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log4j.properties使用

TNT — Thu, 16 Aug 2007 03:19:00 GMT

log4j.properties 使用
一.参数意义说明
输出级别的种类
ERROR、WARN、INFO、DEBUG
ERROR 为严重错误主要是程序的错误
WARN 为一般警告，比如session丢失
INFO 为一般要显示的信息，比如登录登出
DEBUG 为程序的调试信息

配置日志信息输出目的地
log4j.appender.appenderName = fully.qualified.name.of.appender.class
1.org.apache.log4j.ConsoleAppender（控制台）
2.org.apache.log4j.FileAppender（文件）
3.org.apache.log4j.DailyRollingFileAppender（每天产生一个日志文件）
4.org.apache.log4j.RollingFileAppender（文件大小到达指定尺寸的时候产生一个新的文件）
5.org.apache.log4j.WriterAppender（将日志信息以流格式发送到任意指定的地方）

配置日志信息的格式
log4j.appender.appenderName.layout = fully.qualified.name.of.layout.class
1.org.apache.log4j.HTMLLayout（以HTML表格形式布局），
2.org.apache.log4j.PatternLayout（可以灵活地指定布局模式），
3.org.apache.log4j.SimpleLayout（包含日志信息的级别和信息字符串），
4.org.apache.log4j.TTCCLayout（包含日志产生的时间、线程、类别等等信息）

控制台选项
Threshold=DEBUG:指定日志消息的输出最低层次。
ImmediateFlush=true:默认值是true,意谓着所有的消息都会被立即输出。
Target=System.err：默认情况下是：System.out,指定输出控制台

FileAppender 选项
Threshold=DEBUF:指定日志消息的输出最低层次。
ImmediateFlush=true:默认值是true,意谓着所有的消息都会被立即输出。
File=mylog.txt:指定消息输出到mylog.txt文件。
Append=false:默认值是true,即将消息增加到指定文件中，false指将消息覆盖指定的文件内容。

RollingFileAppender 选项
Threshold=DEBUG:指定日志消息的输出最低层次。
ImmediateFlush=true:默认值是true,意谓着所有的消息都会被立即输出。
File=mylog.txt:指定消息输出到mylog.txt文件。
Append=false:默认值是true,即将消息增加到指定文件中，false指将消息覆盖指定的文件内容。
MaxFileSize=100KB: 后缀可以是KB, MB 或者是 GB. 在日志文件到达该大小时，将会自动滚动，即将原来的内容移到mylog.log.1文件。
MaxBackupIndex=2:指定可以产生的滚动文件的最大数。

log4j.appender.A1.layout.ConversionPattern=%-4r %-5p %d{yyyy-MM-dd HH:mm:ssS} %c %m%n
日志信息格式中几个符号所代表的含义：
-X号: X信息输出时左对齐；
%p: 输出日志信息优先级，即DEBUG，INFO，WARN，ERROR，FATAL,
%d: 输出日志时间点的日期或时间，默认格式为ISO8601，也可以在其后指定格式，比如：%d{yyy MMM dd HH:mm:ss,SSS}，输出类似：2002年10月18日 22：10：28，921
%r: 输出自应用启动到输出该log信息耗费的毫秒数
%c: 输出日志信息所属的类目，通常就是所在类的全名
%t: 输出产生该日志事件的线程名
%l: 输出日志事件的发生位置，相当于%C.%M(%F:%L)的组合,包括类目名、发生的线程，以及在代码中的行数。举例：Testlog4.main (TestLog4.java:10)
%x: 输出和当前线程相关联的NDC(嵌套诊断环境),尤其用到像java servlets这样的多客户多线程的应用中。
%%: 输出一个"%"字符
%F: 输出日志消息产生时所在的文件名称
%L: 输出代码中的行号
%m: 输出代码中指定的消息,产生的日志具体信息
%n: 输出一个回车换行符，Windows平台为"\r\n"，Unix平台为"\n"输出日志信息换行
可以在%与模式字符之间加上修饰符来控制其最小宽度、最大宽度、和文本的对齐方式。如：
1)%20c：指定输出category的名称，最小的宽度是20，如果category的名称小于20的话，默认的情况下右对齐。
2)%-20c:指定输出category的名称，最小的宽度是20，如果category的名称小于20的话，"-"号指定左对齐。
3)%.30c:指定输出category的名称，最大的宽度是30，如果category的名称大于30的话，就会将左边多出的字符截掉，但小于30的话也不会有空格。
4)%20.30c:如果category的名称小于20就补空格，并且右对齐，如果其名称长于30字符，就从左边较远输出的字符截掉。

二.文件配置Sample1
log4j.rootLogger=DEBUG,A1,R
#log4j.rootLogger=INFO,A1,R

# ConsoleAppender 输出
log4j.appender.A1=org.apache.log4j.ConsoleAppender
log4j.appender.A1.layout=org.apache.log4j.PatternLayout
log4j.appender.A1.layout.ConversionPattern=%-d{yyyy-MM-dd HH:mm:ss,SSS} [%c]-[%p] %m%n

# File 输出一天一个文件,输出路径可以定制,一般在根路径下
log4j.appender.R=org.apache.log4j.DailyRollingFileAppender
log4j.appender.R.File=blog_log.txt
log4j.appender.R.MaxFileSize=500KB
log4j.appender.R.MaxBackupIndex=10
log4j.appender.R.layout=org.apache.log4j.PatternLayout
log4j.appender.R.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss,SSS} [%t] [%c] [%p] - %m%n

