上传后台管理系统代码

novel-admin/src/main/java/com/java2nb/common/utils/BuildTree.java

@@ -0,0 +1,89 @@
+package com.java2nb.common.utils;
+
+import com.java2nb.common.domain.Tree;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+public class BuildTree {
+
+	public static <T> Tree<T> build(List<Tree<T>> nodes) {
+
+		if (nodes == null) {
+			return null;
+		}
+		List<Tree<T>> topNodes = new ArrayList<Tree<T>>();
+
+		for (Tree<T> children : nodes) {
+
+			String pid = children.getParentId();
+			if (pid == null || "0".equals(pid)) {
+				topNodes.add(children);
+
+				continue;
+			}
+
+			for (Tree<T> parent : nodes) {
+				String id = parent.getId();
+				if (id != null && id.equals(pid)) {
+					parent.getChildren().add(children);
+					children.setHasParent(true);
+					parent.setChildren(true);
+					continue;
+				}
+			}
+
+		}
+
+		Tree<T> root = new Tree<T>();
+		if (topNodes.size() == 1) {
+			root = topNodes.get(0);
+		} else {
+			root.setId("-1");
+			root.setParentId("");
+			root.setHasParent(false);
+			root.setChildren(true);
+			root.setChecked(true);
+			root.setChildren(topNodes);
+			root.setText("顶级节点");
+			Map<String, Object> state = new HashMap<>(16);
+			state.put("opened", true);
+			root.setState(state);
+		}
+
+		return root;
+	}
+
+	public static <T> List<Tree<T>> buildList(List<Tree<T>> nodes, String idParam) {
+		if (nodes == null) {
+			return null;
+		}
+		List<Tree<T>> topNodes = new ArrayList<Tree<T>>();
+
+		for (Tree<T> children : nodes) {
+
+			String pid = children.getParentId();
+			if (pid == null || idParam.equals(pid)) {
+				topNodes.add(children);
+
+				continue;
+			}
+
+			for (Tree<T> parent : nodes) {
+				String id = parent.getId();
+				if (id != null && id.equals(pid)) {
+					parent.getChildren().add(children);
+					children.setHasParent(true);
+					parent.setChildren(true);
+
+					continue;
+				}
+			}
+
+		}
+		return topNodes;
+	}
+
+}