feat(HierarchyUtil): 添加用于处理层级结构的通用工具

2025-07-21 15:09:48 +08:00 · 2023-05-03 19:50:25 +08:00
parent d25421bafd
commit 573d65d02b
3 changed files with 488 additions and 0 deletions
--- a/hutool-core/src/test/java/org/dromara/hutool/core/lang/hierarchy/HierarchyUtilTest.java
+++ b/hutool-core/src/test/java/org/dromara/hutool/core/lang/hierarchy/HierarchyUtilTest.java
@@ -0,0 +1,127 @@
+package org.dromara.hutool.core.lang.hierarchy;
+
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.LinkedHashMap;
+import java.util.LinkedHashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Objects;
+import java.util.Set;
+import java.util.function.Function;
+import java.util.stream.Collectors;
+
+/**
+ * test for {@link HierarchyUtil}
+ *
+ * @author huangchengxing
+ */
+class HierarchyUtilTest {
+
+	private Map<String, String> tree;
+
+	@BeforeEach
+	void init() {
+		tree = new LinkedHashMap<>();
+
+		// 根节点
+		tree.put("0", null);
+
+		// 第一层
+		tree.put("0-1", "0");
+		tree.put("0-2", "0");
+		tree.put("0-3", "0");
+
+		// 第三层
+		tree.put("0-1-1", "0-1");
+		tree.put("0-1-2", "0-1");
+		tree.put("0-1-3", "0-1");
+
+		tree.put("0-2-1", "0-2");
+		tree.put("0-2-2", "0-2");
+		tree.put("0-2-3", "0-2");
+
+		tree.put("0-3-1", "0-3");
+		tree.put("0-3-2", "0-3");
+		tree.put("0-3-3", "0-3");
+	}
+
+	@Test
+	void testTraverseByBreadthFirst() {
+		// 按广度优先遍历所有节点
+		Set<String> nodes = new LinkedHashSet<>();
+		HierarchyUtil.traverseByBreadthFirst("0", HierarchyIterator.scan(t -> {
+			nodes.add(t);
+			return tree.entrySet().stream()
+				.filter(e -> Objects.equals(t, e.getValue()))
+				.map(Map.Entry::getKey)
+				.collect(Collectors.toList());
+		}));
+		Assertions.assertEquals(13, nodes.size());
+		Assertions.assertEquals(
+			new LinkedHashSet<>(Arrays.asList("0", "0-1", "0-2", "0-3", "0-1-1", "0-1-2", "0-1-3", "0-2-1", "0-2-2", "0-2-3", "0-3-1", "0-3-2", "0-3-3")),
+			nodes
+		);
+
+		// 按广度优先寻找 0-2-3
+		String target = HierarchyUtil.traverseByBreadthFirst("0", HierarchyIterator.find(parentFinder(),
+			t -> Objects.equals(t, "0-2-3") ? t : null
+		));
+		Assertions.assertEquals("0-2-3", target);
+
+		// 按广度优先获取 0-2 的所有子节点
+		List<String> children = HierarchyUtil.traverseByBreadthFirst(
+			"0", HierarchyIterator.collect(parentFinder(),
+				t -> Objects.equals(tree.get(t), "0-2") ? t : null
+			)
+		);
+		Assertions.assertEquals(3, children.size());
+		Assertions.assertEquals(new ArrayList<>(Arrays.asList("0-2-1", "0-2-2", "0-2-3")), children);
+	}
+
+	@Test
+	void testTraverseByDepthFirst() {
+		// 按深度优先遍历所有节点
+		Set<String> nodes = new LinkedHashSet<>();
+		HierarchyUtil.traverseByDepthFirst("0", HierarchyIterator.scan(t -> {
+			nodes.add(t);
+			return tree.entrySet().stream()
+				.filter(e -> Objects.equals(t, e.getValue()))
+				.map(Map.Entry::getKey)
+				.collect(Collectors.toList());
+		}));
+		Assertions.assertEquals(13, nodes.size());
+		Assertions.assertEquals(
+			new LinkedHashSet<>(Arrays.asList("0", "0-1", "0-1-1", "0-1-2", "0-1-3", "0-2", "0-2-1", "0-2-2", "0-2-3", "0-3", "0-3-1", "0-3-2", "0-3-3")),
+			nodes
+		);
+
+		// 按深度优先寻找 0-2-3
+		String target = HierarchyUtil.traverseByDepthFirst("0", HierarchyIterator.find(parentFinder(),
+			t -> Objects.equals(t, "0-2-3") ? t : null
+		));
+		Assertions.assertEquals("0-2-3", target);
+
+		// 按深度优先获取 0-2 的所有子节点
+		List<String> children = HierarchyUtil.traverseByDepthFirst(
+			"0", HierarchyIterator.collect(parentFinder(),
+				t -> Objects.equals(tree.get(t), "0-2") ? t : null
+			)
+		);
+		Assertions.assertEquals(3, children.size());
+		Assertions.assertEquals(new ArrayList<>(Arrays.asList("0-2-1", "0-2-2", "0-2-3")), children);
+	}
+
+	private Function<String, Collection<String>> parentFinder() {
+		return t -> tree.entrySet()
+			.stream()
+			.filter(e -> Objects.equals(t, e.getValue()))
+			.map(Map.Entry::getKey)
+			.collect(Collectors.toList());
+	}
+}