文件配置Sample2
下面给出的Log4J配置文件实现了输出到控制台，文件，回滚文件，发送日志邮件，输出到数据库日志表，自定义标签等全套功能。
log4j.rootLogger=DEBUG,CONSOLE,A1,im
#DEBUG,CONSOLE,FILE,ROLLING_FILE,MAIL,DATABASE

log4j.addivity.org.apache=true

###################
# Console Appender
###################
log4j.appender.CONSOLE=org.apache.log4j.ConsoleAppender
log4j.appender.Threshold=DEBUG
log4j.appender.CONSOLE.Target=System.out
log4j.appender.CONSOLE.layout=org.apache.log4j.PatternLayout
log4j.appender.CONSOLE.layout.ConversionPattern=[framework] %d - %c -%-4r [%t] %-5p %c %x - %m%n
#log4j.appender.CONSOLE.layout.ConversionPattern=[start]%d{DATE}[DATE]%n%p[PRIORITY]%n%x[NDC]%n%t[THREAD] n%c[CATEGORY]%n%m[MESSAGE]%n%n

#####################
# File Appender
#####################
log4j.appender.FILE=org.apache.log4j.FileAppender
log4j.appender.FILE.File=file.log
log4j.appender.FILE.Append=false
log4j.appender.FILE.layout=org.apache.log4j.PatternLayout
log4j.appender.FILE.layout.ConversionPattern=[framework] %d - %c -%-4r [%t] %-5p %c %x - %m%n
# Use this layout for LogFactor 5 analysis

########################
# Rolling File
########################
log4j.appender.ROLLING_FILE=org.apache.log4j.RollingFileAppender
log4j.appender.ROLLING_FILE.Threshold=ERROR
log4j.appender.ROLLING_FILE.File=rolling.log
log4j.appender.ROLLING_FILE.Append=true
log4j.appender.ROLLING_FILE.MaxFileSize=10KB
log4j.appender.ROLLING_FILE.MaxBackupIndex=1
log4j.appender.ROLLING_FILE.layout=org.apache.log4j.PatternLayout
log4j.appender.ROLLING_FILE.layout.ConversionPattern=[framework] %d - %c -%-4r [%t] %-5p %c %x - %m%n

####################
# Socket Appender
####################
log4j.appender.SOCKET=org.apache.log4j.RollingFileAppender
log4j.appender.SOCKET.RemoteHost=localhost
log4j.appender.SOCKET.Port=5001
log4j.appender.SOCKET.LocationInfo=true
# Set up for Log Facter 5
log4j.appender.SOCKET.layout=org.apache.log4j.PatternLayout
log4j.appender.SOCET.layout.ConversionPattern=[start]%d{DATE}[DATE]%n%p[PRIORITY]%n%x[NDC]%n%t[THREAD]%n%c[CATEGORY]%n%m[MESSAGE]%n%n

########################
# Log Factor 5 Appender
########################
log4j.appender.LF5_APPENDER=org.apache.log4j.lf5.LF5Appender
log4j.appender.LF5_APPENDER.MaxNumberOfRecords=2000

########################
# SMTP Appender
#######################
log4j.appender.MAIL=org.apache.log4j.net.SMTPAppender
log4j.appender.MAIL.Threshold=FATAL
log4j.appender.MAIL.BufferSize=10
log4j.appender.MAIL.From=chenyl@hollycrm.com
log4j.appender.MAIL.SMTPHost=mail.hollycrm.com
log4j.appender.MAIL.Subject=Log4J Message
log4j.appender.MAIL.To=chenyl@hollycrm.com
log4j.appender.MAIL.layout=org.apache.log4j.PatternLayout
log4j.appender.MAIL.layout.ConversionPattern=[framework] %d - %c -%-4r [%t] %-5p %c %x - %m%n

########################
# JDBC Appender
#######################
log4j.appender.DATABASE=org.apache.log4j.jdbc.JDBCAppender
log4j.appender.DATABASE.URL=jdbc:mysql://localhost:3306/test
log4j.appender.DATABASE.driver=com.mysql.jdbc.Driver
log4j.appender.DATABASE.user=root
log4j.appender.DATABASE.password=
log4j.appender.DATABASE.sql=INSERT INTO LOG4J (Message) VALUES ('[framework] %d - %c -%-4r [%t] %-5p %c %x - %m%n')
log4j.appender.DATABASE.layout=org.apache.log4j.PatternLayout
log4j.appender.DATABASE.layout.ConversionPattern=[framework] %d - %c -%-4r [%t] %-5p %c %x - %m%n

log4j.appender.A1=org.apache.log4j.DailyRollingFileAppender
log4j.appender.A1.File=SampleMessages.log4j
log4j.appender.A1.DatePattern=yyyyMMdd-HH'.log4j'
log4j.appender.A1.layout=org.apache.log4j.xml.XMLLayout

###################
#自定义Appender
###################
log4j.appender.im = net.cybercorlin.util.logger.appender.IMAppender

log4j.appender.im.host = mail.cybercorlin.net
log4j.appender.im.username = username
log4j.appender.im.password = password
log4j.appender.im.recipient = corlin@cybercorlin.net

log4j.appender.im.layout=org.apache.log4j.PatternLayout
log4j.appender.im.layout.ConversionPattern =[framework] %d - %c -%-4r [%t] %-5p %c %x - %m%n

