我想从字符串中创建并打印一个从文件中读取的树。我尝试了以下代码，但无法以正确的方式打印树。
我有文件file.txt，例如以下字符串
COM-博新闻2012,12
COM-博新闻2015,3
净PHP-WWW，20
净phototrails，3个
我想创建一个像
这样的树 root
|
com(17) //calculated as (2+12+3)
|bo(17)
|news(17)
|2012 (12)
|2015(3)
|net(23)
|php(20)
|www(20)
|phototrails(3)
我尝试了以下代码
public void ReadFile(String inputFile){
Map<String[],Integer> map = new HashMap<String[], Integer>();
BufferedReader br=null;
String file1 = "";
try {
br = new BufferedReader(new FileReader(inputFile));
while ((file1 = br.readLine()) != null) {
String path[]=file1.split(",");
String nodes[]=path[0].split("-");
map.put(nodes,Integer.parseInt(path[1].trim()));
}
buildTree(map);
br.close();
}catch(Exception e){
System.out.println(e);
}
}
public void buildTree(Map<String[],Integer> map)
{
Map<String, Node> wordMap = new HashMap<String, Node>();
Node root = new Node();
for (Map.Entry<String[], Integer> entry : map.entrySet()) {
String key[] = entry.getKey();
Integer value = entry.getValue();
Node current=root;
Node p;
for(String node:key)
{
if(wordMap.containsKey(node)){
p = wordMap.get(node);
p.addCost(value);
} else {
p=new Node(node,value);
wordMap.put(node, p);
System.out.println("AddNode: "+p.getName());
}
current.addChild(p);
current = p;
}
}
printTree(root);
}
public void printTree(Node doc) { ///print tree
if (doc == null) {
System.out.println("Nothing to print!!");
return;
}
try {
System.out.println(doc.getName() + " " + doc.getCount());
List<Node> cl = doc.getChildren();
for (int i = 0; i < cl.size(); i++) {
Node node = cl.get(i);
System.out.println(
"\t" + node.getName() + " ->" + node.getCount());
}
List<Node> nl = doc.getChildren();
for (int i = 0; i < nl.size(); i++) {
Node node = nl.get(i);
printTree(node);
}
} catch (Throwable e) {
System.out.println("Cannot print!! " + e.getMessage());
}
}
public class Node {
private String name;
private int count;
private List<Node> children;
public Node() {
this(null, 0);
}
public Node(String name, int count) {
this.name = name;
this.count = count;
this.children = new ArrayList<Node>();
}
public Node(String name) {
this.name = name;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getCount() {
return count;
}
public void setCount(int count) {
this.count = count;
}
public List<Node> getChildren() {
return children;
}
public void setChildren(List<Node> children) {
this.children = children;
}
public void addChild(Node n) {
for (Node nn : children) {
if (nn.name.equals(n.name)) {
return;
}
}
this.children.add(n);
}
public void addCost(int i) {
this.count += i;
}
}
但我无法以正确的方式打印树。当它与孩子一样获得相同的节点时，它有时会产生无限循环。有人可以指导我吗？感谢。
答案 0 :(得分：1)
我添加了生成Tree类结构的代码，使用了复合模式。
package com.test;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
public class TestMain {
public static void main(String[] args) {
TestMain testMain = new TestMain();
List<String> testData = new ArrayList<String>();
testData.add("com-bo-news-2012,12");
testData.add("com-bo-news-2015,3");
testData.add("net-php-www,20");
testData.add("net-phototrails,3");
MyNode myNode = new MyNode("ROOT");
for (String string : testData) {
List<String> l = new ArrayList<String>();
l.addAll(Arrays.asList(string.split("-")));
testMain.buildTree(l, myNode);
}
printTree(myNode, 1);
}
private void buildTree(List<String> nodeNames, MyNode node) {
if (nodeNames.isEmpty()) {
return;
}
String nodeName = nodeNames.remove(0);
MyNode myNode = new MyNode(nodeName);
int index = node.getNodes().indexOf(myNode);
if (index == -1) {
node.getNodes().add(myNode);
} else {
myNode = node.getNodes().get(index);
}
buildTree(nodeNames, myNode);
}
private static void printTree(MyNode myNode, int tabCount) {
for (int i = 0; i < tabCount; i++) {
System.out.print("\t");
}
System.out.print(myNode.getNode() + "\n");
for (int i = 0; i < tabCount; i++) {
System.out.print("\t");
}
System.out.println("|");
for (MyNode node : myNode.getNodes()) {
printTree(node, ++tabCount);
}
}
}
package com.test;
import java.util.ArrayList;
import java.util.List;
public class MyNode {
private String node;
private List<MyNode> nodes;
public MyNode(String node) {
super();
this.node = node;
this.nodes = new ArrayList<MyNode>();
}
public MyNode(String node, List<MyNode> nodes) {
super();
this.node = node;
this.nodes = nodes;
}
public String getNode() {
return node;
}
public void setNode(String node) {
this.node = node;
}
public List<MyNode> getNodes() {
return nodes;
}
public void setNodes(List<MyNode> nodes) {
this.nodes = nodes;
}
@Override
public int hashCode() {
return node.hashCode();
}
@Override
public boolean equals(Object obj) {
if (obj == null) {
return false;
}
if (getClass().equals(obj.getClass())) {
return ((MyNode) obj).getNode().equals(node);
}
return false;
}
@Override
public String toString() {
return node + "[" + nodes.size()+"]";
}
}
输出需要格式化一点，如果您有任何疑问，请告诉我