将 inOrderTraversal 方法的内容放入文件时出现问题

Question

我一直在尝试获取它，以便该方法返回一个字符串，但它抛出了一堆错误。我需要将 inOrderTraversal 方法内容放入文件中或以某种方式存储它，以便我可以将其写入文件。如果有人能帮助我，我将不胜感激！谢谢！！

public class BinaryTree {
// Tree: simplest possible binary search tree
private Node root; // hidden root node
// inorderTraversal: need because root is hidden
public void inorderTraversal() {
inorderT(root);
}
// inorderT: recursive function that does the work
private void inorderT(Node node) {
if (node != null) {
inorderT(node.left);
System.out.println(node.data+" ");
//node.data = node.data+" ";
inorderT(node.right);
}
}
========================================================================================================
public static void main(String ... args) throws IOException {
System.out.println("Starting");
File file = new File("C:\Users\Marlene\Workspace\BinaryTree\src\com\company\unsorteddict.txt");
Scanner scan = new Scanner(file);
//Creation of linked list and line variable
String fileContents = "";
LinkedList<String> linkedList = new LinkedList<>();
BinaryTree tree = new BinaryTree();
int lineNum = 0;
//Writing contents into a file
PrintWriter writer = new PrintWriter("C:\Users\Marlene\Workspace\BinaryTree\src\com\company\sorteddict.txt", "UTF-8");
while(scan.hasNextLine()){
fileContents = scan.nextLine();
lineNum++;
int x = 0;
if (linkedList.size() == 0) {
linkedList.add(0, fileContents);
}
else {
for (int i = 0; i < linkedList.size(); i++) {
tree.insert(fileContents);
}
}
}
tree.inorderTraversal(); //NEED TO PUT THIS LINE INTO A FILE
System.out.println("Ended");
}

Answer 1

您可以将writer对象传递给inorderTraversal()方法以及inorderT()方法，并将顺序遍历节点数据写入文件中。

public class BinaryTree {
// Tree: simplest possible binary search tree
private Node root; // hidden root node
// inorderTraversal: need because root is hidden
public void inorderTraversal(PrintWriter writer) {
inorderT(root, writer);
}
// inorderT: recursive function that does the work
private void inorderT(Node node, PrintWriter writer) {
if (node != null) {
inorderT(node.left, writer);
System.out.println(node.data+" ");
//node.data = node.data+" ";
writer.println(node.data+" ");    // Here, write to the file.
inorderT(node.right, writer);
}
}
public static void main(String ... args) throws IOException {
System.out.println("Starting");
File file = new File("C:\Users\Marlene\Workspace\BinaryTree\src\com\company\unsorteddict.txt");
Scanner scan = new Scanner(file);
//Creation of linked list and line variable
String fileContents = "";
LinkedList<String> linkedList = new LinkedList<>();
BinaryTree tree = new BinaryTree();
int lineNum = 0;
//Writing contents into a file
PrintWriter writer = new PrintWriter("C:\Users\Marlene\Workspace\BinaryTree\src\com\company\sorteddict.txt", "UTF-8");
while(scan.hasNextLine()){
fileContents = scan.nextLine();
lineNum++;
int x = 0;
if (linkedList.size() == 0) {
linkedList.add(0, fileContents);
}
else {
for (int i = 0; i < linkedList.size(); i++) {
tree.insert(fileContents);
}
}
}
tree.inorderTraversal(writer); //NEED TO PUT THIS LINE INTO A FILE
System.out.println("Ended");
}