{"id":557,"date":"2021-09-24T19:07:29","date_gmt":"2021-09-24T11:07:29","guid":{"rendered":"https:\/\/explause.com\/?p=557"},"modified":"2021-09-24T19:07:29","modified_gmt":"2021-09-24T11:07:29","slug":"%e5%9f%ba%e4%ba%8e%e6%b3%a8%e8%a7%a3%e7%9a%84%e5%ae%b9%e5%99%a8%e9%85%8d%e7%bd%ae","status":"publish","type":"post","link":"https:\/\/devdoge.org\/?p=557","title":{"rendered":"\u57fa\u4e8e\u6ce8\u89e3\u7684\u5bb9\u5668\u914d\u7f6e"},"content":{"rendered":"\n

\u6ce8\u89e3\u4e00\u5b9a\u6bd4xml\u914d\u7f6e\u597d\u5417\uff1f
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Spring\u90fd\u63a5\u53d7\uff0c\u751a\u81f3\u53ef\u4ee5\u6df7\u7528\u3002
\u6ce8\u89e3\u5728xml\u4e4b\u524d\u88ab\u89e3\u6790\uff0c\u6240\u4ee5xml\u914d\u7f6e\u4f1a\u8986\u76d6\u6ce8\u89e3\u914d\u7f6e\u3002<\/p>\n\n\n\n

\u4f7f\u7528\u6ce8\u89e3\u53ea\u9700\u8981\u5728xml\u914d\u7f6e\u6587\u4ef6\u6539\u6210\uff1a<\/p>\n\n\n\n

<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n<beans xmlns=\"http:\/\/www.springframework.org\/schema\/beans\"\n    xmlns:xsi=\"http:\/\/www.w3.org\/2001\/XMLSchema-instance\"\n    xmlns:context=\"http:\/\/www.springframework.org\/schema\/context\"\n    xsi:schemaLocation=\"http:\/\/www.springframework.org\/schema\/beans\n        https://www.springframework.org\/schema\/beans\/spring-beans.xsd\n        http:\/\/www.springframework.org\/schema\/context\n        https:\/\/www.springframework.org\/schema\/context\/spring-context.xsd\">\n\n    <context:annotation-config\/>\n\n<\/beans><\/code><\/pre>\n\n\n\n
<context:annotation-config\/<\/code>>\u5143\u7d20\u9690\u5f0f\u6ce8\u518c\u4ee5\u4e0bpost-processors:<\/p>\n\n\n\n
ConfigurationClassPostProcessor<\/strong><\/code><\/td><\/tr>
AutowiredAnnotationBeanPostProcessor<\/strong><\/code><\/td><\/tr>
CommonAnnotationBeanPostProcessor<\/strong><\/code><\/td><\/tr>
PersistenceAnnotationBeanPostProcessor<\/strong><\/code><\/td><\/tr>
EventListenerMethodProcessor<\/strong><\/code><\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
<context:annotation-config\/<\/code>>\u5143\u7d20\u53ea\u4f1a\u5728\u540c\u4e00\u4e2a\u5bb9\u5668\u5185\u5bfb\u627ebean\uff0c
\u610f\u601d\u662fApplicationContext<\/strong>\u4e0d\u4f1a\u5728WebApplicationContext<\/strong>\u91cc\u9762\u5bfb\u627ebean\u3002<\/p>\n\n\n\n
@Required\u6ce8\u89e3\uff1a\u7528\u4e8ebean\u7684setter\u65b9\u6cd5\u3002<\/strong>
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\uff08\u54a6\uff0c\u4e3a\u4ec0\u4e48\u662f\u7a7a\u6307\u9488\u5f02\u5e38\u4e0d\u662f\u7a7a\u5f15\u7528\u5f02\u5e38\uff1f\uff09
\u8fd8\u9700\u8981\u5c06RequiredAnnotationBeanPostProcessor<\/strong><\/code>\u6ce8\u518c\u6210bean\u624d\u80fd\u751f\u6548\u3002
\u5df2\u5e9f\u5f03\uff0c\u53ef\u4ee5\u901a\u8fc7\u6784\u9020\u5668\u53c2\u6570\u6ce8\u5165\u786e\u4fdd\u5f3a\u5236\u6267\u884c\u3002<\/p>\n\n\n\n
