java————串————方面的知识2

package 串;

public class StringNode {  //  节点类 结构
  public char data;
  public StringNode next;
  
  public StringNode(char c){
	  data = c;
	  next = null;
  }
   
  public StringNode(){
	  this('?');
  }
}

public class String2 {        //链式存储     实现了部分函数
   StringNode head,rear;
   int number=0;
   
   
   
   public String2(){
	   head = rear = null;
	   number = 0;
   }
   
   public String2(char c){
	   head = new StringNode(c);
	   number = 1;
   }
   
   public int length2(){
	   return number;
   }
   
   public void concat2(char c){
	   StringNode p,q;
	   if(this.head ==null){
		   head = new StringNode(c);
		   this.rear = head;
	   }else{
		   q = new StringNode(c);
		   this.rear.next = q;
		   this.rear = q;
	   }
	   number++;
   }
   
   public void concat2(String2 str){
	   StringNode q = str.head;
	   while(q!=null){
		   this.concat2(q.data);
		   q = q.next;
	   }
   }
   
   
}