Java 构建不限级别,不限字段个数的树形菜单

我们要用到树形菜单的时候需要一些工具类,但是菜单显示的内容或者字段个数不一样,要统一封装,直接上代码

package common;

import org.apache.commons.lang.StringUtils;

import java.util.ArrayList;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;


/**
 *  * 类名称：MenuTreeUtil
 *  * 类描述：递归构造树型结构
 *  
 */
public class MenuTreeUtil {
    public static Map<String, Object> mapArray = new LinkedHashMap<String, Object>();
    public List<Map<String,Object>> menuCommon;
    public List<Object> list = new ArrayList<Object>();

    /***
     *
     * @param menuList
     * @param ids 主键 {"显示的字段","数据库查询出来的字段"}
     * @param parentIds 父键{"显示的字段","数据库查询出来的字段"}
     * @param names 名称{"显示的字段","数据库查询出来的字段"}
     * @param children 子集 key 例如: sub
     * @param params 其它参数列表 {"显示的字段","数据库查询出来的字段"}
     * @return
     */
    public  List<Object> menuList(List<Map<String,Object>> menuList,String[] ids,String[] parentIds,String[] names,String children,String[]... params) {
        if(menuList ==null){
            menuList=new ArrayList<Map<String,Object>>();
        }
        this.menuCommon = menuList;
        for (Map<String,Object> x : menuList) {
            Map<String, Object> mapArr = new LinkedHashMap<String, Object>();
            String s=x.get(parentIds[1]).toString();
            System.out.println("_________________________________________________________________________________"+s);
            if ("0".equals(s)) {
                mapArr.put(ids[0], x.get(ids[1]));
                mapArr.put(parentIds[0], x.get(parentIds[1]));
                mapArr.put(names[0], x.get(names[1]));
                if(null != params){
                    for (int i=0;i<params.length;i++){
                        String [] tempArray=params[i];
                        mapArr.put(tempArray[0],x.get(tempArray[1]));
                    }
                }
                mapArr.put(children, menuChild(obj2Str(x.get(ids[1])),ids,parentIds,names,children,params));
                list.add(mapArr);
            }
        }
        return list;
    }

    /***
     *
     * @param id
     * @param ids
     * @param parentIds
     * @param names
     * @param children
     * @param params
     * @return
     */
    private List<?> menuChild(String id,String[] ids,String[] parentIds,String[] names,String children,String[]... params) {
        List<Object> lists = new ArrayList<Object>();
        for (Map<String,Object> a : menuCommon) {
            Map<String, Object> childArray = new LinkedHashMap<String, Object>();
            if (id.equals(obj2Str(a.get(parentIds[1])))) {
                childArray.put(ids[0], a.get(ids[1]));
                childArray.put(parentIds[0], a.get(parentIds[1]));
                childArray.put(names[0],a.get(names[1]));
                if(null != params){
                    for (int i=0;i<params.length;i++){
                        String [] tempArray=params[i];
                        childArray.put(tempArray[0],a.get(tempArray[1]));
                    }
                }
                childArray.put(children, menuChild(obj2Str(a.get(ids[1])),ids,parentIds,names,children,params));
                lists.add(childArray);
            }
        }
        return lists;
    }

    private static String  obj2Str(Object obj) {
        if(obj == null ){
            return "";
        }else{
            return obj.toString();
        }
    }

}

 

来源：CSDN

作者：代号793

链接：https://blog.csdn.net/u011267841/article/details/104795180