trim() 方法用于删除字符串的头尾空白符。
public static void main(String[] args) {
String str = new String(" https://blog.youkuaiyun.com/lihua5419 ");
System.out.print("博客地址 :" );
System.out.println( str );
System.out.print("删除头尾空白后地址 :" );
System.out.println( str.trim() );
}