@Autowired<\/strong><\/code>\u6ce8\u89e3\uff1a\u53ef\u4ee5\u7528\u4e8e\u6784\u9020\u5668\uff1a<\/strong><\/p>\n\n\n\n
public class MovieRecommender {\n\n    private final CustomerPreferenceDao customerPreferenceDao;\n\n    @Autowired\n    public MovieRecommender(CustomerPreferenceDao customerPreferenceDao) {\n        this.customerPreferenceDao = customerPreferenceDao;\n    }\n\n    \/\/ ...\n}<\/code><\/pre>\n\n\n\n
\u4e5f\u53ef\u4ee5\u7528\u4e8e\u6709\u591a\u4e2a\u53c2\u6570\u7684\u65b9\u6cd5\uff1a<\/p>\n\n\n\n
public class MovieRecommender {\n\n    private MovieCatalog movieCatalog;\n\n    private CustomerPreferenceDao customerPreferenceDao;\n\n    @Autowired\n    public void prepare(MovieCatalog movieCatalog,\n            CustomerPreferenceDao customerPreferenceDao) {\n        this.movieCatalog = movieCatalog;\n        this.customerPreferenceDao = customerPreferenceDao;\n    }\n\n    \/\/ ...\n}<\/code><\/pre>\n\n\n\n
\u4eceSpring4.3\u5f00\u59cb\uff0c\u5728\u53ea\u6709\u4e00\u4e2a\u6784\u9020\u5668\u7684\u60c5\u51b5\u4e0b\u6ca1\u5fc5\u8981\u6dfb\u52a0\u3002
\u6709\u591a\u4e2a\u6784\u9020\u5668\u4f46\u662f\u6ca1\u6709\u9ed8\u8ba4\u6784\u9020\u5668\u5c31\u9700\u8981\u6dfb\u52a0\u6b64\u6ce8\u89e3\u544a\u8bc9\u5bb9\u5668\u7528\u54ea\u4e2a\u3002<\/p>\n\n\n\n
\u4e5f\u53ef\u4ee5\u5c06\u6b64\u6ce8\u89e3\u7528\u4e8esetter\u65b9\u6cd5\uff1a<\/p>\n\n\n\n
public class SimpleMovieLister {\n\n    private MovieFinder movieFinder;\n\n    @Autowired\n    public void setMovieFinder(MovieFinder movieFinder) {\n        this.movieFinder = movieFinder;\n    }\n\n    \/\/ ...\n}<\/code><\/pre>\n\n\n\n
\u6b64\u6ce8\u89e3\u751a\u81f3\u53ef\u4ee5\u540c\u65f6\u7528\u4e8e\u65b9\u6cd5\u548c\u7528\u4e8e\u53d8\u91cf\uff1a<\/p>\n\n\n\n
public class MovieRecommender {\n\n    private final CustomerPreferenceDao customerPreferenceDao;\n\n    @Autowired\n    private MovieCatalog movieCatalog;\n\n    @Autowired\n    public MovieRecommender(CustomerPreferenceDao customerPreferenceDao) {\n        this.customerPreferenceDao = customerPreferenceDao;\n    }\n\n    \/\/ ...\n}<\/code><\/pre>\n\n\n\n
\u751a\u81f3\u53ef\u4ee5\u8ba9Spring\u5c06\u6240\u6709\u7c7b\u578b\u7b26\u5408\u7684bean\u6253\u5305\u6210\u4e00\u4e2a\u6570\u7ec4\uff1a<\/p>\n\n\n\n
public class MovieRecommender {\n\n    @Autowired\n    private MovieCatalog[] movieCatalogs;\n\n    \/\/ ...\n}<\/code><\/pre>\n\n\n\n
\u6570\u7ec4\u91cc\u7684bean\u53ef\u4ee5\u901a\u8fc7\u5b9e\u73b0org.springframework.core.Ordered<\/strong>\u63a5\u53e3\u6216@Order\/@Priority<\/strong>\u5b8c\u6210\u6392\u5e8f\u3002
\u5426\u5219\u5c31\u6309\u5b9a\u4e49\u987a\u5e8f\u6dfb\u52a0\u8fdb\u6570\u7ec4\u3002<\/p>\n\n\n\n
\u5f3a\u7c7b\u578bMap\u540c\u6837\u53ef\u4ee5\uff0ckey\u5c31\u662fbean\u7684\u540d\u5b57\u3002<\/p>\n\n\n\n
