允许构建时进行排序。

This commit is contained in:
zhouxy108 2024-04-16 21:06:02 +08:00
parent 22687605b2
commit d3b19c6cb0
2 changed files with 115 additions and 40 deletions

View File

@ -1,6 +1,7 @@
package xyz.zhouxy.plusone.commons.util;
import java.util.Collection;
import java.util.Comparator;
import java.util.List;
import java.util.Map;
import java.util.Optional;
@ -8,25 +9,88 @@ import java.util.function.BiConsumer;
import java.util.function.Function;
import java.util.stream.Collectors;
import javax.annotation.Nullable;
import com.google.common.base.Preconditions;
/**
* TreeBuilder
*
* @author <a href="http://zhouxy.xyz:3000/ZhouXY108">ZhouXY</a>
* @since 1.0
*/
public class TreeBuilder<T, TSubTree extends T, TIdentity> {
private final Function<T, TIdentity> identityGetter;
private final Function<T, Optional<TIdentity>> parentIdentityGetter;
private final BiConsumer<TSubTree, T> addChildMethod;
private final Comparator<? super T> defaultComparator;
public TreeBuilder(Function<T, TIdentity> identityGetter, Function<T, Optional<TIdentity>> parentIdentityGetter,
BiConsumer<TSubTree, T> addChild) {
this(identityGetter, parentIdentityGetter, addChild, null);
}
public TreeBuilder(Function<T, TIdentity> identityGetter, Function<T, Optional<TIdentity>> parentIdentityGetter,
BiConsumer<TSubTree, T> addChild, Comparator<? super T> defaultComparator) {
this.identityGetter = identityGetter;
this.parentIdentityGetter = parentIdentityGetter;
this.addChildMethod = addChild;
this.defaultComparator = defaultComparator;
}
/**
* 将节点构建成树使用 {@link #defaultComparator} 进行排序如果 {@link #defaultComparator}
* <p>
* <b>注意该方法会直接操作 nodes 列表中的节点并没有做深拷贝
* 注意避免 nodes 中的元素产生变化所带来的意料之外的影响</b>
*
* @param nodes 平铺的节点列表
*/
public List<T> buildTree(Collection<T> nodes) {
Map<TIdentity, T> identityNodeMap = nodes.stream()
Preconditions.checkNotNull(nodes);
return buildTreeInternal(nodes, this.defaultComparator);
}
/**
* 将节点构建成树
* <p>
* <b>注意该方法会直接操作 nodes 列表中的节点并没有做深拷贝
* 注意避免 nodes 中的元素产生变化所带来的意料之外的影响</b>
*
* @param nodes 平铺的节点列表
* @param comparator 用于节点的排序
* 若为 {@code null}则使用 {@link #defaultComparator}
* {@link #defaultComparator} 也为 {@code null}则不排序
*/
public List<T> buildTree(Collection<T> nodes, @Nullable Comparator<? super T> comparator) {
Preconditions.checkNotNull(nodes);
final Comparator<? super T> c = (comparator != null) ? comparator : this.defaultComparator;
return buildTreeInternal(nodes, c);
}
/**
* 将节点构建成树
* <p>
* <b>注意该方法会直接操作 nodes 列表中的节点并没有做深拷贝
* 注意避免 nodes 中的元素产生变化所带来的意料之外的影响</b>
*
* @param nodes 平铺的节点列表
* @param comparator 用于节点的排序若为 {@code null}则不排序
*/
private List<T> buildTreeInternal(Collection<T> nodes, @Nullable Comparator<? super T> comparator) {
final Collection<T> allNodes;
if (comparator == null) {
allNodes = nodes;
} else {
allNodes = nodes.stream().sorted(comparator).collect(Collectors.toList());
}
final Map<TIdentity, T> identityNodeMap = allNodes.stream()
.collect(Collectors.toMap(identityGetter, Function.identity(), (n1, n2) -> n1));
List<T> result = nodes.stream()
final List<T> result = allNodes.stream()
.filter(node -> !this.parentIdentityGetter.apply(node).isPresent())
.collect(Collectors.toList());
nodes.forEach(node -> parentIdentityGetter.apply(node).ifPresent(parentIdentity -> {
allNodes.forEach(node -> parentIdentityGetter.apply(node).ifPresent(parentIdentity -> {
if (identityNodeMap.containsKey(parentIdentity)) {
@SuppressWarnings("unchecked")
TSubTree parentNode = (TSubTree) identityNodeMap.get(parentIdentity);