三.高级使用
实验目的：
1.把FATAL级错误写入2000NT日志
2. WARN，ERROR，FATAL级错误发送email通知管理员
3.其他级别的错误直接在后台输出

实验步骤：
输出到2000NT日志
1.把Log4j压缩包里的NTEventLogAppender.dll拷到WINNT\SYSTEM32目录下
2.写配置文件log4j.properties

# 在2000系统日志输出
log4j.logger.NTlog=FATAL, A8
# APPENDER A8
log4j.appender.A8=org.apache.log4j.nt.NTEventLogAppender
log4j.appender.A8.Source=JavaTest
log4j.appender.A8.layout=org.apache.log4j.PatternLayout
log4j.appender.A8.layout.ConversionPattern=%-4r %-5p [%t] %37c %3x - %m%n

3.调用代码：
Logger logger2 = Logger.getLogger("NTlog"); //要和配置文件中设置的名字相同
logger2.debug("debug!!!");
logger2.info("info!!!");
logger2.warn("warn!!!");
logger2.error("error!!!");
//只有这个错误才会写入2000日志
logger2.fatal("fatal!!!");

发送email通知管理员：
1. 首先下载JavaMail和JAF,
http://java.sun.com/j2ee/ja/javamail/index.html
http://java.sun.com/beans/glasgow/jaf.html
在项目中引用mail.jar和activation.jar。
2. 写配置文件
# 将日志发送到email
log4j.logger.MailLog=WARN,A5
# APPENDER A5
log4j.appender.A5=org.apache.log4j.net.SMTPAppender
log4j.appender.A5.BufferSize=5
log4j.appender.A5.To=chunjie@263.net
log4j.appender.A5.From=error@error.com
log4j.appender.A5.Subject=ErrorLog
log4j.appender.A5.SMTPHost=smtp.263.net
log4j.appender.A5.layout=org.apache.log4j.PatternLayout
log4j.appender.A5.layout.ConversionPattern=%-4r %-5p [%t] %37c %3x - %m%n
3.调用代码：
//把日志发送到mail
Logger logger3 = Logger.getLogger("MailLog");
logger3.warn("warn!!!");
logger3.error("error!!!");
logger3.fatal("fatal!!!");

在后台输出所有类别的错误：
1. 写配置文件
# 在后台输出
log4j.logger.console=DEBUG, A1
# APPENDER A1
log4j.appender.A1=org.apache.log4j.ConsoleAppender
log4j.appender.A1.layout=org.apache.log4j.PatternLayout
log4j.appender.A1.layout.ConversionPattern=%-4r %-5p [%t] %37c %3x - %m%n
2．调用代码
Logger logger1 = Logger.getLogger("console");
logger1.debug("debug!!!");
logger1.info("info!!!");
logger1.warn("warn!!!");
logger1.error("error!!!");
logger1.fatal("fatal!!!");

--------------------------------------------------------------------
全部配置文件：log4j.properties
# 在后台输出
log4j.logger.console=DEBUG, A1
# APPENDER A1
log4j.appender.A1=org.apache.log4j.ConsoleAppender
log4j.appender.A1.layout=org.apache.log4j.PatternLayout
log4j.appender.A1.layout.ConversionPattern=%-4r %-5p [%t] %37c %3x - %m%n

# 将日志发送到email
log4j.logger.MailLog=WARN,A5
# APPENDER A5
log4j.appender.A5=org.apache.log4j.net.SMTPAppender
log4j.appender.A5.BufferSize=5
log4j.appender.A5.To=chunjie@263.net
log4j.appender.A5.From=error@error.com
log4j.appender.A5.Subject=ErrorLog
log4j.appender.A5.SMTPHost=smtp.263.net
log4j.appender.A5.layout=org.apache.log4j.PatternLayout
log4j.appender.A5.layout.ConversionPattern=%-4r %-5p [%t] %37c %3x - %m%n

全部代码：Log4jTest.java

/*
* 创建日期 2003-11-13
*/
package edu.bcu.Bean;
import org.apache.log4j.*;
//import org.apache.log4j.nt.*;
//import org.apache.log4j.net.*;
/**
* @author yanxu
*/
public class Log4jTest
{
public static void main(String args[])
{
   PropertyConfigurator.configure("log4j.properties");
   //在后台输出
   Logger logger1 = Logger.getLogger("console");
   logger1.debug("debug!!!");
   logger1.info("info!!!");
   logger1.warn("warn!!!");
   logger1.error("error!!!");
   logger1.fatal("fatal!!!");

   //在NT系统日志输出
   Logger logger2 = Logger.getLogger("NTlog");
   //NTEventLogAppender nla = new NTEventLogAppender();
   logger2.debug("debug!!!");
   logger2.info("info!!!");
   logger2.warn("warn!!!");
   logger2.error("error!!!");
   //只有这个错误才会写入2000日志
   logger2.fatal("fatal!!!");

   //把日志发送到mail
   Logger logger3 = Logger.getLogger("MailLog");
   //SMTPAppender sa = new SMTPAppender();
   logger3.warn("warn!!!");
   logger3.error("error!!!");
   logger3.fatal("fatal!!!");
}
}

TNT 2007-08-16 11:19 发表评论

Java日期操作常用方法

TNT — Wed, 19 Jul 2006 04:15:00 GMT

取得指定月份的第一天与取得指定月份的最后一天
http://iamin.blogdriver.com/iamin/847990.html
/**
* 取得指定月份的第一天
*
* @param strdate String
* @return String
*/
public String getMonthBegin(String strdate)
{
java.util.Date date = parseFormatDate(strdate);
return formatDateByFormat(date,"yyyy-MM") + "-01";
}