@<\/strong>Autowired<\/strong><\/code>\u6ce8\u89e3<\/strong>\u9ed8\u8ba4\u5f3a\u5236\u6ce8\u5165\uff0c\u5982\u679c\u6ca1\u6709\u5339\u914d\uff0c\u5c31\u4f1a\u62a5\u5f02\u5e38\u3002
\u53ef\u901a\u8fc7\u8bbe\u7f6erequired<\/strong>\u5c5e\u6027\u8868\u793a\u975e\u5fc5\u9700\uff1a<\/p>\n\n\n\n
public class SimpleMovieLister {\n\n    private MovieFinder movieFinder;\n\n    @Autowired(required = false)\n    public void setMovieFinder(MovieFinder movieFinder) {\n        this.movieFinder = movieFinder;\n    }\n\n    \/\/ ...\n}<\/code><\/pre>\n\n\n\n
\u5bf9\u4e8e\u6784\u9020\u5668\u548c\u5de5\u5382\u65b9\u6cd5required<\/strong>\u5c5e\u6027\u7684\u610f\u4e49\u4f1a\u6709\u70b9\u4e0d\u4e00\u6837\uff1a\u5bf9\u4e8e\u542b\u6709\u591a\u4e2abean\u7684\u6ce8\u5165\u70b9\uff0c
\u5982arrays, collections, maps\uff0c\u5f53\u6ca1\u6709\u5408\u9002\u7684bean\u65f6\u4f1a\u89e3\u6790\u6210\u7a7a\u7684\u5b9e\u4f8b\u3002
\u53ea\u6709\u4e00\u4e2a\u6784\u9020\u65b9\u6cd5\u53ef\u4ee5\u88ab\u8bbe\u7f6e\u6210@Autowired(required = true)<\/strong>\uff0c
\u5982\u679c\u8981\u58f0\u660e\u591a\u4e2a\u6784\u9020\u5668\uff0c\u5c31\u8981\u6539\u6210@Autowired(required = false)<\/strong>\uff0c\u4ee5\u4f5c\u4e3a\u5019\u9009\u3002<\/p>\n\n\n\n
\u4e5f\u53ef\u4ee5\u901a\u8fc7Java 8 \u7684java.util.Optional\u5de5\u5177\u5b9e\u73b0non-required\u3002
Spring 5.0\u4ee5\u4e0a\u4e5f\u53ef\u4ee5\u901a\u8fc7@Nullable<\/strong>\u5b9e\u73b0\u3002<\/p>\n\n\n\n
@Autowired<\/code>\uff0c@Inject<\/code>\uff0c@Value<\/code>\uff0c\u548c@Resource<\/code>\u6ce8\u89e3<\/strong>\u90fd\u662f\u901a\u8fc7BeanPostProcessor<\/strong>\u5b9e\u73b0\u7684\uff0c\u4e0d\u53ef\u4ee5\u5c06\u8fd9\u4e9b\u6ce8\u89e3\u7528\u4e8eBeanPostProcessor<\/strong>\u6216BeanFactoryPostProcessor<\/strong>\u7c7b\u578b\u3002<\/p>\n\n\n\n
\u901a\u8fc7<\/strong>@Primary<\/strong><\/code>\u8fdb\u884c\u66f4\u597d\u7684\u8c03\u6574\uff1a<\/strong><\/p>\n\n\n\n
\u5982\u679c\u6709\u591a\u4e2a\u5339\u914d\u9879\u65f6\u5c31\u9009\u6709\u6b64\u6ce8\u89e3\u7684\u90a3\u4e2a\uff1a<\/p>\n\n\n\n
@Configuration\npublic class MovieConfiguration {\n\n    @Bean\n    @Primary\n    public MovieCatalog firstMovieCatalog() { ... }\n\n    @Bean\n    public MovieCatalog secondMovieCatalog() { ... }\n\n    @Autowired\n    private MovieCatalog movieCatalog;\n}<\/code><\/pre>\n\n\n\n
\u4e0a\u9762\u7684\u4f8b\u5b50\u4e2dfirstMovieCatalog<\/strong>\u65b9\u6cd5\u80dc\u51fa\u3002<\/p>\n\n\n\n
\u5728xml\u914d\u7f6e\u6587\u4ef6\u4e2d\u5bf9\u5e94<bean\/>\u5143\u7d20\u7684primary<\/strong>\u5c5e\u6027\uff0c\u503c\u4e3atrue\uff1a<\/p>\n\n\n\n
