String的trim方法

Java String trim
val[st] <= ’ ‘ 除去头尾ASCII码小于空格（32）的字符
一直记为只去除头尾的空格，有空还是要多看看源码

public String trim() {        int len = value.length;        int st = 0;        char[] val = value;    /* avoid getfield opcode */        while ((st < len) && (val[st] <= ' ')) {            st++;        }        while ((st < len) && (val[len - 1] <= ' ')) {            len--;        }        return ((st > 0) || (len < value.length)) ? substring(st, len) : this;    }

TEST

public static void Str() {        char[] c = new char[] { '\t', 'a'};        String str = new String(c);        System.out.println("{" + str + "}");        str = str.trim();        System.out.println("{" + str + "}");        }

OUTPUT

{   a}{a}