/**
* 取得指定月份的最后一天
*
* @param strdate String
* @return String
*/
public String getMonthEnd(String strdate)
{
java.util.Date date = parseFormatDate(getMonthBegin(strdate));
Calendar calendar = Calendar.getInstance();
calendar.setTime(date);
calendar.add(Calendar.MONTH,1);
calendar.add(Calendar.DAY_OF_YEAR, -1);
return formatDate(calendar.getTime());
}

/**
* 常用的格式化日期
*
* @param date Date
* @return String
*/
public String formatDate(java.util.Date date)
{
return formatDateByFormat(date,"yyyy-MM-dd");
}

/**
* 以指定的格式来格式化日期
*
* @param date Date
* @param format String
* @return String
*/
public String formatDateByFormat(java.util.Date date,String format)
{
String result = "";
if(date != null)
{
try
{
SimpleDateFormat sdf = new SimpleDateFormat(format);
result = sdf.format(date);
}
catch(Exception ex)
{
LOGGER.info("date:" + date);
ex.printStackTrace();
}
}
return result;
}
---------------------------------------------------------------

package com.app.util;

/**
* 日期操作
*
* @author xxx
* @version 2.0 jdk1.4.0 tomcat5.1.0 * Updated Date:2005/03/10
*/
public class DateUtil {
           /**
            * 格式化日期
            *
            * @param dateStr
            * 字符型日期
            * @param format
            * 格式
            * @return 返回日期
            */
           public static java.util.Date parseDate(String dateStr, String format) {
                       java.util.Date date = null;
                       try {
                                   java.text.DateFormat df = new java.text.SimpleDateFormat(format);
                                   String dt=Normal.parse(dateStr).replaceAll(
                                                           "-", "/");
                                   if((!dt.equals(""))&&(dt.length()                                                dt+=format.substring(dt.length()).replaceAll("[YyMmDdHhSs]","0");
                                   }
                                   date = (java.util.Date) df.parse(dt);
                       } catch (Exception e) {
                       }
                       return date;
           }

           public static java.util.Date parseDate(String dateStr) {
                       return parseDate(dateStr, "yyyy/MM/dd");
           }

           public static java.util.Date parseDate(java.sql.Date date) {
                       return date;
           }

           public static java.sql.Date parseSqlDate(java.util.Date date) {
                       if (date != null)
                                   return new java.sql.Date(date.getTime());
                       else
                                   return null;
           }

           public static java.sql.Date parseSqlDate(String dateStr, String format) {
                       java.util.Date date = parseDate(dateStr, format);
                       return parseSqlDate(date);
           }

           public static java.sql.Date parseSqlDate(String dateStr) {
                       return parseSqlDate(dateStr, "yyyy/MM/dd");
           }


           public static java.sql.Timestamp parseTimestamp(String dateStr,
                                   String format) {
                       java.util.Date date = parseDate(dateStr, format);
                       if (date != null) {
                                   long t = date.getTime();
                                   return new java.sql.Timestamp(t);
                       } else
                                   return null;
           }

           public static java.sql.Timestamp parseTimestamp(String dateStr) {
                       return parseTimestamp(dateStr, "yyyy/MM/dd HH:mm:ss");
           }

           /**
            * 格式化输出日期
            *
            * @param date
            * 日期
            * @param format
            * 格式
            * @return 返回字符型日期
            */
           public static String format(java.util.Date date, String format) {
                       String result = "";
                       try {
                                   if (date != null) {
                                               java.text.DateFormat df = new java.text.SimpleDateFormat(format);
                                               result = df.format(date);
                                   }
                       } catch (Exception e) {
                       }
                       return result;
           }

           public static String format(java.util.Date date) {
                       return format(date, "yyyy/MM/dd");
           }

           /**
            * 返回年份
            *
            * @param date
            * 日期
            * @return 返回年份
            */
           public static int getYear(java.util.Date date) {
                       java.util.Calendar c = java.util.Calendar.getInstance();
                       c.setTime(date);
                       return c.get(java.util.Calendar.YEAR);
           }

           /**
            * 返回月份
            *
            * @param date
            * 日期
            * @return 返回月份
            */
           public static int getMonth(java.util.Date date) {
                       java.util.Calendar c = java.util.Calendar.getInstance();
                       c.setTime(date);
                       return c.get(java.util.Calendar.MONTH) + 1;
           }

           /**
            * 返回日份
            *
            * @param date
            * 日期
            * @return 返回日份
            */
           public static int getDay(java.util.Date date) {
                       java.util.Calendar c = java.util.Calendar.getInstance();
                       c.setTime(date);
                       return c.get(java.util.Calendar.DAY_OF_MONTH);
           }

           /**
            * 返回小时
            *
            * @param date
            * 日期
            * @return 返回小时
            */
           public static int getHour(java.util.Date date) {
                       java.util.Calendar c = java.util.Calendar.getInstance();
                       c.setTime(date);
                       return c.get(java.util.Calendar.HOUR_OF_DAY);
           }

           /**
            * 返回分钟
            *
            * @param date
            * 日期
            * @return 返回分钟
            */
           public static int getMinute(java.util.Date date) {
                       java.util.Calendar c = java.util.Calendar.getInstance();
                       c.setTime(date);
                       return c.get(java.util.Calendar.MINUTE);
           }