View File

@ -17,29 +17,34 @@ class TreeBuilderTests {
private static final Logger log = LoggerFactory.getLogger(TreeBuilderTests.class);
private final TreeBuilder<Menu, MenuList, String> treeBuilder = new TreeBuilder<>(
Menu::getMenuCode,
Menu::getParentMenuCode,
MenuList::addChild);
menu -> Optional.ofNullable(menu.parentMenuCode),
MenuList::addChild,
(a, b) -> Integer.compare(a.getOrderNum(), b.getOrderNum()));
@Test
void testBuildTree() {
List<Menu> menus = Lists.newArrayList(
MenuItem.of("A", "首页", "/home"),
MenuList.of("B", "系统管理"),
MenuItem.of("B", "B001", "功能管理", "/sys/function-mgmt"),
MenuItem.of("B", "B002", "角色管理", "/sys/role-mgmt"),
MenuItem.of("B", "B003", "账号管理", "/sys/account-mgmt"),
MenuItem.of("B", "B004", "系统参数管理", "/sys/param-mgmt"),
MenuList.of("C", "一级菜单C"),
MenuList.of("C", "C1", "二级菜单C1"),
MenuItem.of("C1", "C1001", "三级菜单C1001", "/c/c1/c1001"),
MenuItem.of("C1", "C1002", "三级菜单C1002", "/c/c1/c1002"),
MenuItem.of("C", "C2", "二级菜单C2", "/c/c2"),
MenuItem.of("C", "C3", "二级菜单C3", "/c/c3")
MenuList.of("B", "系统管理", 3),
MenuItem.of("A", "首页", "/home", 1),
/**/MenuItem.of("B", "B002", "角色管理", "/sys/role-mgmt", 3),
/**/MenuItem.of("B", "B001", "功能管理", "/sys/function-mgmt", 4),
/**/MenuItem.of("B", "B004", "系统参数管理", "/sys/param-mgmt", 1),
/**/MenuItem.of("B", "B003", "账号管理", "/sys/account-mgmt", 2),
MenuList.of("C", "一级菜单C", 2),
/**/MenuItem.of("C", "C3", "二级菜单C3", "/c/c3", 2),
/**/MenuList.of("C", "C1", "二级菜单C1", 2),
/**//**/MenuItem.of("C1", "C1001", "三级菜单C1001", "/c/c1/c1001", 1),
/**//**/MenuItem.of("C1", "C1002", "三级菜单C1002", "/c/c1/c1002", 2),
/**/MenuItem.of("C", "C2", "二级菜单C2", "/c/c2", 1));
List<Menu> menuTreeSortedByOrderNum = treeBuilder.buildTree(menus);
log.info("menuTreeSortedByOrderNum: {}", new Gson().toJson(menuTreeSortedByOrderNum));
List<Menu> menuTreeSortedByMenuCode = treeBuilder.buildTree(
menus,
(a, b) -> a.getMenuCode().compareTo(b.getMenuCode())
);
List<Menu> menuTree = treeBuilder.buildTree(menus);
log.info("menuTree: {}", new Gson().toJson(menuTree));
log.info("menuTreeSortedByMenuCode: {}", new Gson().toJson(menuTreeSortedByMenuCode));
}
}
@ -48,24 +53,30 @@ abstract class Menu {
protected final String parentMenuCode;
protected final String menuCode;
protected final String title;
protected final int orderNum;
public Menu(String parentMenuCode, String menuCode, String title) {
public Menu(String parentMenuCode, String menuCode, String title, int orderNum) {
this.parentMenuCode = parentMenuCode;
this.menuCode = menuCode;
this.title = title;
this.orderNum = orderNum;
}
public String getMenuCode() {
return menuCode;
}
public Optional<String> getParentMenuCode() {
return Optional.ofNullable(parentMenuCode);
public String getParentMenuCode() {
return parentMenuCode;
}
public String getTitle() {
return title;
}
public int getOrderNum() {
return orderNum;
}
}
@ToString(callSuper = true)
@ -73,17 +84,17 @@ class MenuItem extends Menu {
private final String url;
private MenuItem(String parentMenuCode, String menuCode, String title, String url) {
super(parentMenuCode, menuCode, title);
private MenuItem(String parentMenuCode, String menuCode, String title, String url, int orderNum) {
super(parentMenuCode, menuCode, title, orderNum);
this.url = url;
}
static MenuItem of(String parentMenuCode, String menuCode, String title, String url) {
return new MenuItem(parentMenuCode, menuCode, title, url);
static MenuItem of(String parentMenuCode, String menuCode, String title, String url, int orderNum) {
return new MenuItem(parentMenuCode, menuCode, title, url, orderNum);
}
static MenuItem of(String menuCode, String title, String url) {
return new MenuItem(null, menuCode, title, url);
static MenuItem of(String menuCode, String title, String url, int orderNum) {
return new MenuItem(null, menuCode, title, url, orderNum);
}
public String getUrl() {
@ -96,24 +107,24 @@ class MenuList extends Menu {
private List<Menu> children;
private MenuList(String parentMenuCode, String menuCode, String title) {
super(parentMenuCode, menuCode, title);
private MenuList(String parentMenuCode, String menuCode, String title, int orderNum) {
super(parentMenuCode, menuCode, title, orderNum);
}
static MenuList of(String parentMenuCode, String menuCode, String title) {
return new MenuList(parentMenuCode, menuCode, title);
static MenuList of(String parentMenuCode, String menuCode, String title, int orderNum) {
return new MenuList(parentMenuCode, menuCode, title, orderNum);
}
static MenuList of(String menuCode, String title) {
return new MenuList(null, menuCode, title);
static MenuList of(String menuCode, String title, int orderNum) {
return new MenuList(null, menuCode, title, orderNum);
}
static MenuList of(String menuCode, String title, Iterable<Menu> children) {
return of(null, menuCode, title, children);
static MenuList of(String menuCode, String title, Iterable<Menu> children, int orderNum) {
return of(null, menuCode, title, children, orderNum);
}
static MenuList of(String parentMenuCode, String menuCode, String title, Iterable<Menu> children) {
MenuList instance = of(parentMenuCode, menuCode, title);
static MenuList of(String parentMenuCode, String menuCode, String title, Iterable<Menu> children, int orderNum) {
MenuList instance = of(parentMenuCode, menuCode, title, orderNum);
for (Menu child : children) {
instance.addChild(child);
}