我想将列表中的所有字符串值保存到数据库中作为一个字符串。如果按照下面的实现，它会保存空值。是否有任何方法可以保存方法的返回值，而不是字段本身？
@Entity
@Table(name = "commands")
public class Command {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
@Column(name = "command")
private String command;
@Transient
private List<String> validResultList = new ArrayList<>();
public List<String> getValidResultList() {
    return validResultList;
}
public void setValidResultList(List<String> validResultList) {
    this.validResultList = validResultList;
}
@Column(name = "valid_commands")
public String getValidResultListAsString() {
    StringBuilder sb = new StringBuilder();
    for (String value : validResultList) {
        sb.append(value).append(" ");
    }
    return sb.toString();
}
}
字段 "valid_commands" 是 VARCHAR2。
例如：
Command comm1 = new Command("echo test;");
comm1.setValidResultList(Arrays.asList("foo", "bar"));
应该保存为：
"foo bar "