           /**
            * 返回秒钟
            *
            * @param date
            * 日期
            * @return 返回秒钟
            */
           public static int getSecond(java.util.Date date) {
                       java.util.Calendar c = java.util.Calendar.getInstance();
                       c.setTime(date);
                       return c.get(java.util.Calendar.SECOND);
           }

           /**
            * 返回毫秒
            *
            * @param date
            * 日期
            * @return 返回毫秒
            */
           public static long getMillis(java.util.Date date) {
                       java.util.Calendar c = java.util.Calendar.getInstance();
                       c.setTime(date);
                       return c.getTimeInMillis();
           }

           /**
            * 返回字符型日期
            *
            * @param date
            * 日期
            * @return 返回字符型日期
            */
           public static String getDate(java.util.Date date) {
                       return format(date, "yyyy/MM/dd");
           }

           /**
            * 返回字符型时间
            *
            * @param date
            * 日期
            * @return 返回字符型时间
            */
           public static String getTime(java.util.Date date) {
                       return format(date, "HH:mm:ss");
           }

           /**
            * 返回字符型日期时间
            *
            * @param date
            * 日期
            * @return 返回字符型日期时间
            */
           public static String getDateTime(java.util.Date date) {
                       return format(date, "yyyy/MM/dd HH:mm:ss");
           }

           /**
            * 日期相加
            *
            * @param date
            * 日期
            * @param day
            * 天数
            * @return 返回相加后的日期
            */
           public static java.util.Date addDate(java.util.Date date, int day) {
                       java.util.Calendar c = java.util.Calendar.getInstance();
                       c.setTimeInMillis(getMillis(date) + ((long) day) * 24 * 3600 * 1000);
                       return c.getTime();
           }

           /**
            * 日期相减
            *
            * @param date
            * 日期
            * @param date1
            * 日期
            * @return 返回相减后的日期
            */
           public static int diffDate(java.util.Date date, java.util.Date date1) {
                       return (int) ((getMillis(date) - getMillis(date1)) / (24 * 3600 * 1000));
           }
}
---------------------------------------------------------------

我来个简单点的,也许有点用

Calendar now = Calendar.getInstance();
int year = now.get(Calendar.YEAR);
int date = now.get(Calendar.DAY_OF_MONTH);
int month = now.get(Calendar.MONTH) + 1;
int hour = now.get(Calendar.HOUR);
int min = now.get(Calendar.MINUTE);
int sec = now.get(Calendar.SECOND);

TNT 2006-07-19 12:15 发表评论

随机数字浮点数字符串产生

TNT — Thu, 01 Jun 2006 02:41:00 GMT

JSP中经常用到随机数字或字符(如密码产生 sessionid产生)可以使用taglib标签产生,本人使用bean产生随机数:

1.可以产生10000000 和 99999999之间随机数

2.可以产生规定数字之间的随机数,如25 100之间

3.可以使用algorithm 和 provider产生一个SecureRandom随机数字或字符串
object instead of a Random object: 71

4.可以产生浮点浮点随机数;

5.可以产生a-zA-Z0-9之间的规定长度个字符串

6.可以产生规定长度的小写字母字符串

7.可以产生任意字符串.

以下jsp bean 在Tomcat Win2000 下调试通过:

/*
*
* 随机数字bean
*/

package mycollect;

import java.util.*;
import java.security.SecureRandom;
import java.security.NoSuchAlgorithmException;
import java.security.NoSuchProviderException;

public class RandomNum {

private Long randomnum = null;
private Float randomfloat = null;
private boolean floatvalue = false;
private long upper = 100;
private long lower = 0;
private String algorithm = null;
private String provider = null;
private boolean secure = false;
private Random random = null;
private SecureRandom secrandom = null;

private final float getFloat() {
if (random == null)
return secrandom.nextFloat();
else
return random.nextFloat();
}

public final void generateRandomObject() throws Exception {

// check to see if the object is a SecureRandom object
if (secure) {
try {
// get an instance of a SecureRandom object
if (provider != null)
// search for algorithm in package provider
secrandom = SecureRandom.getInstance(algorithm, provider);
else
secrandom = SecureRandom.getInstance(algorithm);
} catch (NoSuchAlgorithmException ne) {
throw new Exception(ne.getMessage());
} catch (NoSuchProviderException pe) {
throw new Exception(pe.getMessage());
}
} else
random = new Random();
}

/**
* generate the random number
*
*/
private final void generaterandom() {

int tmprandom = 0; // temp storage for random generated number
Integer rand;

// check to see if float value is expected
if (floatvalue)
randomfloat = new Float(getFloat());
else
randomnum = new Long(lower + (long) ((getFloat() * (upper - lower))));
}

public final Number getRandom() {
generaterandom();
if (floatvalue)
return randomfloat;
else
return randomnum;
}

public final void setRange(long low, long up) {

// set the upper and lower bound of the range
lower = low;
upper = up;

// check to see if a float value is expected
if ((lower == 0) && (upper == 1))
floatvalue = true;
}

