如何基于JAVA读取yml配置文件指定key内容

    
      org.yaml
      snakeyaml
      1.23
    

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 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 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 param = (Map) obj;

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

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