今天的代码中出现了class定义的类，于是网上查了一下public修饰的类于没有public修饰的类的区别。链接为：https://blog.csdn.net/jingzi123456789/article/details/71515728，学习之后总结来说如下：
1.一个 .java文件中，只能有一个public class声明的类，但是可以有多个class声明的类。即每个编译单元都有单一的公共接口，用public类实现。此时，mian()就必须要包含在public类中。
2.使用了public class定义的类，类名必须与文件名完全一致，否则编译时会出错。使用class定义的类，文件名不需要与类名相同，但是编译之后生成的文件与类名相同。如果使用class定义多个类，就会形成多个*.class文件。
3.没有public修饰的类，该类就拥有了包访问权限，即该类只可以用于该包之中。
package datastructure.list;
import javax.swing.text.Position;
/**
*
* Linked List
*
* @author WX873
*
*/
public class LinkedList {
/**
* An inner class
*/
class Node{
/**
* The data
*/
int data;
/**
* The reference to the next node.
*/
Node next;
/**
* The constructor
*
*/
public Node(int paraValue) {
// TODO Auto-generated constructor stub
data = paraValue;
next = null; //每一个节点下一个都是为空，调用的时候会指向下一个节点
}//of class Node
}//of class Node
/**
* The header node.The data is never used.
*/
Node header;
/**
* Construct an empty linked list.
*/
public LinkedList() {
// TODO Auto-generated constructor stub
header = new Node(0);
//header.next = null;
}//of the first constructor
/**
* *********************************************
* Overrides the method claimed in Object, the superclass of any class.
* *********************************************
*/
public String toString() {
String resultString = "";
if (header.next == null) {
return "empty";
}//of if
Node tempNode = header.next;
while (tempNode != null) {
resultString += tempNode.data + ",";
tempNode = tempNode.next;
}//of while
return resultString;
}//of toString
/**
* ***********************************************
* Reset to empty. Free the space through garbage collection.
* ***********************************************
*/
public void reset() {
header.next = null;
}//of reset
/**
* *********************************************************
* Locate the given value. If it appears in multiple positions,
* simply return the first one.
*
* @param paraValue The given value.
* @return The position. -1 for not found.
* *********************************************************
*/
public int locate(int paraValue) {
int tempPosition = -1;
Node tempNode = header.next;
int tempCurrentPosition = 0;
while (tempNode != null) {
if (tempNode.data == paraValue) {
tempPosition = tempCurrentPosition;
}//of if
tempCurrentPosition ++;
tempNode = tempNode.next;
}//of while
return tempPosition;
}//of locate
/**
* *************************************************
* Insert a value to a position. IF the list is already full, do nothing.
*
* @param paraPosition The given position.
* @param paraValue The given value.
* @return Success or not.
* *************************************************
*/
public boolean insert(int paraPosition, int paraValue) {
Node tempNode = header;
Node tempNewNode;
for (int i = 0; i < paraPosition; i++) {
if (tempNode.next == null) {
System.out.println("The position " + paraPosition + " is illegal.");
return false;
}//of if
tempNode = tempNode.next;
}//of for i
//Construct a new node.
tempNewNode = new Node(paraValue);
//Now link them.
tempNewNode.next = tempNode.next;
tempNode.next = tempNewNode;
return true;
}//of insert
/**
* ************************************************
* Delete a value at a position.
*
* @param paraPosition The given position.
* @return Success or not.
* ************************************************
*/
public boolean delete(int paraPosition) {
if (header.next == null) {
System.out.println("Cannot delete element from an empty list.");
return false;
}//of if
Node tempNode = header;
for (int i = 0; i < paraPosition; i++) {
if (tempNode.next.next == null) {
System.out.println("The position " + paraPosition + "is illegal.");
return false;
}//of if
tempNode = tempNode.next;
}//of for i
tempNode.next =tempNode.next.next;//跳出for循环最后一步tempNode不再自增1.
return true;
}//of delete
/**
* *********************************************
* The entrance of the program.
*
* @param args Not used now.
*
* *********************************************
*/
public static void main(String args[]) {
LinkedList tempFirstList = new LinkedList();
System.out.println("Initialized, the list is: " + tempFirstList.toString());
for (int i = 0; i < 5; i++) {
tempFirstList.insert(0, i);
}//of for i
System.out.println("Inserted, the list is: " + tempFirstList.toString());
tempFirstList.insert(5, 9);
System.out.println("Inserted, the list is: " + tempFirstList.toString());
tempFirstList.delete(4);
System.out.println("Deleted, the list is: " + tempFirstList.toString());
}//of main
}//of class LinkedList
写代码的时候有两个地方一直困惑，想通之后在相应的位置写了汉语注释。今天的学习通过手画链表才理解。自己手画的表如下图：
明天补充一个图，顺便巩固复习一下。
