packagelearning;importjava.text.NumberFormat;importjava.util.Locale;publicclassNumberFormatTest{publicstaticvoidmain(String[]args){//TODOAuto-generatedmethodstu...

packagecom.company;importjava.util.Scanner;publicclassMain{publicstaticvoidmain(String[]args){Scannerscanner=newScanner(System.in);System.out.println("yourname:...

由于客户上传图片将png的图片的后缀名改为jpg,所以通过后缀名判断不行,用下面这个方法可以//判断是否是JPG格式log.info("-1----进入JPG格式判断.....");ImageInputStreamiis=ImageIO.createImageInputStream(file.getInputStrea...

publicclassTest{publicstaticvoidmain(String[]args){StringfileName="upload/20221125/20221125563750.pdf";StringfilePath=fileName.replace("/","\");StringoldName=fi...

Runtime.getRuntime().exec(commandStr)/***Java调用CMD命令*@authorwww.51dev.com*@version2016-03-04*/publicclassDemo{publicstaticvoidmain(String[]args){Stringcommand="...

importjava.text.ParseException;importjava.text.SimpleDateFormat;importjava.util.Date;​/*日期工具类构造方法私有，成员方法静态**/publicclassDateUtil{//无参构造方法privateDateUtil(){}//定义...

packageimage;importcom.sun.image.codec.jpeg.JPEGCodec;importcom.sun.image.codec.jpeg.JPEGEncodeParam;importcom.sun.image.codec.jpeg.JPEGImageEncoder;importjava....

w把web.xml 中doctype声明部分替换掉就可以了。替换前<!DOCTYPEweb-appPUBLIC"-//SunMicrosystems,Inc.//DTDWebApplication2.3//EN""http://java.sun.com/dtd/web-app_2_3.dtd">&...

java.sun.com...

1、javac将文件编译成.class文件用法:javac其中,可能的选项包括:-g生成所有调试信息-g:none不生成任何调试信息-g:{lines,vars,source}只生成某些调试信息-nowarn不生成任何警告-verbose输出有关编译器正在执行的操作的消息-deprecation输出使用已过时的API的...

importsun.misc.BASE64Decoder;importsun.misc.BASE64Encoder;importjava.io.*;/***@authorliuzhenxing*@version1.0*@date2017/6/614:45*/publicclassImageUtil{/***@param...

importjava.util.Calendar;importjava.util.Collection;importjava.util.regex.Pattern;/***@author:wjun.java@gmail.com*@date:2015-5-24*/publicclassValidateUtil{/**字符...

java中随机生成字符串publicstaticStringgetRandomString(intlength){Stringstr="abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";Randomrandom=newRandom();Str...

packagecom.51dev;/***https://www.51dev.com*从给定数组中选出和为固定值的两个数**/publicclassTest{publicstaticvoidmain(String[]args){int[]nums={1,5,9,11,3,33,11,45,67};Testtest=ne...

//向上取整varceil=Math.ceil(5/2)console.log('++++++++++',ceil)//3//向下取整varfloor=Math.floor(5/2)console.log('----------',floor)//2//四舍五入varround1=Math.round(5/2),rou...