SpringBoot implement lazy loading @Lazy

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This link: https://blog.csdn.net/TreeShu321/article/details/102488868

@Lazy Instructions

• In general, Spring container will create all the objects Bean at startup, use @Lazy annotation can be created Bean object delayed until the first use of Bean

Instructions

1, @ Lazy (value = true ): Default is true, does not perform constructor
2, @ Lazy (value = false ): constructor is executed

Spring loaded to take the bean container manner

• @Configuration +@bean

@Configuration
public class BeanConfig {

    @Bean
    @Lazy(value = true)
    public People people() {
        return new People();
    }
}

• @component

@Component
@Lazy(value = true)
public class Cat{

    public Cat() {
        System.out.println("#######小白猫#######);
    }
}

• @import

@Import(value = {Dog.class})

@Lazy(value=false)
public class Dog{
    public Dog() {
        System.out.println("#######大黄狗#######);
    }
}

Sample Code

1, do not use @lazy

/**
 * @author shuliangzhao
 * @Title: MyLazy
 * @ProjectName spring-boot-learn
 * @Description: TODO
 * @date 2019/10/10 19:27
 */
@Component
public class MyLazy {

    public MyLazy() {
        System.out.println("懒加载...");
    }

    public void say() {
        System.out.println("say...");
    }
}

/**
 * @author shuliangzhao
 * @Title: LazyTest
 * @ProjectName spring-boot-learn
 * @Description: TODO
 * @date 2019/10/10 19:31
 */
@RunWith(SpringRunner.class)
@SpringBootTest
public class LazyTest {

    @Autowired
    private MyLazy myLazy;

    @Test
    public void test() {
         myLazy.say();
    }
}

The results:

2, using the lazy

/**
 * @author shuliangzhao
 * @Title: MyLazy
 * @ProjectName spring-boot-learn
 * @Description: TODO
 * @date 2019/10/10 19:27
 */
@Component
@Lazy
public class MyLazy {

    public MyLazy() {
        System.out.println("懒加载...");
    }

    public void say() {
        System.out.println("say...");
    }
}

/**
 * @author shuliangzhao
 * @Title: LazyTest
 * @ProjectName spring-boot-learn
 * @Description: TODO
 * @date 2019/10/10 19:31
 */
@RunWith(SpringRunner.class)
@SpringBootTest
public class LazyTest {

    @Autowired
    private MyLazy myLazy;

    @Test
    public void test() {
         myLazy.say();
    }
}

Results of the: