution);
    }

}
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可以看到，如果我们测试某一个规则，最好单独增加一个方法进行测试。

测试方法

我们来看这一个约束测试：

 @Test
    public void computerCost() {
        CloudComputer c1 = new CloudComputer(1L, 1, 1, 1, 200);
        CloudComputer c2 = new CloudComputer(2L, 1, 1, 1, 30);
        CloudComputer c3 = new CloudComputer(3L, 1, 1, 1, 4);
        CloudProcess p1 = new CloudProcess(1L, 5, 5, 5);
        CloudProcess p2 = new CloudProcess(2L, 5, 5, 5);
        CloudProcess p3 = new CloudProcess(3L, 5, 5, 5);
        CloudBalance solution = new CloudBalance(0L,
                Arrays.asList(c1, c2, c3),
                Arrays.asList(p1, p2, p3));
        scoreVerifier.assertSoftWeight("computerCost", 0, solution);
        p1.setComputer(c1);
        p2.setComputer(c1);
        scoreVerifier.assertSoftWeight("computerCost", -200, solution);
        p3.setComputer(c3);
        scoreVerifier.assertSoftWeight("computerCost", -204, solution);
    }
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测试步骤

首先我们需要new一个Solution对象，CloudBalance案例中的Solution类为CloudBalance.java。然后进行数据初始化。

CloudProcess是一个PlanningEntity，其中的computer属性是PlanningVariable，我们可以通过修改这个变量后，通过assertSoftWeight断言方法来测试结果是否符合我们的预期。

步骤1：初始化Progress未分配Computer的，其成本为0；

步骤2：p1和p2线程分配Computer中c1的机器，其成本为-200元；

步骤3：p3线程分配Computer中c3的机器，其成本为-204元；

我们执行一下看看结果：

com.intellij.rt.execution.junit.JUnitStarter -ideVersion5 -junit5 org.optaplanner.examples.cloudbalancing.solver.CloudBalancingScoreConstraintTest,computerCost

Process finished with exit code 0
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此时我们修改一行：

......
scoreVerifier.assertSoftWeight("computerCost", 0, solution);
p1.setComputer(c1);
p2.setComputer(c1);
scoreVerifier.assertSoftWeight("computerCost", 0, solution); // 200 -> 0
......
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此时我们再来看结果：

org.opentest4j.AssertionFailedError: 
Expected :0
Actual   :-200
<Click to see difference>
org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.submit(SameThreadHierarchicalTestExecutorService.java:32)
	at org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutor.execute(HierarchicalTestExecutor.java:57)
	at org.junit.platform.engine.support.hierarchical.HierarchicalTestEngine.execute(HierarchicalTestEngine.java:51)
	at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:229)
	at org.junit.platform.launcher.core.DefaultLauncher.lambda$execute$6(DefaultLauncher.java:197)
	at org.junit.platform.launcher.core.DefaultLauncher$$Lambda$132/695682681.accept(Unknown Source)
	at org.junit.platform.launcher.core.DefaultLauncher.withInterceptedStreams(DefaultLauncher.java:211)
	at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:191)
	at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:128)
	at com.intellij.junit5.JUnit5IdeaTestRunner.startRunnerWithArgs(JUnit5IdeaTestRunner.java:69)
	at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:47)
	at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:242)
	at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70)

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