JAVA读取yml配置文件指定key下的所有内容

先引入需要的依赖

        <!--读取yml文件-->
        <dependency>
            <groupId>org.yaml</groupId>
            <artifactId>snakeyaml</artifactId>
            <version>1.23</version>
        </dependency>

读取YML文件工具类的代码

import org.apache.commons.lang3.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.util.ResourceUtils;
import org.yaml.snakeyaml.Yaml;

import java.io.*;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;

/**
 * @author hunmeng
 * @create 2020-01-10 20:34
 */
public class YmlUtils {

    private static final Logger LOGGER = LoggerFactory.getLogger(YmlUtils.class);

    private static String bootstrap_file = "classpath:application-test.yml";

    private static Map<String,String> result = new HashMap<>();

    /**
     * 根据文件名获取yml的文件内容
     * @param filePath
     * @param keys 第一个参数对应第一个key，第二个参数对应第二个key 比如spring.name下的所有 就是两个参数、
     *              getYmlByFileName(bootstrap_file,"spring", "name");
     * @return
     */
    public static Map<String,String> getYmlByFileName(String filePath, String... keys) {
        result = new HashMap<>();
        if(filePath == null) filePath = bootstrap_file;
        InputStream in = null;
        try {
            File file = ResourceUtils.getFile(filePath);
            in = new BufferedInputStream(new FileInputStream(file));
            Yaml props = new Yaml();
            Object obj = props.loadAs(in,Map.class);
            Map<String,Object> param = (Map<String, Object>) obj;

            for(Map.Entry<String,Object> entry:param.entrySet()){
                String key = entry.getKey();
                Object val = entry.getValue();
                if (keys.length != 0 && !keys[0].equals(key)){
                    continue;
                }
                if(val instanceof Map){
                    forEachYaml(key,(Map<String, Object>) val, 1, keys);
                }else{
                    result.put(key, val.toString());
                }
            }
            return result;
        } catch (FileNotFoundException e) {
            LOGGER.error(e.getMessage(),e);
        }finally {
            if (in != null){
                try {
                    in.close();
                } catch (IOException e) {
                    LOGGER.error(e.getMessage(),e);
                }
            }
        }
        return null;
    }

    /**
     * 根据key获取值
     * @param key
     * @return
     */
    public static String getValue(String key) throws FileNotFoundException {
        Map<String,String> map = getYmlByFileName(null);
        if(map==null)return null;
        return map.get(key);
    }

    /**
     * 遍历yml文件，获取map集合
     * @param key_str
     * @param obj
     * @param i
     * @param keys
     * @return
     */
    public static Map<String,String> forEachYaml(String key_str,Map<String, Object> obj, int i, String... keys){
        for(Map.Entry<String,Object> entry:obj.entrySet()){
            String key = entry.getKey();
            Object val = entry.getValue();
            if (keys.length > i && !keys[i].equals(key)){
                continue;
            }
            String str_new = "";
            if(StringUtils.isNotEmpty(key_str)){
                str_new = key_str+ "."+key;
            }else{
                str_new = key;
            }
            if(val instanceof Map){
                forEachYaml(str_new,(Map<String, Object>) val, ++i, keys);
                i--;
            }else{

                result.put(str_new,val.toString());
            }
        }

        return result;
    }

    /**
     * 获取bootstrap.yml的name
     * @return
     */
    public static String getApplicationName() throws FileNotFoundException {
        return getYmlByFileName(bootstrap_file).get("server.port");
    }

    /**
     * 获取bootstrap.yml的name
     * @return
     */
    public static String getApplicationName1() throws FileNotFoundException {
        String name =  getYmlByFileName(bootstrap_file).get("spring.application.name");
        return name + "center";
    }

    public static void main(String[] args) throws FileNotFoundException {

        Map<String, String> ymlByFileName = getYmlByFileName(bootstrap_file,"spring");
        Set<Map.Entry<String, String>> entries = ymlByFileName.entrySet();
        for (Map.Entry<String, String> entry : entries) {
            System.out.println(entry.getKey()+"==="+entry.getValue());
        }

        System.out.println(getApplicationName());
    }

}