java 构建树
java 构建树
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概述
数据库中存储的树形结构的记录，根据条件查询出符合条件的节点及其父节点。
查询出来的数据构建树，并对其做排序和变量。
查询sql
SELECT distinct dm AS code, dm AS sortNo, fdm AS parentCode, mc AS codeName from cfg_az where ajlb = 2 start with dm in ('90','4192','4148', '4162', '4232','103', '4166')
connect by prior fdm=dm;构建树
@Data
public class HorzDmDto {
/**
* code
*/
private String code;
/**
* code 名称
*/
private String codeName;
/**
* 父节点
*/
private String parentCode;
/**
* 排序
*/
private String sortNo;
/**
* 层级
*/
private Integer level;
}public class HorzDmNode {
/**
* code
*/
private String code;
/**
* 根节点code
*/
private String rootCode;
/**
* code 名称
*/
private String codeName;
/**
* 父节点
*/
private HorzDmNode parentNode;
/**
* 子节点
*/
private List childrenNodes;
/**
* 排序号
*/
private Integer sortNo;
/**
* 层级: 根为0, 第一层子节点
*/
private Integer lever;
/**
* 最大层级
*/
private Integer maxLever = 0;
/**
* 存放所有父code
*/
private List parentCodePath = new ArrayList<>();
/**
* 存放所有父codeName
*/
private List parentCodeNamePath = new ArrayList<>();
/**
* 添加child
*
* @param childNode 子节点
*/
public void addChild(HorzDmNode childNode) {
if (childrenNodes == null) {
childrenNodes = new ArrayList<>();
}
childrenNodes.add(childNode);
}
public boolean isEndNode() {
if (childrenNodes == null || childrenNodes.isEmpty()) {
return true;
}
return false;
}
public String getCode() {
return code;
}
public void setCode(String code) {
this.code = code;
}
public String getCodeName() {
return codeName;
}
public void setCodeName(String codeName) {
this.codeName = codeName;
}
public HorzDmNode getParentNode() {
return parentNode;
}
public void setParentNode(HorzDmNode parentNode) {
this.parentNode = parentNode;
}
public List getChildrenNodes() {
return childrenNodes;
}
public void setChildrenNodes(List childrenNodes) {
this.childrenNodes = childrenNodes;
}
public Integer getSortNo() {
return sortNo;
}
public void setSortNo(Integer sortNo) {
this.sortNo = sortNo;
}
public Integer getLever() {
return lever;
}
public void setLever(Integer lever) {
this.lever = lever;
}
public Integer getMaxLever() {
return maxLever;
}
public void setMaxLever(Integer maxLever) {
if (maxLever > this.maxLever) {
this.maxLever = maxLever;
}
}
public List getParentCodePath() {
return parentCodePath;
}
public void setParentCodePath(List parentCodePath) {
this.parentCodePath = parentCodePath;
}
public String getRootCode() {
return rootCode;
}
public void setRootCode(String rootCode) {
this.rootCode = rootCode;
}
public List getParentCodeNamePath() {
return parentCodeNamePath;
}
public void setParentCodeNamePath(List parentCodeNamePath) {
this.parentCodeNamePath = parentCodeNamePath;
}
} public class HorzNodeTreeUtils {
private static final Integer MAXNODELEV = 10;
private static final Integer FIRSTLEVEL = 1;
/**
* 构建树结构
*
* @return 树
*/
public static HorzDmNode buildTree(List horzDmDtoList, String rootCode) {
Map> nodeMaps = horzDmDtoList.stream().collect(Collectors.groupingBy(HorzDmDto::getParentCode));
HorzDmNode root = new HorzDmNode();
root.setCode(rootCode);
root.setRootCode(rootCode);
createTree(root, root, nodeMaps, FIRSTLEVEL);
return root;
}
/**
* 递归构建树
*
* @param parentNode parentNode
* @param nodeMaps 节点数根据parentId进行分组
* @param level 层级
* @return parentId 下的节点
*/
private static void createTree(HorzDmNode root, HorzDmNode parentNode, Map> nodeMaps, Integer level) {
if (level <= MAXNODELEV) {
if (nodeMaps.get(parentNode.getCode()) == null) {
return;
}
root.setMaxLever(level);
nodeMaps.get(parentNode.getCode()).forEach(dmDto -> {
HorzDmNode treeNode = new HorzDmNode();
treeNode.setCode(dmDto.getCode());
treeNode.setCodeName(dmDto.getCodeName());
treeNode.setLever(level);
treeNode.setSortNo(Integer.valueOf(dmDto.getCode()));
treeNode.setParentNode(parentNode);
treeNode.getParentCodePath().addAll(parentNode.getParentCodePath());
treeNode.getParentCodePath().add(parentNode.getCode());
treeNode.getParentCodeNamePath().addAll(parentNode.getParentCodeNamePath());
treeNode.getParentCodeNamePath().add(parentNode.getCodeName());
parentNode.addChild(treeNode);
createTree(root, treeNode, nodeMaps, level + 1);
});
parentNode.getChildrenNodes().sort(Comparator.comparing(HorzDmNode::getSortNo));
}
}
public static void iteratorUnit(HorzDmNode currentNode, HorzDmNode root) {
if (!root.getRootCode().equals(currentNode.getCode())) {
if (currentNode.isEndNode()) {
StringBuffer codeNameStr = new StringBuffer();
currentNode.getParentCodeNamePath().stream().filter(StringUtils::isNotEmpty).forEach(codeName -> {
codeNameStr.append(codeName).append(": ");
});
codeNameStr.append(currentNode.getCodeName());
System.out.println(codeNameStr.toString());
}
}
if (!currentNode.isEndNode()) {
List list = currentNode.getChildrenNodes();
if (list != null && list.size() > 0) {
for (HorzDmNode nodeEle : list) {
iteratorUnit(nodeEle, root);
}
}
}
if (root.getRootCode().equals(currentNode.getCode())) {
System.out.println("总记");
}
if (!root.getRootCode().equals(currentNode.getCode())) {
if (!currentNode.isEndNode()) {
StringBuffer codeNameStr = new StringBuffer();
currentNode.getParentCodeNamePath().stream().filter(StringUtils::isNotEmpty).forEach(codeName -> {
codeNameStr.append(codeName).append(": ");
});
codeNameStr.append(currentNode.getCodeName());
codeNameStr.append(": 小计");
System.out.println(codeNameStr.toString());
}
}
}
}