如何在Mockito中更改字符串的默认返回值？ [英] How do I change the default return value for Strings in Mockito?

问题描述

2010年的这个问题暗示了我正在尝试做的事情。

我正在进行单元测试，该测试运行的代码需要许多模拟对象才能完成它需要做的事情（测试HTML + PDF渲染） 。为了使这个测试成功，我需要生成许多模拟对象，并且每个对象最终都会将一些String数据返回给正在测试的代码。

I'm working on a unit test which exercises code that requires many mocked objects to do what it needs to do (testing HTML + PDF rendering). For this test to be successful I need many mocked objects to be generated and each of these objects ultimately return some String data to the code being tested.

我认为我可以通过实现我自己的 Answer 类或 IMockitoConfiguration 来实现这一点，但我不知道如何实现它们只会影响返回字符串的方法。

I think I can do this by implementing either my own Answer class or IMockitoConfiguration, but I am not sure how to implement those so they only affect methods which return Strings.

我觉得下面的代码接近我想要的。它抛出一个强制转换异常， java.lang.ClassCastException：java.lang.String无法强制转换为com.mypackage.ISOCountry 。我想这意味着我需要以某种方式默认或限制 Answer 只影响 String 的默认值。

I feel that the following code is close to what I want. It throws a cast exception, java.lang.ClassCastException: java.lang.String cannot be cast to com.mypackage.ISOCountry. I think this means I need to somehow default or limit the Answer to only affect the defaults for String.

private Address createAddress(){
    Address address = mock(Address.class, new StringAnswer() );

    /* I want to replace repetitive calls like this, with a default string. 
    I just need these getters to return a String, not a specific string.

    when(address.getLocality()).thenReturn("Louisville");
    when(address.getStreet1()).thenReturn("1234 Fake Street Ln.");
    when(address.getStreet2()).thenReturn("Suite 1337");
    when(address.getRegion()).thenReturn("AK");
    when(address.getPostal()).thenReturn("45069");   
    */

    ISOCountry isoCountry = mock(ISOCountry.class);
    when(isoCountry.getIsocode()).thenReturn("US");
    when(address.getCountry()).thenReturn(isoCountry);

    return address;
}

//EDIT: This method returns an arbitrary string
private class StringAnswer implements Answer<Object> {
    @Override
    public Object answer(InvocationOnMock invocation) throws Throwable {
        String generatedString = "Generated String!";
           if( invocation.getMethod().getReturnType().isInstance( generatedString )){
               return generatedString;
           }
           else{
               return Mockito.RETURNS_DEFAULTS.answer(invocation);
           }
       }
}

我如何设置Mockito默认情况下为返回String的模拟类上的方法返回生成的String？ 我找到了关于此问题的这一部分的解决方案

How can I set up Mockito to return a generated String by default for methods on a mocked class which return String? I found a solution to this part of the question on SO

对于额外的积分，如何将生成的值设为一个字符串，其格式为 Class.methodName ？例如Address.getStreet1（）而不仅仅是一个随机字符串？

For extra points, how can I make that generated value be a String which is in the form Class.methodName? For example "Address.getStreet1()" instead of just a random String?

推荐答案

我能够完全回答我自己的问题。

I was able to completely answer my own question.

在这个例子中，生成了路易斯维尔地区的地址，而其他字段看起来像地址。 getStreet1（）;。

In this example an address with the Locality of Louisville is generated while the other fields look like "address.getStreet1();".

private Address createAddress(){
    Address address = mock(Address.class, new StringAnswer() );

    when(address.getLocality()).thenReturn("Louisville");

    ISOCountry isoCountry = mock(ISOCountry.class);
    when(isoCountry.getIsocode()).thenReturn("US");
    when(address.getCountry()).thenReturn(isoCountry);

    return address;
}

private class StringAnswer implements Answer<Object> {
    @Override
    public Object answer(InvocationOnMock invocation) throws Throwable {
           if( invocation.getMethod().getReturnType().equals(String.class)){
               return invocation.toString();
           }
           else{
               return Mockito.RETURNS_DEFAULTS.answer(invocation);
           }
       }
}

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