Maven Dependency

<dependency>
  <groupId>org.yaml</groupId>
  <artifactId>snakeyaml</artifactId>
  <version>1.14</version>
</dependency>

String → Map

Data

data1: AAA
data2:
  - aaa
  - bbb
  - ccc
data3:
  zzz: ZZZ
  yyy: YYY
  xxx: XXX

Code

        Yaml sYaml = new Yaml();
        @SuppressWarnings("unchecked")
        Map<String, Object> yaml = (Map<String, Object>) sYaml.load(yamlString);
        
        assertThat((String) yaml.get("data1"), is("AAA"));
        
        @SuppressWarnings("unchecked")
        List<String> data2 = (List<String>) yaml.get("data2");
        assertThat(data2.get(0), is("aaa"));
        assertThat(data2.get(1), is("bbb"));
        assertThat(data2.get(2), is("ccc"));
        
        @SuppressWarnings("unchecked")
        Map<String, String> data3 = (Map<String, String>) yaml.get("data3");
        assertThat(data3.get("zzz"), is("ZZZ"));
        assertThat(data3.get("yyy"), is("YYY"));
        assertThat(data3.get("xxx"), is("XXX"));

String → Bean

Data

!!com.YamlBean
data1: AAA
data2:
  - aaa
  - bbb
  - ccc
data3:
  zzz: ZZZ
  yyy: YYY
  xxx: XXX

Bean

YamlBean.java

package com;

import java.util.List;
import java.util.Map;

public class YamlBean {

    private String data1;
    private List<String> data2;
    private Map<String, String> data3;

    public String getData1() {
        return data1;
    }

    public void setData1(String data1) {
        this.data1 = data1;
    }

    public List<String> getData2() {
        return data2;
    }

    public void setData2(List<String> data2) {
        this.data2 = data2;
    }

    public Map<String, String> getData3() {
        return data3;
    }

    public void setData3(Map<String, String> data3) {
        this.data3 = data3;
    }
}

Code1

        Yaml yaml = new Yaml();
        YamlBean yamlBean = (YamlBean) yaml.load(yamlString);
        
        assertThat(yamlBean.getData1(), is("AAA"));
        assertThat(yamlBean.getData2().get(0), is("aaa"));
        assertThat(yamlBean.getData2().get(1), is("bbb"));
        assertThat(yamlBean.getData2().get(2), is("ccc"));
        assertThat(yamlBean.getData3().get("zzz"), is("ZZZ"));
        assertThat(yamlBean.getData3().get("yyy"), is("YYY"));
        assertThat(yamlBean.getData3().get("xxx"), is("XXX"));

Code2

こちらの書き方でも動作すると思っているのですが、
loadAsメソッドでNoSuchMethodErrorが発生しているので未確認。。。

        Yaml yaml = new Yaml();
        YamlBean yamlBean = yaml.loadAs(yamlString, YamlBean.class);
        
        assertThat(yamlBean.getData1(), is("AAA"));
        assertThat(yamlBean.getData2().get(0), is("aaa"));
        assertThat(yamlBean.getData2().get(1), is("bbb"));
        assertThat(yamlBean.getData2().get(2), is("ccc"));
        assertThat(yamlBean.getData3().get("zzz"), is("ZZZ"));
        assertThat(yamlBean.getData3().get("yyy"), is("YYY"));
        assertThat(yamlBean.getData3().get("xxx"), is("XXX"));