/**
* set the algorithm name
*
* @param value name of the algorithm to use for a SecureRandom object
*
*/
public final void setAlgorithm(String value) {
algorithm = value;
secure = true; // a SecureRandom object is to be used
}

public final void setProvider(String value)
{
provider = value;
}

public final void setRange(String value) throws Exception
{
try
{
upper = new Integer(value.substring(value.indexOf('-') + 1)).longValue();
} catch (Exception ex) {
throw new Exception("upper attribute could not be" +
" turned into an Integer default value was used");
}

try
{
lower = new Integer(value.substring(0, value.indexOf('-'))).longValue();
} catch (Exception ex) {
throw new Exception("lower attribute could not be" +
" turned into an Integer default value was used");
}

if ((lower == 0) && (upper == 1))
floatvalue = true;

if (upper < lower)
throw new Exception("You can't have a range where the lowerbound" +
" is higher than the upperbound.");

}

}

//随机字符串bean

package mycollect;

import java.util.*;
import java.security.SecureRandom;
import java.security.NoSuchAlgorithmException;
import java.security.NoSuchProviderException;

public class RandomStrg {

private String randomstr;
private boolean allchars = false;
//欠缺是8位字符串
private Integer length = new Integer(8);
private HashMap hmap;
private ArrayList lower = null;
private ArrayList upper = null;
private char[] single = null;
private int singlecount = 0;
private boolean singles = false;
private String algorithm = null;
private String provider = null;
private boolean secure = false;
private Random random = null;
private SecureRandom secrandom = null;

private final float getFloat() {
if (random == null)
return secrandom.nextFloat();
else
return random.nextFloat();
}

/**
* generate the Random object that will be used for this random number
* generator
*
*/
public final void generateRandomObject() throws Exception {

// check to see if the object is a SecureRandom object
if (secure) {
try {
// get an instance of a SecureRandom object
if (provider != null)
// search for algorithm in package provider
random = SecureRandom.getInstance(algorithm, provider);
else
random = SecureRandom.getInstance(algorithm);
} catch (NoSuchAlgorithmException ne) {
throw new Exception(ne.getMessage());
} catch (NoSuchProviderException pe) {
throw new Exception(pe.getMessage());
}
} else
random = new Random();
}

/**
* generate the random string
*
*/
private final void generaterandom() {

if (allchars)
for (int i = 0; i < length.intValue(); i++)
randomstr = randomstr + new Character((char)((int) 34 +
((int)(getFloat() * 93)))).toString();
else if (singles) {
// check if there are single chars to be included

if (upper.size() == 3) {
// check for the number of ranges max 3 uppercase lowercase digits

// build the random string
for (int i = 0; i < length.intValue(); i++) {
// you have four groups to choose a random number from, to make
// the choice a little more random select a number out of 100

// get a random number even or odd
if (((int) (getFloat() * 100)) % 2 == 0) {

// the number was even get another number even or odd
if (((int) (getFloat() * 100)) % 2 == 0)
// choose a random char from the single char group
randomstr = randomstr + randomSingle().toString();
else
// get a random char from the first range
randomstr = randomstr + randomChar((Character)lower.get(2),
(Character)upper.get(2)).toString();
} else {
// the number was odd

if (((int) (getFloat() * 100)) % 2 == 0)
// choose a random char from the second range
randomstr = randomstr + randomChar((Character)lower.get(1),
(Character)upper.get(1)).toString();
else
// choose a random char from the third range
randomstr = randomstr + randomChar((Character)lower.get(0),
(Character)upper.get(0)).toString();
}
}
} else if (upper.size() == 2) {
// single chars are to be included choose a random char from
// two different ranges

// build the random char from single chars and two ranges
for (int i = 0; i < length.intValue(); i++) {
// select the single chars or a range to get each random char
// from

if (((int)(getFloat() * 100)) % 2 == 0) {

// get random char from the single chars
randomstr = randomstr + randomSingle().toString();
} else if (((int) (getFloat() * 100)) % 2 == 0) {

// get the random char from the first range
randomstr = randomstr + randomChar((Character)lower.get(1),
(Character)upper.get(1)).toString();
} else {

// get the random char from the second range
randomstr = randomstr + randomChar((Character)lower.get(0),
(Character)upper.get(0)).toString();
}
}
} else if (upper.size() == 1) {

// build the random string from single chars and one range
for (int i = 0; i < length.intValue(); i++) {
if (((int) getFloat() * 100) % 2 == 0)
// get a random single char
randomstr = randomstr + randomSingle().toString();
else
// get a random char from the range
randomstr = randomstr + randomChar((Character)lower.get(0),
(Character)upper.get(0)).toString();
}
} else {
// build the rand string from single chars
for (int i = 0; i < length.intValue(); i++)
randomstr = randomstr + randomSingle().toString();
}
} else {

// no single chars are to be included in the random string
if (upper.size() == 3) {

// build random strng from three ranges
for (int i = 0; i < length.intValue(); i++) {

if (((int) (getFloat() * 100)) % 2 == 0) {

// get random char from first range
randomstr = randomstr + randomChar((Character)lower.get(2),
(Character)upper.get(2)).toString();
} else if (((int) (getFloat() * 100)) % 2 == 0) {

// get random char form second range
randomstr = randomstr + randomChar((Character)lower.get(1),
(Character)upper.get(1)).toString();
} else {

// get random char from third range
randomstr = randomstr + randomChar((Character)lower.get(0),
(Character)upper.get(0)).toString();
}
}
} else if (upper.size() == 2) {

// build random string from two ranges
for (int i = 0; i < length.intValue(); i++) {
if (((int) (getFloat() * 100)) % 2 == 0)
// get random char from first range
randomstr = randomstr + randomChar((Character)lower.get(1),
(Character)upper.get(1)).toString();
else
// get random char from second range
randomstr = randomstr + randomChar((Character)lower.get(0),
(Character)upper.get(0)).toString();
}
} else

