JavaSE8基础 StringBuffer delete 删除指定索引值的一个字符

package jizuiku1;

public class Demo010 {
	public static void main(String[] args) {
		StringBuffer sb = new StringBuffer();
		sb.append("cnblog_").append("jizuiku_").append("Demo");
		System.out.println(sb);
		
		//删除索引值为3的字符
		sb.deleteCharAt(3);//删的是l
		System.out.println(sb);
	}
}

    @Override
    public synchronized StringBuffer deleteCharAt(int index) {
        toStringCache = null;
        super.deleteCharAt(index);
        return this;
    }

    public AbstractStringBuilder deleteCharAt(int index) {
        if ((index < 0) || (index >= count))
            throw new StringIndexOutOfBoundsException(index);
        System.arraycopy(value, index+1, value, index, count-index-1);
        count--;
        return this;
    }