{"id":8365,"date":"2022-11-09T12:21:12","date_gmt":"2022-11-09T04:21:12","guid":{"rendered":"http:\/\/123.57.164.21\/?p=8365"},"modified":"2022-11-09T12:21:12","modified_gmt":"2022-11-09T04:21:12","slug":"spring%e4%b8%adlazy%e6%b3%a8%e8%a7%a3%e7%9a%84%e4%bd%bf%e7%94%a8","status":"publish","type":"post","link":"https:\/\/92it.top\/?p=8365","title":{"rendered":"Spring\u4e2d@Lazy\u6ce8\u89e3\u7684\u4f7f\u7528"},"content":{"rendered":"\n<pre class=\"wp-block-preformatted\">Spring\u5728\u5e94\u7528\u7a0b\u5e8f\u4e0a\u4e0b\u6587\u542f\u52a8\u65f6\u53bb\u521b\u5efa\u6240\u6709\u7684\u5355\u4f8bbean\u5bf9\u8c61, \u800c@Lazy\u6ce8\u89e3\u53ef\u4ee5\u5ef6\u8fdf\u52a0\u8f7dbean\u5bf9\u8c61,\u5373\u5728\u4f7f\u7528\u65f6\u624d\u53bb\u521d\u59cb\u5316. \u6240\u4ee5@Lazy\u6ce8\u89e3, \u4e00\u662f\u53ef\u4ee5\u51cf\u5c11Spring\u7684IOC\u5bb9\u5668\u542f\u52a8\u65f6\u7684\u52a0\u8f7d\u65f6\u95f4, \u4e8c\u662f\u53ef\u4ee5\u89e3\u51b3bean\u7684\u5faa\u73af\u4f9d\u8d56\u95ee\u9898\n<\/pre>\n\n\n\n<p><strong>1 .@Lazy\u7684\u7b80\u4ecb<\/strong><\/p>\n\n\n\n<hr class=\"wp-block-separator\"\/>\n\n\n\n<p>@Lazy\u6ce8\u89e3\u7528\u4e8e\u6807\u8bc6bean\u662f\u5426\u9700\u8981\u5ef6\u8fdf\u52a0\u8f7d.<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">@Target({ElementType.TYPE, ElementType.METHOD, ElementType.CONSTRUCTOR, ElementType.PARAMETER, ElementType.FIELD})\n@Retention(RetentionPolicy.RUNTIME)\n@Documented\npublic @interface Lazy {\n\n\t\/**\n\t * Whether lazy initialization should occur.\n\t *\/\n\tboolean value() default true;\n\n}<\/pre>\n\n\n\n<p>\u67e5\u770b\u6ce8\u89e3\u6e90\u7801\u53ef\u77e5,\u53ea\u6709\u4e00\u4e2a\u53c2\u6570, \u9ed8\u8ba4\u4e3atrue, \u5373\u6dfb\u52a0\u8be5\u6ce8\u89e3\u7684bean\u5bf9\u8c61\u5c31\u4f1a\u5ef6\u8fdf\u521d\u59cb\u5316.<\/p>\n\n\n\n<p><strong>2.@Lazy\u7684\u4f7f\u7528<\/strong><\/p>\n\n\n\n<hr class=\"wp-block-separator\"\/>\n\n\n\n<p>\u4ee5SpringBoot\u73af\u5883\u4e3a\u4f8b<\/p>\n\n\n\n<p>1 \u51c6\u5907\u4e00\u4e2aSpringboot\u73af\u5883<\/p>\n\n\n\n<p>2 \u51c6\u5907\u4e24\u4e2a\u5b9e\u4f53\u7c7b\u5bf9\u8c61<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">@Data\n@NoArgsConstructor\npublic class User {\n\n    private String name;\n    private String phone;\n    private Integer age;\n    private Person person;\n\n    public User(String name, String phone, Integer age) {\n        System.out.println(\"\u6211User\u88ab\u521d\u59cb\u5316\u4e86.............\");\n        this.name = name;\n        this.phone = phone;\n        this.age = age;\n    }\n}\n<\/pre>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">@Data\n@NoArgsConstructor\npublic class Person {\n\n    private String name;\n    private String phone;\n    private Integer age;\n    private User user;\n\n    public Person(String name, String phone, Integer age) {\n        System.out.println(\"\u6211Person\u88ab\u521d\u59cb\u5316\u4e86.............\");\n        this.name = name;\n        this.phone = phone;\n        this.age = age;\n    }\n}\n<\/pre>\n\n\n\n<p>3 \u6dfb\u52a0\u542f\u52a8\u7c7b<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">@SpringBootApplication\npublic class Application {\n\n    public static void main(String[] args) {\n        SpringApplication.run(Application.class, args);\n    }\n\n    @Bean\n    public User createUser() {\n        return new User(\"\u97e9\u5ba3\u751f\", \"11111\", 24);\n    }\n\n    @Bean\n    @Lazy\n    public Person createPerson() {\n        return new Person(\"\u97e9\u7acb\", \"11111\", 24);\n    }\n}<\/pre>\n\n\n\n<p>4 \u6d4b\u8bd5\u67e5\u770b\u63a7\u5236\u53f0<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\">\u6211User\u88ab\u521d\u59cb\u5316\u4e86.............