小编Mau*_*o M的帖子

我的朋友给我发了一个问题,他在一次模拟考试中看到了关于字符串对象的Java认证:

String makeStrings(){
    String s = "HI";
    s = s + "5";
    s = s.substring(0,1);
    s = s.toLowerCase();
    return s.toString();
}

调用此方法时将创建多少个字符串对象？考试给出的正确答案是3.但我认为这是五.

1. "HI"
2. "5"
3. "HI5"
4. "H"
5. "H"

我错了吗？

我正在使用Eclipse开发SpringMVC和Tomcat的应用程序.问题是:服务器不会更新我正在进行的更改.

一个例子:

@RequestMapping(value = "test", method = RequestMethod.GET)
    public ModelAndView test(){

        ModelAndView mv = new ModelAndView("test");                 
        System.out.println("test");
        return mv;
    }

每次我点击映射的URL时,Eclipse都会在我的控制台中打印测试.如果我注释掉println,我会得到相同的结果.

尝试解决问题:

• 清理Tomcat目录
• 重启服务器
• 关闭Eclipse
• 在"服务器"选项卡中添加/删除项目
• 删除方法正在使用的JSP
• 不同浏览器

一切都没有效果.看起来Tomcat没有更新我在代码中所做的任何更改.

我有一个类似的字符串

[{"id":"9","label":"P","price":"0","oldPrice":"0","products":["606","610","614","618","622","625","629"]},{"id":"8","label":"M","price":"0","oldPrice":"0","products":["607","611","615","619","626","630"]},{"id":"7","label":"G","price":"0","oldPrice":"0","products":["609","613","617","621","624","628","632"]},{"id":"36","label":"GG","price":"0","oldPrice":"0","products":["608","612","616","620","623","627","631"]},{"id":"152","label":"XGG","price":"0","oldPrice":"0","products":["3713","6577","6578","6579","6580","6581","6582"]}]

我需要的是标签值:P,M,G,GG,XGG.我试图在标签和逗号之间获取所有内容,但它不起作用

"(标签)(.*)(,)"

我有一个从网站中提取数据的爬虫,我得到以下字符串:

    String s = "                 --                 Android 2.3.1 (Gingerbread) --                --                  --                 --                   --                  --                  --                 --                 8" Wide LCD - tela sensível ao toque (resistiva) --                 --                 800 x 600 (4:3) --                --                  --                 --                   --                  --                  --                 --                 1,2 GHz ARM Cortex A8 Core (RK2918) --               --                 4 GB (Memória Flash) e DRAM 512 Mb, DDR3 --                  --                 Slot para cartão Micro SD (Máx. 32 GB) --                --                 Integrado, suporta rotação de tela --                --                 Sim --               -- …