java - jmock，每次调用时返回新对象

Question

我正在设置一个模拟对象，每次调用方法 f() 时它应该返回一个新的业务对象。如果我简单地说 returnValue(new BusinessObj())，它将在每次调用时返回相同的引用。如果我不知道 f() 会有多少次调用，即我不能使用 onConsecutiveCalls，我该如何解决这个问题？

Answer 1

您需要声明一个 CustomAction 实例来代替标准的 returnValue 子句:

allowing(mockedObject).f();
will(new CustomAction("Returns new BusinessObj instance") {
  @Override
  public Object invoke(Invocation invocation) throws Throwable {
    return new BusinessObj();
  }
});

下面是一个独立的单元测试来证明这一点:

import org.jmock.Expectations;
import org.jmock.Mockery;
import org.jmock.api.Invocation;
import org.jmock.integration.junit4.JMock;
import org.jmock.integration.junit4.JUnit4Mockery;
import org.jmock.lib.action.CustomAction;
import org.junit.Assert;
import org.junit.Test;
import org.junit.runner.RunWith;

@RunWith(JMock.class)
public class TestClass {

  Mockery context = new JUnit4Mockery();

  @Test
  public void testMethod() {
    final Foo foo = context.mock(Foo.class);

    context.checking(new Expectations() {
      {
        allowing(foo).f();
        will(new CustomAction("Returns new BusinessObj instance") {
          @Override
          public Object invoke(Invocation invocation) throws Throwable {
            return new BusinessObj();
          }
        });
      }
    });

    BusinessObj obj1 = foo.f();
    BusinessObj obj2 = foo.f();

    Assert.assertNotNull(obj1);
    Assert.assertNotNull(obj2);
    Assert.assertNotSame(obj1, obj2);
  }

  private interface Foo {
    BusinessObj f();
  }

  private static class BusinessObj {
  }
}