<\/pre>\n\n\n\n<p>5 \u53bb\u6389Person\u4e0a\u7684 @Lazy\u6ce8\u89e3,\u91cd\u542f\u9879\u76ee<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\">\u6211User\u88ab\u521d\u59cb\u5316\u4e86.............\n\u6211Person\u88ab\u521d\u59cb\u5316\u4e86.............<\/pre>\n\n\n\n<p><strong>3 @Lazy\u7684\u4f5c\u7528<\/strong><\/p>\n\n\n\n<hr class=\"wp-block-separator\"\/>\n\n\n\n<ul><li>1 \u5ef6\u8fdf\u52a0\u8f7dbean\u5bf9\u8c61(\u5982\u4e0a\u6848\u5217)<\/li><\/ul>\n\n\n\n<ul><li>2 \u89e3\u51b3\u5faa\u73af\u4f9d\u8d56\u95ee\u9898<\/li><\/ul>\n\n\n\n<p>1 \u6dfb\u52a0\u4e24\u4e2a\u914d\u7f6e\u7c7b<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">@Component\npublic class PersonConfig {\n\n    private UserConfig userConfig;\n\n    public PersonConfig( UserConfig userConfig) {\n        this.userConfig = userConfig;\n        System.out.println(\"\u6211\u662f\u7528\u6237\u914d\u7f6e PersonConfig\");\n    }\n\n}\n<\/pre>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">@Component\npublic class UserConfig {\n\n    private PersonConfig personConfig;\n\n    public UserConfig(PersonConfig personConfig) {\n        this.personConfig = personConfig;\n        System.out.println(\"\u6211\u662f\u7528\u6237\u914d\u7f6e UserConfig\");\n    }\n}\n<\/pre>\n\n\n\n<p>2 \u91cd\u542f\u9879\u76ee, \u9879\u76ee\u62a5\u9519,\u4ee3\u7801\u4e2d\u5b58\u5728\u5faa\u73af\u4f9d\u8d56<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">Description:\n\nThe dependencies of some of the beans in the application context form a cycle:<\/pre>\n\n\n\n<p>\u89e3\u51b3\u529e\u6cd5,\u7ed9\u5176\u4e2d\u4e00\u4e2a\u6dfb\u52a0@Lazy\u6ce8\u89e3,\u5982<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">@Component\npublic class PersonConfig {\n\n    private UserConfig userConfig;\n\n\n    public PersonConfig(@Lazy UserConfig userConfig) {\n        this.userConfig = userConfig;\n        System.out.println(\"\u6211\u662f\u7528\u6237\u914d\u7f6e PersonConfig\");\n    }\n\n}\n<\/pre>\n\n\n\n<p>3 \u91cd\u542f\u9879\u76ee,\u67e5\u770b\u65e5\u5fd7<\/p>\n\n\n\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">\u6211\u662f\u7528\u6237\u914d\u7f6e PersonConfig\n\u6211\u662f\u7528\u6237\u914d\u7f6e UserConfig<\/pre>\n","protected":false},"excerpt":{"rendered":"<p>Spring\u5728\u5e94\u7528\u7a0b\u5e8f\u4e0a\u4e0b\u6587\u542f\u52a8\u65f6\u53bb\u521b\u5efa\u6240\u6709\u7684\u5355\u4f8bbean\u5bf9\u8c61, \u800c@Lazy\u6ce8\u89e3\u53ef\u4ee5\u5ef6\u8fdf\u52a0\u8f7dbean\u5bf9\u8c61,\u5373 [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[26,27],"tags":[],"_links":{"self":[{"href":"https:\/\/92it.top\/index.php?rest_route=\/wp\/v2\/posts\/8365"}],"collection":[{"href":"https:\/\/92it.top\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/92it.top\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/92it.top\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/92it.top\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=8365"}],"version-history":[{"count":4,"href":"https:\/\/92it.top\/index.php?rest_route=\/wp\/v2\/posts\/8365\/revisions"}],"predecessor-version":[{"id":8369,"href":"https:\/\/92it.top\/index.php?rest_route=\/wp\/v2\/posts\/8365\/revisions\/8369"}],"wp:attachment":[{"href":"https:\/\/92it.top\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=8365"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/92it.top\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=8365"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/92it.top\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=8365"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}