JMockit使用實例mock某個類的常量值

• 關鍵詞：mock 常量的mock
• 源類清單
  public static class ClassWithConstant {

          private static final Integer ANSWER = 42;

   

          public static final int getAnswer() {

              return ANSWER;

          }

      }
• 單元測試類清單
  public class ClassWithConstantTest {

   

   

      @Test

      public void test() {

          killThreadLocal(ClassWithConstant.class.getName(),"ANSWER");

          Deencapsulation.setField(ClassWithConstant.class, 43);

          assertEquals(43, new ClassWithConstant().getAnswer());

      }

   

      //use reflection to remove the final modifier first

      private void killThreadLocal(String klazzName, String fieldName) {

          try{

          Field field = Class.forName(klazzName).getDeclaredField(fieldName);

          field.setAccessible(true);

          Field modifiersField = Field.class.getDeclaredField("modifiers");

          modifiersField.setAccessible(true);

          int modifiers = modifiersField.getInt(field);

          modifiers &= ~Modifier.FINAL;

          modifiersField.setInt(field, modifiers);

          field.set(null, null);

          }catch(Exception e){

   

          }

  }

  }