<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n<beans xmlns=\"http:\/\/www.springframework.org\/schema\/beans\"\n    xmlns:xsi=\"http:\/\/www.w3.org\/2001\/XMLSchema-instance\"\n    xmlns:context=\"http:\/\/www.springframework.org\/schema\/context\"\n    xsi:schemaLocation=\"http:\/\/www.springframework.org\/schema\/beans\n        https://www.springframework.org\/schema\/beans\/spring-beans.xsd\n        http:\/\/www.springframework.org\/schema\/context\n        https:\/\/www.springframework.org\/schema\/context\/spring-context.xsd\">\n\n    <context:annotation-config\/>\n\n    <bean class=\"example.SimpleMovieCatalog\" primary=\"true\"\/>\n\n    <bean class=\"example.SimpleMovieCatalog\"\/>\n\n    <bean id=\"movieRecommender\" class=\"example.MovieRecommender\"\/>\n\n<\/beans><\/code><\/pre>\n\n\n\n
\u901a\u8fc7<\/strong>@Qualifier<\/strong><\/code>\u8fdb\u884c\u66f4\u597d\u7684\u8c03\u6574\uff1a<\/strong><\/p>\n\n\n\n
\u5982\u679c\u5728\u6709@Primary<\/strong><\/code>\u7684bean\u53ef\u7528\u65f6\u60f3\u9009\u522b\u7684bean\uff0c\u53ef\u7528\u5b83\u7f29\u5c0f\u5339\u914d\u8303\u56f4\uff1a<\/p>\n\n\n\n
public class MovieRecommender {\n\n    @Autowired\n    @Qualifier(\"main\")\n    private MovieCatalog movieCatalog;\n\n    \/\/ ...\n}<\/code><\/pre>\n\n\n\n
\u4e5f\u53ef\u4ee5\u7528\u4e8e\u6784\u9020\u5668\u53c2\u6570\u6216\u8005\u65b9\u6cd5\u53c2\u6570\uff1a<\/p>\n\n\n\n
public class MovieRecommender {\n\n    private MovieCatalog movieCatalog;\n\n    private CustomerPreferenceDao customerPreferenceDao;\n\n    @Autowired\n    public void prepare(@Qualifier(\"main\") MovieCatalog movieCatalog,\n            CustomerPreferenceDao customerPreferenceDao) {\n        this.movieCatalog = movieCatalog;\n        this.customerPreferenceDao = customerPreferenceDao;\n    }\n\n    \/\/ ...\n}<\/code><\/pre>\n\n\n\n
\u5728xml\u914d\u7f6e\u6587\u4ef6\u4e2d\u4f7f\u7528<bean\/>\u5143\u7d20\u7684<qualifier\/>\u5b50\u5143\u7d20\uff1a<\/p>\n\n\n\n
<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n<beans xmlns=\"http:\/\/www.springframework.org\/schema\/beans\"\n    xmlns:xsi=\"http:\/\/www.w3.org\/2001\/XMLSchema-instance\"\n    xmlns:context=\"http:\/\/www.springframework.org\/schema\/context\"\n    xsi:schemaLocation=\"http:\/\/www.springframework.org\/schema\/beans\n        https://www.springframework.org\/schema\/beans\/spring-beans.xsd\n        http:\/\/www.springframework.org\/schema\/context\n        https:\/\/www.springframework.org\/schema\/context\/spring-context.xsd\">\n\n    <context:annotation-config\/>\n\n    <bean class=\"example.SimpleMovieCatalog\">\n        <qualifier value=\"main\"\/> \n    <\/bean>\n\n    <bean class=\"example.SimpleMovieCatalog\">\n        <qualifier value=\"action\"\/> \n    <\/bean>\n\n    <bean id=\"movieRecommender\" class=\"example.MovieRecommender\"\/>\n\n<\/beans><\/code><\/pre>\n\n\n\n
\u9ed8\u8ba4\u4f7f\u7528bean\u7684\u540d\u79f0\u4f5c\u4e3a\u4f9d\u636e\uff0c\u5373<bean\/>\u5143\u7d20\u7684id\u5c5e\u6027\u3002
\u548c@Autowired\u4e00\u8d77\u7528\u7684\u65f6\u5019\u4f1a\u5728\u76f8\u540c\u7c7b\u578b\u7684\u5019\u9009\u4e2d<\/strong>\u9009id\u5339\u914d\u7684bean\u3002
