java config_error ai_generated true

无法实例化 @InjectMocks 字段 'service'，类型为 'class com.example.MyService'

org.mockito.exceptions.base.MockitoException: Cannot instantiate @InjectMocks field named 'service' of type 'class com.example.MyService'

ID: java/mockito-injectmocks-failure

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80%修复率
87%置信度
0证据数
2024-10-05首次发现

版本兼容性

版本状态引入弃用备注
8+ active — — —

根因分析

@InjectMocks 需要无参构造函数或构造函数注入，但类缺少无参构造函数或有歧义的构造函数。

English

@InjectMocks requires a no-arg constructor or constructor injection, but class lacks one or has ambiguous constructors.

generic

解决方案

  1. 90% 成功率 Provide a no-arg constructor in production class 
    public MyService() {
    // default constructor
}
  2. 85% 成功率 Use manual construction with mocks 
    MyService service = new MyService(mockDep1, mockDep2);

无效尝试

常见但无效的做法:

  1. Adding @InjectMocks to a field with private constructor 70% 失败

    Mockito cannot instantiate the class.

  2. Using @Spy on the same field 50% 失败

    Spy requires an instance; @InjectMocks is for creating instances.