Java学习路线-24：类库使用案例StringBuffer、Rondom、ResourceBundle、regex、Comparable

第14 章 ： 类库使用案例分析 59 StringBuffer使用

使用StringBuffer追加26个小写字母。逆序输出，并删除前5个字符 StringBuffer允许修改 String不允许修改

StringBuffer buff = new StringBuffer();
for(int i = 'a'; i    

import java.util.regex.Matcher;
import java.util.regex.Pattern;

class Demo {
    public static void main(String[] args) {
        String html  = "";
        String regex = "\\w+=\"[a-zA-Z0-9,\\+]+\"";
        Matcher matcher = Pattern.compile(regex).matcher(html);

        while (matcher.find()){
            String temp = matcher.group(0);
            String[] result = temp.split("=");
            System.out.println(result[0] + "\t" + result[1].replaceAll("\"", ""));
            /**
             * face   Arial,Serif
             * size   +2
             * color  red
             */
        }
    }
}

65 国家代码

实现国际化应用 输入国家代号，调用资源文件 3个资源文件

# message.properties
info=默认资源

# message_en_US.properties
info=英文资源

# message_zh_CN.properties
info=中文资源

import java.io.UnsupportedEncodingException;
import java.util.Locale;
import java.util.ResourceBundle;


class MessageUtil {
    // 将固定的内容定义为常量
    private static final String CHINA = "cn";
    private static final String ENGLISH = "en";
    private static final String BASENAME = "message";
    private static final String KEY = "info";

    public static String getMessage(String country) throws UnsupportedEncodingException {
        Locale locale = getLocale(country);

        if (locale == null) {
            return null;
        } else {
            ResourceBundle bundle = ResourceBundle.getBundle(BASENAME, locale);
            return new String(bundle.getString(KEY).getBytes("ISO-8859-1"), "utf-8");
        }
    }

    private static Locale getLocale(String country) {
        switch (country) {
            case CHINA:
                return new Locale("zh", "CN");
            case ENGLISH:
                return new Locale("en", "US");
            default:
                return null;
        }

    }


}

class Demo {
    public static void main(String[] args) throws UnsupportedEncodingException {
        if (args.length  other.score){
            return 1;
        } else if (this.score