Java 字符串 之 字符串StringBuffer

http://www.verejava.com/?id=16993039377589

/**
	知识点: 可变字符串对象 StringBuffer
		1. 什么是StringBuffer
		2. 为什么用StringBuffer
			一般用在很多字符串相连接的情况
		3. StringBuffer的操作和应用
*/
public class TestStringBuffer
{
	public static void main(String[] args)
	{
		String str="";
		//实例化一个空的字符缓冲区
		StringBuffer strBuffer=new StringBuffer();
		for(int i=0;i<100;i++)
		{
			str+=i+",";
			strBuffer.append(i).append(",");
		}
		//输出字符缓冲区的字符串
		System.out.println(strBuffer.toString());

		/**
			StringBuffer的应用
		*/
		//1. 字符串追加
		StringBuffer buffer=new StringBuffer();
		buffer.append("How");
		buffer.append(" your");

		//2. 字符串的输出
		System.out.println(buffer.toString());

		//3. 字符串的替换
		buffer.replace(4,9,"you");
		System.out.println(buffer.toString());

		//4. 字符串插入索引为3的后面
		buffer.insert(3," are");
		System.out.println(buffer.toString());

		//5. 字符串的截取
		System.out.println(buffer.substring(0,4));

	}
}

http://www.verejava.com/?id=16993039377589