我昨天发布了代码的一个版本，但我认为它可以处理一些改进或什么的。事情是我再次卡住了。如您所见，我正在尝试对链表进行排序并将其写回文本文件。第一个问题是，在 Insertion 类中传递什么以及如何传递？第二个问题是如何按字母顺序实现插入排序？我已经看到了许多使用整数和数组进行插入的示例，但我似乎仍然遇到了麻烦。这是我到目前为止的进展。
编辑1：忘记这一点。
编辑 2：如何用我的方法实现 Comparable 并使用字母排序（CompareToIgnoreCase）？
主要的：
import java.io.* ;
import java.util.Scanner ;
public class Sort
{
public static void main(String[] args) throws Exception
{
File outputFile ;
Scanner kb = new Scanner (System.in) ;
LinkedList list = new LinkedList() ;
String command ;
Insertion insertion = new Insertion() ;
// Create the new text file. If exists, it will continue to the next commands
do
{
outputFile = new File("db.txt") ;
if(!outputFile.exists())
{
outputFile.createNewFile ();
System.out.println("The file was created as db.txt");
System.out.println("");
}
}while (!outputFile.exists()) ;
// Define which file to stream in from
FileInputStream fileIn = new FileInputStream("db.txt") ;
DataInputStream input = new DataInputStream (fileIn) ;
BufferedReader br = new BufferedReader (new InputStreamReader (input)) ;
String line ;
try
{
// Read each line of the file
while ((line = br.readLine()) != null)
{
list.add(line) ;
}
input.close() ;
}catch (Exception e){
System.err.println("Error. Could not read the file") ;
}
//System.out.println (list.toString()) ;
//Welcome message
System.out.println("Welcome. \nPlease use the following commands [-i for Insertion Sort, -s for Selection Sort, -m for Merge sort, Exit to terminate]: " );
System. out.println ("") ;
command = kb.next() ;
do
{
if (command.equalsIgnoreCase("-i"))
{
insertion.Sort(list, list.size()) ;
//try
//{
//the "true" argument sets the FileWriter to append mode so that is does not overwrite the first line
// BufferedWriter out = new BufferedWriter(new FileWriter("db.txt", true));
//out.write(textContent) ;
//out.newLine() ;
//out.close() ;
//}catch(IOException e)
//{
// System.out.println("Could not write to file") ;
// System.exit(0) ;
//}
//System.out.println ("Enter command:") ;
//command = kb.next() ;
}
else if (command.equalsIgnoreCase("-s"))
{
}
else if (command.equalsIgnoreCase("-m"))
{
}
else if (command.equalsIgnoreCase("Exit"))
{
System.exit(0) ;
}
else
{
System.out.println("Unknown command. Please use -i, -s, -m or EXIT") ;
command = kb.next() ;
}
}while (!command.equalsIgnoreCase("Exit")) ;
}
}
链表：
import java.lang.* ;
public class LinkedList
{
//reference to the head node
public Node head ;
public int listCount ;
//LinkedList Constructor
public LinkedList ()
{
//empty list
head = new Node (null) ;
listCount = 0 ;
}
//add element to the end of the list
public void add(String data)
{
Node temp = new Node (data) ;
Node current = head ;
//go to the end of the list
while (current.getNext() != null)
{
current = current.getNext() ;
}
// last node\s next reference is set to the last node
current.setNext(temp) ;
//increment the number of elements
listCount++ ;
}
//return the size of the list
public int size()
{
return listCount ;
}
public String toString()
{
Node current = head.getNext() ;
String output = " " ;
while (current != null)
{
output += "[" + current.getData().toString() + "]" ;
current = current.getNext() ;
}
return output ;
}
}
插入：
public class Insertion
{
public static void Sort (LinkedList listIn, int size)
{
int temp, i, j ;
for (j=1;j<size;j++)
{
while(listIn.head)
}
}
}
节点类：
public class Node
{
//reference to the next node or null if not any
Node next ;
//the entries
String data ;
//Node Constructor
public Node (String dataIn)
{
next = null ;
data = dataIn ;
}
//Node constructor in case of the need to point to a certain node
public Node (String dataIn, Node nextIn)
{
next = nextIn;
data = dataIn ;
}
public String getData ()
{
return data ;
}
public void setData (String dataIn)
{
data = dataIn ;
}
public Node getNext ()
{
return next ;
}
public void setNext (Node nextIn)
{
next = nextIn ;
}
}
}