Java工作中常用方法备份

在线编程地址：
http://www.runoob.com/try/runcode.php?filename=HelloWorld&type=java

import java.util.Arrays;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import java.util.HashMap;
import java.util.Map;
//http://www.guisd.com/operators.html
//134 135 136 137 138 139 150 151 152 157 158 159 187 188 147
//130 131 132 155 156 185 186 145
//133 153 180 189 

public class HelloWorld {
    public static void main(String []args) {
        String strs = "183 134 135 136 137 138 139 150 151 152 157 158 159 187 188 147 130 131 132 155 156 185 186 145 133 153 180 189";
        String[] str_arr = strs.split(" ");
        Arrays.sort(str_arr);
        System.out.println("排序后："+ Arrays.asList(str_arr));

        Map<String,String> map = new HashMap<>();
        for(int i = 0 ;i<str_arr.length;i++){
            /*判断第二个下标是否存在，不存在的话创建一个默认的*/
            if(map.get(""+str_arr[i].charAt(1))==null){ 
                map.put(""+str_arr[i].charAt(1),"");
            }
            /*根据每个手机号的第二个标识的第三个值，进行追加*/
            String value = map.get(""+str_arr[i].charAt(1));
            value += str_arr[i].charAt(2);
            map.put(""+str_arr[i].charAt(1),value);
        }
        System.out.println("根据第二位分组后结果："+ map);
        
        /*生成正则表达试*/
        String compileZ = "^1(";
        boolean isFirst = true;//首个不拼接|
        for(String key : map.keySet()){ 
            compileZ += (isFirst?"":"|") + key + "["+map.get(key)+"]";
            isFirst = false;
        }
        compileZ += ")\\d{8}$";
        System.out.println("得到的正则表达式："+ compileZ);
            
        String msg = "18311020335";//测试手机号
        Pattern pattern = Pattern.compile(compileZ);
        Matcher matcher = pattern.matcher(msg);
        boolean isMatch = matcher.matches();
        System.out.println(isMatch?"正确":"不正确");
    }
}

/**透明度对照表*/
public class HelloWorld {
    public static void main(String []args) {
        System.out.println("透明度 | 十六进制");
        System.out.println("------ | ------");
        for (double i = 1; i >= 0; i -= 0.01) {
            i = Math.round(i * 100) / 100.0d;
            int alpha = (int) Math.round(i * 255);
            String hex = Integer.toHexString(alpha).toUpperCase();
            if (hex.length() == 1) hex = "0" + hex;
            int percent = (int) (i * 100);
            System.out.println(String.format("%5d%% | %6s", percent, hex));
        }
    }
}

/**字体样式定义生成器*/
public class HelloWorld {
    public static void main(String []args) {
       for(int i =12;i<=48;i=i+2){
           int value = (int)(i*0.9);
           value = value+value%2;
           String show = "<item name=\"font_size_"+i+"\">@dimen/f_px_"+value+"</item>";
           System.out.println(show);
        }
    }
}

/**10进制转32进制，固定6位，不够前面补0方法*/
public class HelloWorld {
    public static void main(String []args) {
       for(int i =100000;i<=100050;i++){
           String str = Integer.toString(i,32);
           System.out.println(String.format("%1$6s", str).replaceAll(" ","0"));
        }
    }
}

import java.util.ArrayList;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
/**找到字符串第一个##号之间的，且不是#号的内容*/
public class HelloWorld {
    public static void main(String[] args) {
        String msg = "cssffff#aaa#ddf#ddf#fg"; 
        Pattern pattern = Pattern.compile("#[^#]+#");
        Matcher matcher = pattern.matcher(msg);
        while (matcher.find()) {
            System.out.println(matcher.group(0));
            break;//找到一个就不再继续查找
        }
    }
}

import java.util.ArrayList;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
/**找到url 的?后面的参数*/
public class HelloWorld {
public static void main(String[] args) {
String msg = "[http://www.runoob.com/try/runcode.php?filename=HelloWorld&type=java](http://www.runoob.com/try/runcode.php?filename=HelloWorld&type=java)";
Pattern pattern = Pattern.compile("\\w+=\\w");
Matcher matcher = pattern.matcher(msg);
while (matcher.find()) {
System.out.println(matcher.group(0));
//break;//找到一个就不再继续查找
}
}
}

最后编辑于：2020.05.10 07:54:04