\u597d\u7684qualifier\u540d\u79f0\u5e94\u8be5\u8868\u8fbebean\u7684\u7279\u70b9\uff0c\u5e76\u72ec\u7acb\u4e8eid\u3002
\u540c\u6837\u53ef\u4ee5\u5c06\u6240\u6709\u5339\u914d\u5230\u7684bean\u6ce8\u5165\u6210\u96c6\u5408\u3002<\/p>\n\n\n\n
\u8fd9\u5c31\u6697\u793aqualifiers\u5e76\u4e0d\u9700\u8981\u662f\u4e0d\u540c\u7684\uff0c\u4f8b\u5982\uff1a
\u5b9a\u4e49\u591a\u4e2aMovieCatalog\u7c7b\u578bbean\uff0c\u90fd\u542b\u6709\u76f8\u540c\u7684qualifier\u503c\uff1aaction\uff0c
\u90fd\u4f1a\u88ab\u6ce8\u5165\u7531@Qualifier(“action”)<\/strong>\u6ce8\u91ca\u7684Set<MovieCatalog>\u3002<\/p>\n\n\n\n
\u5728\u540c\u4e00\u7c7b\u578b\u5019\u9009\u8303\u56f4\u5185\u4f7f\u7528qualifier\u503c\u9009\u62e9\u800c\u4e0d\u662fbean\u540d\u79f0\uff0c\u53ef\u4ee5\u4e0d\u7528\u5728\u6ce8\u5165\u70b9\u6dfb\u52a0@Qualifier<\/strong>\u6ce8\u89e3\u3002
\u5728\u6ca1\u6709\u89e3\u6790\u6307\u793a\u7b26\u800c\u4e14\u6709\u591a\u4e2a\u5339\u914d\u7684\u60c5\u51b5\u4e0b\uff0cSpring\u4f1a\u9009\u62e9name\u548c\u6ce8\u5165\u70b9\u540d\u79f0\u76f8\u540c\u7684\u90a3\u4e2abean\u3002<\/p>\n\n\n\n
\u5982\u679c\u60f3\u5728\u6ce8\u89e3\u914d\u7f6e\u4e0b\u901a\u8fc7name\u81ea\u52a8\u6ce8\u5165\uff0c\u5c31\u4e0d\u5e94\u8be5\u4e3b\u7528@Autowired\uff0c\u867d\u7136\u5b83\u4e5f\u53ef\u4ee5\u3002
\u5e94\u8be5\u4f7f\u7528JSR-250\u00a0@Resource<\/strong><\/code>\u6ce8\u89e3\uff0c\u5728\u8bed\u4e49\u4e0a\u5c31\u88ab\u5b9a\u4e49\u6210\u901a\u8fc7\u7ec4\u4ef6\u7684\u540d\u79f0\u786e\u5b9a\u5339\u914d\u9879\uff0c\u548c\u7c7b\u578b\u65e0\u5173\u3002
@Autowired\u6709\u5b8c\u5168\u4e0d\u540c\u7684\u8bed\u4e49\uff1a\u5728\u901a\u8fc7\u7c7b\u578b\u9009\u62e9\u540e\uff0c\u5728\u8fd9\u4e9b\u5019\u9009\u91cc\u9762\u9009\u62e9qualifier\u503c\u5339\u914d\u7684\u90a3\u4e2a\u3002
\uff08\u7c7b\u578b\u6709\u5173\uff09<\/p>\n\n\n\n
\u5bf9\u4e8e\u7c7b\u578b\u662f\u96c6\u5408\u3001Map\u6216\u6570\u7ec4\u7684bean\u6765\u8bf4\uff0c@Resource<\/strong><\/code>\u662f\u4e00\u4e2a\u597d\u7684\u9009\u62e9\uff0c\u56e0\u4e3a\u662f\u901a\u8fc7\u540d\u79f0\u5339\u914d\u7684\u3002
\u4eceSpring4.3\u5f00\u59cb\uff0c@Autowired\u4e5f\u80fd\u6ce8\u5165\u96c6\u5408\uff0c\u53ea\u8981\u7c7b\u578b\u4fe1\u606f\u901a\u8fc7@Bean\u51fd\u6570\u7b7e\u540d\u6216\u96c6\u5408\u7ee7\u627f\u7ed3\u6784\u8fd4\u56de\u3002<\/p>\n\n\n\n
\u4eceSpring4.3\u5f00\u59cb\uff0c@Autowired\u4e5f\u8003\u8651\u81ea\u6ce8\u5165\uff08\u5f15\u7528\u5df2\u7ecf\u6ce8\u5165\u7684bean\uff09\u3002
\u5e38\u89c4\u7684\u4f9d\u8d56\u4e4b\u95f4\u6709\u4f18\u5148\u7ea7\uff0c\u81ea\u6ce8\u5165\u4e0d\u53c2\u52a0\u9009\u62e9\u8fc7\u7a0b\uff0c\u6240\u4ee5\u5c31\u4e0d\u4f1a\u662fprimary\u7684\u3002
\u76f8\u53cd\u5730\uff0c\u81ea\u6ce8\u5165\u603b\u662f\u6700\u4f4e\u4f18\u5148\u7ea7\u3002\u81ea\u6ce8\u5165\u4ec5\u4f5c\u4e3a\u6700\u540e\u624b\u6bb5\u4f7f\u7528\u3002<\/p>\n\n\n\n
