java 常用工具类 (值得收藏)

package org.fh.util;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.util.Random;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

/**
 * 说明：常用工具
 * 作者：FH Admin
 * from：fhadmin.cn
 */
public class Tools {
    
    /**
     * 随机生成六位数验证码 
     * @return
     */
    public static int getRandomNum(){
         Random r = new Random();
         return r.nextInt(900000)+100000;//(Math.random()*(999999-100000)+100000)
    }
    
    /**
     * 随机生成四位数验证码 
     * @return
     */
    public static int getRandomNum4(){
         Random r = new Random();
         return r.nextInt(9000)+1000;
    }
    
    /**
     * 随机生成两位数验证码 
     * @return
     */
    public static int getRandomNum2(){
         Random r = new Random();
         return r.nextInt(90)+10;
    }
    
    /**
     * 检测字符串是否不为空(null,\"\",\"null\")
     * @param s
     * @return 不为空则返回true，否则返回false
     */
    public static boolean notEmpty(String s){
        return s!=null && !\"\".equals(s) && !\"null\".equals(s);
    }
    
    /**
     * 检测字符串是否为空(null,\"\",\"null\")
     * @param s
     * @return 为空则返回true，不否则返回false
     */
    public static boolean isEmpty(String s){
        return s==null || \"\".equals(s) || \"null\".equals(s);
    }
    
    /**
     * 字符串转换为字符串数组
     * @param str 字符串
     * @param splitRegex 分隔符
     * @return
     */
    public static String[] str2StrArray(String str,String splitRegex){
        if(isEmpty(str)){
            return null;
        }
        return str.split(splitRegex);
    }
    
    /**
     * 用默认的分隔符(,)将字符串转换为字符串数组
     * @param str    字符串
     * @return
     */
    public static String[] str2StrArray(String str){
        return str2StrArray(str,\",\\\\s*\");
    }
    
    /**
     * 往文件里的内容
     * @param filePath  文件路径
     * @param content  写入的内容
     */
    public static void writeFile(String fileP,String content){
        String filePath = String.valueOf(Thread.currentThread().getContextClassLoader().getResource(\"\"))+\"../../\";    //项目路径
        filePath = filePath.replaceAll(\"file:/\", \"\");
        filePath = filePath.replaceAll(\"%20\", \" \");
        filePath = filePath.trim() + fileP.trim();
        if(filePath.indexOf(\":\") != 1){
            filePath = File.separator + filePath;
        }
        try {
            OutputStreamWriter write = new OutputStreamWriter(new FileOutputStream(filePath),\"utf-8\");      
            BufferedWriter writer=new BufferedWriter(write);          
            writer.write(content);      
            writer.close(); 
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    
    /**
     * 往文件里的内容（Projectpath下）
     * @param filePath  文件路径
     * @param content  写入的内容
     */
    public static void writeFileCR(String fileP,String content){
        String filePath = PathUtil.getProjectpath() + fileP;
        try {
            OutputStreamWriter write = new OutputStreamWriter(new FileOutputStream(filePath),\"utf-8\");      
            BufferedWriter writer=new BufferedWriter(write);          
            writer.write(content);      
            writer.close(); 
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    
    /**
      * 验证邮箱
      * @param email
      * @return
      */
     public static boolean checkEmail(String email){
      boolean flag = false;
      try{
        String check = \"^([a-z0-9A-Z]+[-|_|\\\\.]?)+[a-z0-9A-Z]@([a-z0-9A-Z]+(-[a-z0-9A-Z]+)?\\\\.)+[a-zA-Z]{2,}$\";
        Pattern regex = Pattern.compile(check);
        Matcher matcher = regex.matcher(email);
        flag = matcher.matches();
       }catch(Exception e){
        flag = false;
       }
      return flag;
     }
    
     /**
      * 验证手机号码
      * @param mobiles
      * @return
      */
     public static boolean checkMobileNumber(String mobileNumber){
      boolean flag = false;
      try{
        Pattern regex = Pattern.compile(\"^(((13[0-9])|(15([0-3]|[5-9]))|(18[0,5-9]))\\\\d{8})|(0\\\\d{2}-\\\\d{8})|(0\\\\d{3}-\\\\d{7})$\");
        Matcher matcher = regex.matcher(mobileNumber);
        flag = matcher.matches();
       }catch(Exception e){
        flag = false;
       }
      return flag;
     }
     
    /**
     * 检测KEY是否正确
     * @param paraname  传入参数
     * @param FKEY        接收的 KEY
     * @return 为空则返回true，不否则返回false
     */
    public static boolean checkKey(String paraname, String FKEY){
        paraname = (null == paraname)? \"\":paraname;
        return MD5.md5(paraname+DateUtil.getDays()+\",fh,\").equals(FKEY);
    }
    
    /**读取txt里的全部内容
     * @param fileP  文件路径
     * @param encoding  编码
     * @return
     */
    public static String readTxtFileAll(String fileP, String encoding) {
        StringBuffer fileContent = new StringBuffer(); 
        try {
            String filePath = String.valueOf(Thread.currentThread().getContextClassLoader().getResource(\"\"))+\"../../\";    //项目路径
            filePath = filePath.replaceAll(\"file:/\", \"\");
            filePath = filePath.replaceAll(\"%20\", \" \");
            filePath = filePath.trim() + fileP.trim();
            if(filePath.indexOf(\":\") != 1){
                filePath = File.separator + filePath;
            }
            File file = new File(filePath);
            if (file.isFile() && file.exists()) {         // 判断文件是否存在
                InputStreamReader read = new InputStreamReader(
                new FileInputStream(file), encoding);    // 考虑到编码格式
                BufferedReader bufferedReader = new BufferedReader(read);
                String lineTxt = null;
                while ((lineTxt = bufferedReader.readLine()) != null) {
                    fileContent.append(lineTxt);
                    fileContent.append(\"\\n\");
                }
                read.close();
            }else{
                System.out.println(\"找不到指定的文件,查看此路径是否正确:\"+filePath);
            }
        } catch (Exception e) {
            System.out.println(\"读取文件内容出错\");
        }
        return fileContent.toString();
    }
    
    /**
     * 读取Projectpath某文件里的全部内容
     * @param filePath  文件路径
     */
    public static String readFileAllContent(String fileP) {
        StringBuffer fileContent = new StringBuffer(); 
        try {
            String encoding = \"utf-8\";
            File file = new File(PathUtil.getProjectpath() + fileP);//文件路径
            if (file.isFile() && file.exists()) {         // 判断文件是否存在
                InputStreamReader read = new InputStreamReader(
                new FileInputStream(file), encoding);    // 考虑到编码格式
                BufferedReader bufferedReader = new BufferedReader(read);
                String lineTxt = null;
                while ((lineTxt = bufferedReader.readLine()) != null) {
                    fileContent.append(lineTxt);
                    fileContent.append(\"\\n\");
                }
                read.close();
            }else{
                System.out.println(\"找不到指定的文件,查看此路径是否正确:\"+fileP);
            }
        } catch (Exception e) {
            System.out.println(\"读取文件内容出错\");
        }
        return fileContent.toString();
    }
    
    public static void main(String[] args) {
        System.out.println(getRandomNum());
    }
    
}
 

来源：https://www.cnblogs.com/m13002622490/p/16003125.html
本站部分图文来源于网络，如有侵权请联系删除。