springboot 加载自定义yml文件（@PropertySource）

谁践踏了优雅 2023-02-24 15:28 19阅读 0赞

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### springboot 加载自定义yml文件（@PropertySource） ###

**默认不能加载yml文件，需要自定义实现PropertySourceFactory接口的类进行加载**

### \*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\* ###

**相关类与接口**

**@PropertySource**

@Target({ElementType.TYPE})
    @Retention(RetentionPolicy.RUNTIME)
    @Documented
    @Repeatable(PropertySources.class)
    public @interface PropertySource {
     
        String[] value();    //加载文件位置
     
        String name() default "";
        boolean ignoreResourceNotFound() default false;
        String encoding() default "";
     
        Class<? extends PropertySourceFactory> factory() default PropertySourceFactory.class;
                            //自定义factory，默认不能加载yml文件，可自定义factory
    }

**PropertySourceFactory**

public interface PropertySourceFactory {
        PropertySource<?> createPropertySource(@Nullable String var1, EncodedResource var2) throws IOException;
    }

**DefaultPropertySourceFactory**

public class DefaultPropertySourceFactory implements PropertySourceFactory {
        public DefaultPropertySourceFactory() {
        }
    
        public PropertySource<?> createPropertySource(@Nullable String name, EncodedResource resource) throws IOException {
            return name != null ? new ResourcePropertySource(name, resource) : new ResourcePropertySource(resource);
        }
    }

**ResourcePropertySource**

public class ResourcePropertySource extends PropertiesPropertySource {
        @Nullable
        private final String resourceName;
    
    
    *************
    构造函数
    
        public ResourcePropertySource(String name, EncodedResource resource) throws IOException {
        public ResourcePropertySource(EncodedResource resource) throws IOException {
        public ResourcePropertySource(String name, Resource resource) throws IOException {
        public ResourcePropertySource(Resource resource) throws IOException {
    
        public ResourcePropertySource(String name, String location, ClassLoader classLoader) throws IOException {
        public ResourcePropertySource(String location, ClassLoader classLoader) throws IOException {
        public ResourcePropertySource(String name, String location) throws IOException {
        public ResourcePropertySource(String location) throws IOException {
    
    
        private ResourcePropertySource(String name, @Nullable String resourceName, Map<String, Object> source) {
    
    
    *************
    普通方法
    
        public ResourcePropertySource withName(String name) {
        public ResourcePropertySource withResourceName() {
    
        private static String getNameForResource(Resource resource) {

**YamlPropertiesFactoryBean**

public class YamlPropertiesFactoryBean extends YamlProcessor implements FactoryBean<Properties>, InitializingBean {
    
    	private boolean singleton = true;
    
    	@Nullable
    	private Properties properties;
    
    	public void setSingleton(boolean singleton) {
    	public boolean isSingleton() {
    
    	public Properties getObject() {
    	public Class<?> getObjectType() {
    
    
    	public void afterPropertiesSet() {
    		if (isSingleton()) {
    			this.properties = createProperties();
    		}
    	}
    
    	protected Properties createProperties() {
    		Properties result = CollectionFactory.createStringAdaptingProperties();
    		process((properties, map) -> result.putAll(properties));
    		return result;
    	}
    
    }

**YamlProcessor**

public abstract class YamlProcessor {
    
    	private final Log logger = LogFactory.getLog(getClass());
    
    	private ResolutionMethod resolutionMethod = ResolutionMethod.OVERRIDE;
    	private Resource[] resources = new Resource[0];
    
    	private List<DocumentMatcher> documentMatchers = Collections.emptyList();
    	private boolean matchDefault = true;
    	private Set<String> supportedTypes = Collections.emptySet();
    
    
    	public void setDocumentMatchers(DocumentMatcher... matchers) {
    	public void setMatchDefault(boolean matchDefault) {
    	public void setResolutionMethod(ResolutionMethod resolutionMethod) {
    	public void setResources(Resource... resources) {
    	public void setSupportedTypes(Class<?>... supportedTypes) {
    
    
    	protected void process(MatchCallback callback) {
    	protected final Map<String, Object> getFlattenedMap(Map<String, Object> source) {
    	protected Yaml createYaml() {
    
    	private boolean process(MatchCallback callback, Yaml yaml, Resource resource) {
    	private boolean process(Map<String, Object> map, MatchCallback callback) {
    
    	private void handleProcessError(Resource resource, IOException ex) {
    	private Map<String, Object> asMap(Object object) {
    	private void buildFlattenedMap(Map<String, Object> result, Map<String, Object> source, @Nullable String path) {
    