\u5728@Configuration\u7c7b\u5185\u6ce8\u5165\u5728\u8fd9\u4e2a\u7c7b\u5185\u5b9a\u4e49\u7684@Bean\u65b9\u6cd5\u540c\u6837\u662f\u81ea\u5f15\u7528\u3002
\u5728\u65b9\u6cd5\u7b7e\u540d\u5185\u61d2\u60f0\u5f15\u7528\u6216\u8005\u5c06@Bean\u65b9\u6cd5\u5b9a\u4e49\u6210static\u90fd\u4f1a\u5bfc\u81f4\u548c@Configuration\u7c7b\u548c\u5176\u751f\u547d\u5468\u671f\u89e3\u8026\u3002
\u5982\u679c\u4e0d\u8fd9\u4e48\u505a\uff0c\u8fd9\u79cdbean\u4ec5\u5728fallback\u9636\u6bb5\u4f1a\u88ab\u8003\u8651\uff0c\u800c\u4e14\u4f1a\u5c06\u522b\u7684@Configuration\u7c7b\u4f5c\u4e3aprimary\u3002<\/p>\n\n\n\n
@Autowired\u53ef\u88ab\u7528\u4e8e\u53d8\u91cf\u3001\u6784\u9020\u5668\u548c\u591a\u4e2a\u53c2\u6570\u7684\u65b9\u6cd5\uff0c\u4f5c\u4e3a\u533a\u522b\uff0c
@Resource\u4ec5\u652f\u6301\u7528\u4e8e\u53d8\u91cf\u548c\u4e00\u4e2a\u53c2\u6570\u7684setter\u65b9\u6cd5\u3002
\u6240\u4ee5\u5bf9\u4e8e\u6784\u9020\u5668\u548c\u591a\u53c2\u6570\u65b9\u6cd5\u65f6\u6700\u597d\u4f7f\u7528qualifier\u3002<\/p>\n\n\n\n
\u7528Java\u6cdb\u578b\u4f5c\u4e3aQualifier<\/strong><\/p>\n\n\n\n
\u53ef\u4ee5\u6ce8\u5165\u6cdb\u578b\u63a5\u53e3\uff1a<\/p>\n\n\n\n
@Configuration\npublic class MyConfiguration {\n\n    @Bean\n    public StringStore stringStore() {\n        return new StringStore();\n    }\n\n    @Bean\n    public IntegerStore integerStore() {\n        return new IntegerStore();\n    }\n}<\/code><\/pre>\n\n\n\n
\u5047\u8bbeStringStore\u5b9e\u73b0\u4e86Store<String>\u63a5\u53e3\u3001IntegerStore\u5b9e\u73b0\u4e86Store<Integer>\u63a5\u53e3\uff1a<\/p>\n\n\n\n
@Autowired\nprivate Store<String> s1; \/\/ <String> qualifier\uff0c\u6ce8\u5165stringStore\n\n@Autowired\nprivate Store<Integer> s2; \/\/<Integer> qualifier\uff0c\u6ce8\u5165integerStore<\/code><\/pre>\n\n\n\n
\u540c\u6837\u652f\u6301\u96c6\u5408\u7c7b\u578b\uff1a<\/p>\n\n\n\n
@Autowired\nprivate List<Store<Integer>> s;\n\/\/ Store<String> beans\u4e0d\u4f1a\u88ab\u6ce8\u5165<\/code><\/pre>\n\n\n\n
@Resource<\/code>\u6ce8\u89e3\u6ce8\u5165<\/strong><\/p>\n\n\n\n
Spring\u540c\u6837\u652f\u6301JSR-250 @Resource<\/code> \u6ce8\u89e3\uff08javax.annotation.Resource\uff09\uff0c\u4f5c\u7528\u5728\u53d8\u91cf\u6216\u8005setter\u65b9\u6cd5\u3002<\/p>\n\n\n\n
@Resource\u63a5\u53d7\u4e00\u4e2aname\u5c5e\u6027\uff0cSpring\u9ed8\u8ba4\u5c06\u5176\u89e3\u6790\u6210\u8981\u88ab\u6ce8\u5165\u7684bean\u540d\u79f0\uff1a<\/p>\n\n\n\n
public class SimpleMovieLister {\n\n    private MovieFinder movieFinder;\n\n    @Resource(name=\"myMovieFinder\") \n    public void setMovieFinder(MovieFinder movieFinder) {\n        this.movieFinder = movieFinder;\n    }\n}<\/code><\/pre>\n\n\n\n
\u5982\u679c\u4e0d\u63d0\u4f9b\u90a3\u4e48\u5c5e\u6027\uff0c\u90a3\u5c31\u4f7f\u7528\u4ece\u53d8\u91cf\u540d\u6216\u8005setter\u65b9\u6cd5\u7684\u53c2\u6570\u540d<\/strong>\u83b7\u5f97\uff1a<\/p>\n\n\n\n
