通用TreeUtil

刺骨的言语ヽ痛彻心扉 2024-03-26 22:45 31阅读 0赞

## 通用TreeUtil ##

import lombok.extern.slf4j.Slf4j;
    import org.springframework.stereotype.Component;
    
    import java.lang.reflect.Field;
    import java.util.ArrayList;
    import java.util.LinkedHashMap;
    import java.util.List;
    import java.util.Map;
    
    /**
    * 转树形结构工具类
    *
    * @Description:
    */
    @Component
    @Slf4j
    public class TreeUtil<T> {
    
       public List<T> tree;
    
       /**
        * @param treeData 数据
        * @param rootId   根节点id
        * @return
        */
       public List<Object> treeMenu(List<T> treeData, String rootId) {
           this.tree = treeData;
           return child(rootId);
       }
    
       public List<Object> child(String id) {
           List<Object> lists = new ArrayList<Object>();
           for (T treeNode : tree) {
               Map<String, Object> childArray = new LinkedHashMap<String, Object>();
               try {
                   //获取父节点id
                   Field f = treeNode.getClass().getDeclaredField("pId");
                   f.setAccessible(true);
                   Object pId = f.get(treeNode);
    
                   if (pId.equals(id)) {
                       setTreeMap(childArray, treeNode);
                       lists.add(childArray);
                   }
               } catch (NoSuchFieldException | IllegalAccessException e) {
                   log.error(e.getMessage(), e);
               }
           }
           return lists;
       }
    
       private void setTreeMap(Map<String, Object> mapArr, T treeNode) {
           try {
               //获取所有属性字段，组装
               Field[] fs = treeNode.getClass().getDeclaredFields();
               for (Field f : fs) {
                   f.setAccessible(true);
                   String name = f.getName();
                   Object o = f.get(treeNode);
                   mapArr.put(name, o);
                   if ("children".equals(f.getName())) {
                       Field field = treeNode.getClass().getDeclaredField("id");
                       field.setAccessible(true);
                       Object obj = field.get(treeNode);
                       mapArr.put("children", child(String.valueOf(obj)));
                   }
               }
           } catch (NoSuchFieldException | IllegalAccessException e) {
               log.error(e.getMessage(), e);
           }
       }
    }

/**
    *实体类XXX至少包含id,pId,children三个属性字段
    */
     
    List<Object> treeData = treeUtil.treeMenu(roleArr.toJavaList(XXX.class),"0");