// build random string
for (int i = 0; i < length.intValue(); i++)
// get random char from only range
randomstr = randomstr + randomChar((Character)lower.get(0),
(Character)upper.get(0)).toString();
}
}

/**
* generate a random char from the single char list
*
* @returns - a randomly selscted character from the single char list
*
*/
private final Character randomSingle() {

return (new Character(single[(int)((getFloat() * singlecount) - 1)]));
}

/**
* generate a random character
*
* @param lower lower bound from which to get a random char
* @param upper upper bound from which to get a random char
*
* @returns - a randomly generated character
*
*/
private final Character randomChar(Character lower, Character upper) {
int tempval;
char low = lower.charValue();
char up = upper.charValue();

// get a random number in the range lowlow - lowup
tempval = (int)((int)low + (getFloat() * ((int)(up - low))));

// return the random char
return (new Character((char) tempval));
}

/**
* get the randomly created string for use with the
* <jsp:getProperty name="id" property="randomstr"/>
*
* @return - randomly created string
*
*/
public final String getRandom() {

randomstr = new String();

generaterandom(); // generate the first random string

if (hmap != null) {

while (hmap.containsKey(randomstr)) {
// random string has already been created generate a different one
generaterandom();
}

hmap.put(randomstr, null); // add the new random string
}

return randomstr;
}

/**
* set the ranges from which to choose the characters for the random string
*
* @param low set of lower ranges
* @param up set of upper ranges
*
*/
public final void setRanges(ArrayList low, ArrayList up) {
lower = low;
upper = up;
}

/**
* set the hashmap that is used to check the uniqueness of random strings
*
* @param map hashmap whose keys are used to insure uniqueness of random strgs
*
*/
public final void setHmap(HashMap map) {
hmap = map;
}

/**
* set the length of the random string
*
* @param value length of the random string
*
*/
public final void setLength(String value) {
length = new Integer(value);

}

/**
* set the provider name
*
* @param value name of the package to check for the algorithm
*
*/
public final void setProvider(String value) {
provider = value;
}

/**
* set the allchars flag
*
* @param value boolean value of the allchars flag
*
*/
public final void setAllchars(boolean value) {
allchars = value;
}

/**
* set the array of single chars to choose from for this random string and the
* number of chars in the array
*
* @param chars the array of single chars
* @param value the number of single chars
*
*/
public final void setSingle(char[] chars, int value) {
single = chars; // set the array of chars
singlecount = value; // set the number of chars in array single
singles = true; // set flag that single chars are in use
}

public final void setCharset(String value)
{
// values tells the method whether or not to check for single chars
boolean more = true;

// create the arraylists to hold the upper and lower bounds for the char
// ranges
lower = new ArrayList(3);
upper = new ArrayList(3);

// user has chosen to use all possible characters in the random string
if (value.compareTo("all") == 0) {
allchars = true; // set allchars flag
// all chars are to be used so there are no single chars to sort
// through
more = false;
}else if ((value.charAt(1) == '-') && (value.charAt(0) != '\\')) {
// run through the ranges at most 3
while (more && (value.charAt(1) == '-')){

// check to make sure that the dash is not the single char
if (value.charAt(0) == '\\')
break;
else {
// add upper and lower ranges to there list
lower.add(new Character(value.charAt(0)));
upper.add(new Character(value.charAt(2)));
}

// check to see if there is more to the charset
if (value.length() <= 3)
more = false;
else
// create a new string so that the next range if there is one
// starts it
value = value.substring(3);
}
}

// if more = false there are no single chars in the charset
if (more) {

single = new char[30]; // create single

// create a set of tokens from the string of single chars
StringTokenizer tokens = new StringTokenizer(value);

while (tokens.hasMoreTokens()) {
// get the next token from the string
String token = tokens.nextToken();

if (token.length() > 1)
// char is a - add it to the list
single[singlecount++] = '-';

// add the current char to the list
single[singlecount++] = token.charAt(0);
}
}
if ((lower == null) && (single == null))
setCharset("a-zA-Z0-9");
}
}

JSP调用语句:

<%@ page contentType="text/html;charset=ISO8859_1" %>
<%@ page import="java.util.*" %>

随机数字浮点数字符串

<%
//Random generator = new Random();
//int limit = 10;
//int randomNumber = (int)(generator.nextDouble() * limit);

out.println("

创建在10000000 和 99999999之间的随机数:");
RNUM.setRange("10000000-99999999");
RNUM.generateRandomObject();
out.println(""+RNUM.getRandom().intValue()+"");

out.println("

在n 25 和 100之间创建一个随机数:");
RNUM.setRange("25-100");
RNUM.generateRandomObject();
out.println(""+RNUM.getRandom().intValue()+"");

Create the same random number between 25 and 100, only use the

algorithm and provider attributes to indicate the use of a SecureRandom

object instead of a Random object:
<%
RNUM.setRange("25-100");
RNUM.setAlgorithm("SHA1PRNG");
RNUM.setProvider("SUN");
RNUM.generateRandomObject();
out.println(""+RNUM.getRandom().intValue()+"");

out.println("

Create a random float value:");
RNUM.setRange("0-1");
RNUM.generateRandomObject();
String radio= new java.text.DecimalFormat("###.##########").format(RNUM.getRandom());
out.println(""+radio+"");

out.println("

===========================================");

out.println("