public class SimpleMovieLister {\n\n    private MovieFinder movieFinder;\n\n    @Resource\n    public void setMovieFinder(MovieFinder movieFinder) {\n        this.movieFinder = movieFinder;\n    }\n}<\/code><\/pre>\n\n\n\n
\u4e0a\u9762\u7684\u4f8b\u5b50\u4e2d@Resource\u4f1a\u5bfb\u627e\u540d\u4e3amovieFinder\u7684bean\u3002
\u540d\u5b57\u5fc5\u987b\u662fApplicationContext\u5185\u7684CommonAnnotationBeanPostProcessor\u77e5\u9053\u7684\u3002<\/p>\n\n\n\n
name\u5c5e\u6027\u53ef\u4ee5\u901a\u8fc7JNDI\u89e3\u6790\uff0c\u5982\u679c\u660e\u786e\u8bbe\u7f6eSimpleJndiBeanFactory<\/code>\u7684\u8bdd\u3002<\/p>\n\n\n\n
\u5728\u89e3\u6790\u67d0\u4e9b\u4f17\u6240\u5468\u77e5\u7684\u4f9d\u8d56\uff08BeanFactory<\/code>,\u00a0ApplicationContext<\/code>,\u00a0ResourceLoader<\/code>,\u00a0ApplicationEventPublisher<\/code>, and\u00a0MessageSource<\/code>\u63a5\u53e3\uff09\u7684\u65f6\u5019\uff0c\u5982\u679c\u6ca1\u6709\u63d0\u4f9b\u660e\u786e\u7684name\u5c5e\u6027\uff0c\u5c31\u4f1a\u6309\u7167\u7c7b\u578b\u5339\u914d\u3002<\/p>\n\n\n\n
\u4f7f\u7528<\/strong>@Value<\/strong><\/code>\u6ce8\u89e3<\/strong><\/p>\n\n\n\n
\u901a\u5e38\u7528\u4e8e\u6ce8\u5165\u5916\u90e8\u5c5e\u6027\uff1a<\/p>\n\n\n\n
@Component\npublic class MovieRecommender {\n\n    private final String catalog;\n\n    public MovieRecommender(@Value(\"${catalog.name}\") String catalog) {\n        this.catalog = catalog;\n    }\n}<\/code><\/pre>\n\n\n\n
\u901a\u8fc7@PropertySource<\/strong>\u6ce8\u89e3\u6307\u5b9a\u6570\u636e\u6e90\uff1a<\/p>\n\n\n\n
@Configuration\n@PropertySource(\"classpath:application.properties\")\npublic class AppConfig { }<\/code><\/pre>\n\n\n\n
\u7136\u540e\u65b0\u5efa\u6216\u8005\u7f16\u8f91application.properties\u6587\u4ef6\uff1a<\/p>\n\n\n\n
catalog.name=MovieCatalog<\/code><\/pre>\n\n\n\n
\u8fd0\u884c\u65f6\uff0c\u5c31\u4f1a\u5c06\u4e0a\u9762String catalog\u53d8\u91cf\u7684\u503c\u8bbe\u7f6e\u6210MovieCatalog\u3002<\/p>\n\n\n\n
${catalog.name}\u88ab\u79f0\u4f5c\u5360\u4f4d\u7b26\uff0c
\u5982\u679c\u65e0\u6cd5\u89e3\u6790\uff0c\u9ed8\u8ba4\u5c31\u4f1a\u5c06\u6574\u4e2a\u5360\u4f4d\u7b26\u6ce8\u5165\u5230\u53d8\u91cf\uff0c\u5982${catalog.name}\u3002<\/p>\n\n\n\n
\u53ef\u4ee5\u901a\u8fc7\u58f0\u660e\u4e00\u4e2aPropertySourcesPlaceholderConfigurer\u7c7b\u578bbean\uff0c\u6539\u6210\u4e25\u683c\u7684\u63a7\u5236\u7b56\u7565\uff0c\u65e0\u6cd5\u89e3\u6790\u5360\u4f4d\u7b26\u5c06\u4f1a\u5bfc\u81f4\u521d\u59cb\u5316\u5931\u8d25\u3002\uff08\u5728Spring Boot\u4e2d\u6210\u4e3a\u9ed8\u8ba4\u521d\u59cb\u5316\u7b56\u7565\uff09\uff1a<\/p>\n\n\n\n
@Configuration\npublic class AppConfig {\n\n     @Bean\n     public static<\/strong> PropertySourcesPlaceholderConfigurer propertyPlaceholderConfigurer() {\n           return new PropertySourcesPlaceholderConfigurer();\n     }\n}<\/code><\/pre>\n\n\n\n
\u6ce8\u610f\uff1a\u8fd9\u4e2abean\u65b9\u6cd5\u5fc5\u9700\u662fstatic\u7684\u3002<\/strong>
