advstringtokenizer.java~17~

一个简单的数据库管理系统

package com.nay0648.util;
import java.util.*;

public class AdvStringTokenizer
{
private String origin,current;
private Set delim;

	public AdvStringTokenizer()
	{
		delim=new HashSet();
	}

	public void addDefaltDelim()
	{
		delim.add(new Character(' '));
		delim.add(new Character('\r'));
		delim.add(new Character('\n'));
		delim.add(new Character('\t'));
	}

	public void clearDelim()
	{
		delim.clear();
	}

	public void addDelim(char c)
	{
		delim.add(new Character(c));
	}

	public void removeDelim(char c)
	{
		delim.remove(new Character(c));
	}

	public boolean hasMoreTokens()
	{
		if(current.length()>0) return true;else return false;
	}

	public void setString(String s)
	{
		int i;
		origin=s;
		for(i=origin.length()-1;i>=0;i--)
			if(!delim.contains(new Character(origin.charAt(i)))) break;//cut tail
		current=origin.substring(0,i+1);
	}

	public String nextToken()
	{
		int head,tail;
		String token;

		for(head=0;head<current.length();head++)
			if(!delim.contains(new Character(origin.charAt(head)))) break;
		System.out.println("head="+head);
		for(tail=head;tail<current.length();tail++)
			if(delim.contains(new Character(origin.charAt(tail)))) break;
		System.out.println("tail="+tail);
		System.out.println("current="+current);
		token=current.substring(head,tail-head);
		current=current.substring(tail);
		return token;
	}
}