Differ

• 对比逻辑
• 应用示例

对比逻辑

1. 如果两者是基本类型，则直接使用 Object.equals 执行对比。
2. 如果两者是集合类型，则直接使用 Object.deepEquals 执行对比。
3. 否则，基于 Getter 或 Field 选择，通过反射获取属性值，执行对比。
4. 支持对比不同类型的对象，默认仅对比二者共有的属性。

Arrays.deepEquals looks really deep. From the source, we could understand that Arrays.deepEquals:

1. Loops through the input arrays, gets each pair
2. Analyses the type of each pair
3. Delegates the equal deciding logic to one of the overloaded Arrays.equals if they are one of the primitive arrays
4. Delegates recursively to Arrays.deepEquals if it is an Object array
5. Calls the respective object’s equals, for any other object

如果以上功能不能满足的需要，可以尝试使用 java-object-differ。

应用示例

String val1 = "val1";
String val2 = "val2";
List<Integer> list1 = Arrays.asList(1,2);
List<Integer> list2 = Arrays.asList(3,4);
Person person1 = new Person("Anna", 22);
Person person2 = new Person("Luna", 23);

Differ fieldDiffer = Differ.builder()
    .include()
    .exclude()
    .onlyBothExist(true)
    .baseField();

Differ getterDiffer = Differ.builder()
    .include()
    .exclude()
    .onlyBothExist(true)
    .baseGetter();

List<FieldInfo> diff1 = fieldDiffer.diff(val1, val2); 
List<FieldInfo> diff2 = fieldDiffer.diff(list1, list2); 
List<FieldInfo> diff3 = fieldDiffer.diff(person1, person2); 
List<FieldInfo> diff4 = getterDiffer.diff(person1, person2);