\u8fd9\u4e2abean\u540c\u6837\u63d0\u4f9bsetPlaceholderPrefix<\/strong><\/code>\uff0csetPlaceholderSuffix<\/strong><\/code>\uff0c\u6216setValueSeparator<\/strong><\/code>\u7b49\u65b9\u6cd5\u81ea\u5b9a\u4e49\u5360\u4f4d\u7b26\u3002<\/p>\n\n\n\n
Spring Boot\u4e2d\u7684PropertySourcesPlaceholderConfigurer<\/strong>\u9ed8\u8ba4\u4f1a\u4eceapplication.properties<\/strong>\u548capplication.yml<\/strong>\u6587\u4ef6\u8bfb\u53d6\u5c5e\u6027\u4fe1\u606f\u3002<\/p>\n\n\n\n
Spring\u5185\u7f6e\u7684converter\u5141\u8bb8\u81ea\u52a8\u8f6c\u6362\u7b80\u5355\u7c7b\u578b\uff1a\u5982\u8f6c\u6362\u6210Integer\u6216int\uff0c\u5c06\u591a\u4e2a\u7528\u9017\u53f7\u9694\u5f00\u7684\u503c\u8f6c\u6362\u6210String\u7c7b\u578b\u7684Array\u3002<\/p>\n\n\n\n
\u53ef\u4ee5\u4e3a\u5360\u4f4d\u7b26\u63d0\u4f9b\u4e00\u4e2a\u9ed8\u8ba4\u503c\uff1a<\/p>\n\n\n\n
@Component\npublic class MovieRecommender {\n\n    private final String catalog;\n\n    public MovieRecommender(@Value(\"${catalog.name:defaultCatalog}\") String catalog) {\n        this.catalog = catalog;\n    }\n}<\/code><\/pre>\n\n\n\n
\u5f53catalog.name\u65e0\u6cd5\u89e3\u6790\u65f6\u5c31\u5c06String catalog\u7684\u503c\u8bbe\u7f6e\u6210defaultCatalog\u3002<\/p>\n\n\n\n
Spring\u4f7f\u7528ConversionService\u7c7b\u578b\u7684BeanPostProcessor\u5c06\u5b57\u7b26\u4e32\u8f6c\u6362\u6210\u5bf9\u5e94\u53c2\u6570\u7684\u7c7b\u578b\u3002
\u53ef\u4ee5\u63d0\u4f9b\u81ea\u5b9a\u4e49\u7684ConversionService\u6765\u8f6c\u6362\u81ea\u5b9a\u4e49\u7c7b\u578b\uff1a<\/p>\n\n\n\n
@Configuration\npublic class AppConfig {\n\n    @Bean\n    public ConversionService conversionService() {\n        DefaultFormattingConversionService conversionService = new DefaultFormattingConversionService();\n        conversionService.addConverter(new MyCustomConverter());\n        return conversionService;\n    }\n}<\/code><\/pre>\n\n\n\n
\u5f53@Value\u542b\u6709SpEL\u65f6\uff0c\u5728\u8fd0\u884c\u65f6\u4f1a\u81ea\u52a8\u8ba1\u7b97\u7ed3\u679c\uff0c\u5e76\u6ce8\u5165\u7ed3\u679c\uff1a<\/p>\n\n\n\n
@Component\npublic class MovieRecommender {\n\n    private final String catalog;\n\n    public MovieRecommender(@Value(\"#{systemProperties['user.catalog'] + 'Catalog' }\") String catalog) {\n        this.catalog = catalog;\n    }\n}<\/code><\/pre>\n\n\n\n
@PostConstruct<\/strong><\/code>\u548c@PreDestroy<\/strong><\/code><\/p>\n\n\n\n
CommonAnnotationBeanPostProcessor\u540c\u6837\u53ef\u4ee5\u8bc6\u522bJSR-250\u751f\u547d\u5468\u671f\u6ce8\u89e3\uff1a
javax.annotation.PostConstruct<\/code>\u548cjavax.annotation.PreDestroy<\/code><\/p>\n\n\n\n
\u548c\u751f\u547d\u5468\u671f\u65b9\u6cd5\u4e00\u6837\uff0c\u53ea\u4e0d\u8fc7\u662f\u6ce8\u89e3\u5f62\u5f0f\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
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