    
    
    **************
    内部接口
    
    	public interface MatchCallback {
    		void process(Properties properties, Map<String, Object> map);
    	}
    
    
    	public interface DocumentMatcher {
    		MatchStatus matches(Properties properties);
    	}
    
    
    	public enum MatchStatus {
    		FOUND,
    		NOT_FOUND,
    		ABSTAIN;
    
    		public static MatchStatus getMostSpecific(MatchStatus a, MatchStatus b) {
    			return (a.ordinal() < b.ordinal() ? a : b);
    		}
    	}
    
    
    	public enum ResolutionMethod {
    		OVERRIDE,
    		OVERRIDE_AND_IGNORE,
    		FIRST_FOUND
    	}
    
    
    
    **************
    内部类
    
    	private class FilteringConstructor extends Constructor {
    
    		FilteringConstructor(LoaderOptions loaderOptions) {
    			super(loaderOptions);
    		}
    
    		@Override
    		protected Class<?> getClassForName(String name) throws ClassNotFoundException {
    			Assert.state(YamlProcessor.this.supportedTypes.contains(name),
    					() -> "Unsupported type encountered in YAML document: " + name);
    			return super.getClassForName(name);
    		}
    	}
    
    }

**FactoryBean**

public interface FactoryBean<T> {
    
    	String OBJECT_TYPE_ATTRIBUTE = "factoryBeanObjectType";
    
    	T getObject() throws Exception;
    	Class<?> getObjectType();
    
    	default boolean isSingleton() {
    		return true;
    	}
    
    }

### \*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\* ###

**示例**

**\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\***

**配置文件**

![20200709214514393.png][]

**person.yml**

person:
      name: 瓜田李下
      age: 20

**\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\***

**pojo 层**

**Person**

@Data
    @Component
    @ConfigurationProperties(prefix = "person")
    @PropertySource(value = {"classpath:properties/person.yml"},factory = YamlPropertySourceFactory.class)
    public class Person {
    
        private String name;
        private Integer age;
    }

**\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\***

**config 层**

**YamlPropertySourceFactory**

public class YamlPropertySourceFactory implements PropertySourceFactory {
    
        @Override
        public PropertySource<?> createPropertySource(String s, EncodedResource encodedResource) throws IOException {
            Properties properties=loadFromYaml(encodedResource);
            String name=(s!=null?s:encodedResource.getResource().getFilename());
    
            return new PropertiesPropertySource(name,properties);
        }
    
        private Properties loadFromYaml(EncodedResource resource){
            YamlPropertiesFactoryBean yamlPropertiesFactoryBean=new YamlPropertiesFactoryBean();
            yamlPropertiesFactoryBean.setResources(resource.getResource());
            yamlPropertiesFactoryBean.afterPropertiesSet();
    
            return yamlPropertiesFactoryBean.getObject();
        }
    }

**\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\***

**controller 层**

**HelloController**

@RestController
    public class HelloController {
    
        @Resource
        private Person person;
    
        @RequestMapping("/hello")
        public String hello(){
            System.out.println(person);
    
            return "success";
        }
    }

### \*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\* ###

**使用测试**

**localhost:8080/hello**

2020-07-09 21:48:40.006  INFO 16416 --- [nio-8080-exec-1] o.s.web.servlet.DispatcherServlet        : Initializing Servlet 'dispatcherServlet'
    2020-07-09 21:48:40.011  INFO 16416 --- [nio-8080-exec-1] o.s.web.servlet.DispatcherServlet        : Completed initialization in 5 ms
    Person(name=瓜田李下, age=20)

**此时，可以使用注解读取yml文件**

[20200709214514393.png]: /images/20230209/fe1cd40381e84a56b6792335c8839049.png