分享几个写简洁java代码的小技巧

@Data
// 指定前缀
@ConfigurationProperties(prefix = "developer")
@Component
public class DeveloperProperty {
    private String name;
    private String website;
    private String qq;
    private String phoneNumber;
}

@RestController
@RequiredArgsConstructor
public class PropertyController {
 
    final DeveloperProperty developerProperty;
 
    @GetMapping("/property")
    public Object index() {
       return developerProperty.getName();
    }
}

//获取子目录列表
public List<CatalogueTreeNode> getChild(String pid) {
            if (V.isEmpty(pid)) {
            pid = BasicDic.TEMPORARY_DIRECTORY_ROOT;
        }
        CatalogueTreeNode node = treeNodeMap.get(pid);
 
        return Optional.ofNullable(node)
                .map(CatalogueTreeNode::getChild)
                .orElse(Collections.emptyList());
    }

public static void main(String[] args) {
    String strs = "";
    String[] arr = new String[]{"aa", "cc", "bb"}; // 转换前的字符串数组
    StringBuilder sb = new StringBuilder();
    for (String ele : arr) {
      if (sb.length() > 0) {
        sb.append(",");
      }
      sb.append(ele);
    }
    strs = sb.toString(); // 转换后的逗号分隔字符串
    System.out.println(strs);
}

public static void main(String[] args) {
    String[] arr = new String[]{"aa", "cc", "bb"}; // 转换前的字符串数组
    String strs = String.join(",", arr); // 转换后的逗号分隔字符串
    System.out.println(strs);
}