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1. showInfo() doesn't need to depend on Student, which can use other types of objects that also contain name and age (eg: Teacher) instead of binding specific implementation

2. Easer to test : Pass required parameters only doesn't need to new a Student object first to test showInfo(),or we may replace Student with other objects that also has name and age such as Teacher at the calling client side, more likely a unit test instead of integration test

3. Looser coupling : Removing Student class doesn't require me to modify showInfo() to recompile

4. More reuseable showInfo() : I don't need to create another showInfo() method when I need another object (eg: I don't need to add

1. showInfo() doesn't need to depend on Student, which can use other types of objects that also contain name and age (eg: Teacher) instead of binding specific implementation

2. Easier to test : Pass required parameters only doesn't need to new a Student object first to test showInfo(),or we may replace Student with other objects that also has name and age such as Teacher at the calling client side, more likely a unit test instead of integration test

3. Looser coupling : Removing Student class doesn't require me to modify showInfo() to recompile

4. More reuseable showInfo() : I don't need to create another showInfo() method when I need another object (eg: I don't need to add

1. "Non dependency injection" has less parameters in the Client constructor, which fits the motivation of "Preserve whole object" that shorter parameter list is better

2. In "Non dependency injection", adding new components don't need to modify the parameter list of constructors,eg:

but the "Dependency injection" version needs to add a new parameter:

1. "Non dependency injection" has less parameters in the Client constructor, which fits the motivation of "Preserve whole object" that shorter parameter list is better

2. In "Non dependency injection", adding new components doesn't need to modify the parameter list in constructors,eg:

but the "Dependency injection" version needs to add a new parameter to the constructor:

which "Non dependency injection" fits the situation that passing "Studnet" instead of "name" and "age" because adding new properties don't need to modify parameter list

, as if in showInfo() repeating getters:

instead of

which "Non dependency injection" fits the situation of "preserve whole object is better" that passing "Studnet" instead of "name" and "age" allows us adding new properties (eg: dateOfBirth) without modify the parameter list

, as if in "preserve whole object" version that showInfo() types "student" only:

instead of typing getters at each parameter: