Difference Between @Resource, @Autowired and @Inject in Spring Injection

1. @Resource – Defined in the javax.annotation package and part of Java
2. @Inject – Defined in the javax.inject package and part of Java
3. @Autowired – Defined in the package org.springframework.bean.factory and part of Spring framework.

@Autowired and Inject behaves exactly same

Order is  -> byType -> @Qualifier ->byName

@Service

public class FruitProcessor {

@Autowired

private Fruit fruit;

//private Fruit fruit;

//private Fruit fruit;

}

@Service

public class FruitProcessor {

@Resource

@Qualifier("mango")

private Fruit apple;

//private Fruit fruit;

//private Fruit fruit;

@Override

public String toString() {

return "FruitProcessor [apple=" + apple + "]";

}

}

output is :

FruitProcessor [apple=Apple [taste=sour, getColor()=null]]

Means still we mentioned @Qualifier("mango") but it is autowired by

byName

Because Autowiring  order for @Resource  is -byName -> byType->@Qualifier

Summary :-

@Autowired and @Inject

1. Matches by Type
2. Restricts by Qualifiers
3. Matches by Name

@Resource

1. Matches by Name
2. Matches by Type
3. Restricts by Qualifiers (ignored if match is found by name)