import java.lang.reflect.Field;
import java.lang.reflect.Modifier;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.function.BiConsumer;
import java.util.function.Function;
import java.util.function.Supplier;
import java.util.stream.Collectors;
/**
- @program: myUtil
- @description: 工具类 - 树状构造生成
- @author: syf
- @create: 2021-06-15 10:38
*/
public class TreeModel<T> {
/** * 下级字段名称 */private Function<T, ?> superColumn;/** * 以后比对字段 */private Function<T, ?> column;/** * 列表接管字段名 */private BiConsumer<T, List<T>> children;/** * 数据列表 */private List<T> list;/** * 数据解除关联性应用的对象 */private Supplier<T> decoupling;/** * 私有化工具类 */private TreeModel() {}/** * 初始化载入树状工具类 * * @param list 须要整合的数据列表 * @param superColumn 下级字段(对象::字段get办法) * @param column 本级字段(对象::字段get办法) * @param children 上级数据存储字段(对象::字段set办法) * @return 树状工具类 */public static <R> TreeModel<R> load(List<R> list, Function<R, ?> superColumn, Function<R, ?> column, BiConsumer<R, List<R>> children) { TreeModel<R> treeModel = new TreeModel<>(); treeModel.setSuperColumn(superColumn) .setColumn(column) .setChildren(children) .setList(list); return treeModel;}/** * 获取树状数据（不解除原汇合中对象与树状汇合对象的关联） * * @param initValue 根数据 * @return 树状数据数据列表 */public List<T> getTree(Object initValue) { List<T> tree = treeAll(initValue); if (tree != null && tree.size() > 0) { return tree.stream().filter(ls -> initValue.equals(superColumn.apply(ls))).collect(Collectors.toList()); } return tree;}/** * 获取树状数据（解除原汇合中对象与树状汇合对象的关联） * * @param initValue 根数据 * @param decoupling 解除关联对象（对象::new） * @return 树状数据数据列表 */public List<T> getTree(Object initValue, Supplier<T> decoupling) { this.setDecoupling(decoupling); return tree(initValue);}/** * 获取树状数据 * * @param initValue 根数据 * @return 树状数据 */private List<T> treeAll(Object initValue) { if (list == null || list.size() < 1) { return list; } List<T> collect = list.stream().filter(f -> initValue.equals(superColumn.apply(f))).collect(Collectors.toList()); if (collect.size() < 1) { return null; } collect.forEach(c -> children.accept(c, treeAll(column.apply(c)))); return collect;}private List<T> tree(Object o) { List<T> childrenList = new ArrayList<>(); if(o == null){ return childrenList; } for (T entity : list) { if (o.equals(superColumn.apply(entity))) { T now = decoupling.get(); copy(entity, now); childrenList.add(now); } } for (T cs : childrenList) { children.accept(cs, tree(column.apply(cs))); } return childrenList;}/** * 将source中的属性赋值给target * @param source 数据起源类 * @param target 数据接管类 */private void copy(T source, T target) { if (source == null) { throw new NullPointerException("dataSource"); } if (target == null) { target = decoupling.get(); } Field[] sourceFields = source.getClass().getDeclaredFields(); Field[] targetFields =[期货](https://www.gendan5.com/p/2021-06-11/248014.html) target.getClass().getDeclaredFields(); Map<String, Object> sourceMap = new HashMap<>(sourceFields.length); try { for (Field field : sourceFields) { if (Modifier.isFinal(field.getModifiers())) { continue; } field.setAccessible(true); sourceMap.put(field.getName(), field.get(source)); } for (Field field : targetFields) { Object o = sourceMap.get(field.getName()); if (o == null) { continue; } field.setAccessible(true); field.set(target, o); } } catch (IllegalAccessException e) { e.printStackTrace(); }}private TreeModel<T> setSuperColumn(Function<T, ?> superColumn) { if (superColumn == null) { throw new NullPointerException("superColumn"); } this.superColumn = superColumn; return this;}private TreeModel<T> setColumn(Function<T, ?> column) { if (column == null) { throw new NullPointerException("column"); } this.column = column; return this;}private TreeModel<T> setChildren(BiConsumer<T, List<T>> children) { if (children == null) { throw new NullPointerException("children"); } this.children = children; return this;}private void setList(List<T> list) { if (list == null || list.size() < 1) { throw new NullPointerException("list"); } this.list = list;}private void setDecoupling(Supplier<T> decoupling) { if (decoupling == null) { throw new NullPointerException("decoupling"); } this.decoupling = decoupling;}}