在a-zA-Z0-9之间,也就是数字和26个字母混合的随机字符串,(欠缺是8位,该功能适合创建随机密码和sessionid)");
RSTR.setCharset("a-zA-Z0-9");
RSTR.generateRandomObject();
out.println(""+RSTR.getRandom()+"");

out.println("

Create a random string 15 lowercase letters long:");
RSTR.setCharset("a-z");
RSTR.setLength("15");
RSTR.generateRandomObject();
out.println(""+RSTR.getRandom()+"");

out.println("

Create a random string with only caps:");
RSTR.setCharset("A-Z");
RSTR.generateRandomObject();
out.println(""+RSTR.getRandom()+"");

out.println("

Create a random string 10 characters long with the charset a-fF-K ! \\ $ % # ^ - * ? notice that the - and had to be escaped with a :");
RSTR.setCharset("a-fF-K!\\$%#^-*?");
RSTR.setLength("10");
RSTR.generateRandomObject();
out.println(""+RSTR.getRandom()+"");

out.println("

Create a random string of all the characters and digits:");
RSTR.setCharset("all");
RSTR.generateRandomObject();
out.println(""+RSTR.getRandom()+" ");

Create the same random string of all the characters and digits, only use

the algorithm and provider attributes to indicate the use of a SecureRandom

object instead of a Random object:
<%
RSTR.setCharset("all");
RSTR.setAlgorithm("SHA1PRNG");
RSTR.setProvider("SUN");
RSTR.generateRandomObject();
out.println(""+RSTR.getRandom()+"");

TNT 2006-06-01 10:41 发表评论

BASE64编码与解码

TNT — Thu, 01 Jun 2006 02:40:00 GMT

/**
    * Encode a string using Base64 encoding. Used when storing passwords
    * as cookies.
    *
    * This is weak encoding in that anyone can use the decodeString
    * routine to reverse the encoding.
    *
    * @param str
    * @return String
    */
   public static String encodeString(String str) {
       sun.misc.BASE64Encoder encoder = new sun.misc.BASE64Encoder();
       return encoder.encodeBuffer(str.getBytes()).trim();
   }

   /**
    * Decode a string using Base64 encoding.
    *
    * @param str
    * @return String
    */
   public static String decodeString(String str) {
       sun.misc.BASE64Decoder dec = new sun.misc.BASE64Decoder();
       try {
           return new String(dec.decodeBuffer(str));
       } catch (IOException io) {
               throw new RuntimeException(io.getMessage(), io.getCause());
       }
    }

TNT 2006-06-01 10:40 发表评论

JAVA对文件的操作

TNT — Thu, 01 Jun 2006 02:39:00 GMT

import java.io.*;

public class FileOperate {
public FileOperate() {
}

/**
   * 新建目录
   * @param folderPath String 如 c:/fqf
   * @return boolean
   */
public void newFolder(String folderPath) {
    try {
      String filePath = folderPath;
      filePath = filePath.toString();
      java.io.File myFilePath = new java.io.File(filePath);
      if (!myFilePath.exists()) {
        myFilePath.mkdir();
      }
    }
    catch (Exception e) {
      System.out.println("新建目录操作出错");
      e.printStackTrace();
    }
}

/**
   * 新建文件
   * @param filePathAndName String 文件路径及名称如c:/fqf.txt
   * @param fileContent String 文件内容
   * @return boolean
   */
public void newFile(String filePathAndName, String fileContent) {

    try {
      String filePath = filePathAndName;
      filePath = filePath.toString();
      File myFilePath = new File(filePath);
      if (!myFilePath.exists()) {
        myFilePath.createNewFile();
      }
      FileWriter resultFile = new FileWriter(myFilePath);
      PrintWriter myFile = new PrintWriter(resultFile);
      String strContent = fileContent;
      myFile.println(strContent);
      resultFile.close();

    }
    catch (Exception e) {
      System.out.println("新建目录操作出错");
      e.printStackTrace();

}

/**
   * 删除文件
   * @param filePathAndName String 文件路径及名称如c:/fqf.txt
   * @param fileContent String
   * @return boolean
   */
public void delFile(String filePathAndName) {
    try {
      String filePath = filePathAndName;
      filePath = filePath.toString();
      java.io.File myDelFile = new java.io.File(filePath);
      myDelFile.delete();

    }
    catch (Exception e) {
      System.out.println("删除文件操作出错");
      e.printStackTrace();

}

/**
   * 删除文件夹
   * @param filePathAndName String 文件夹路径及名称如c:/fqf
   * @param fileContent String
   * @return boolean
   */
public void delFolder(String folderPath) {
    try {
      delAllFile(folderPath); //删除完里面所有内容
      String filePath = folderPath;
      filePath = filePath.toString();
      java.io.File myFilePath = new java.io.File(filePath);
      myFilePath.delete(); //删除空文件夹

    }
    catch (Exception e) {
      System.out.println("删除文件夹操作出错");
      e.printStackTrace();

}

/**
   * 删除文件夹里面的所有文件
   * @param path String 文件夹路径如 c:/fqf
   */
public void delAllFile(String path) {
    File file = new File(path);
    if (!file.exists()) {
      return;
    }
    if (!file.isDirectory()) {
      return;
    }
    String[] tempList = file.list();
    File temp = null;
    for (int i = 0; i < tempList.length; i++) {
      if (path.endsWith(File.separator)) {
        temp = new File(path + tempList[i]);
      }
      else {
        temp = new File(path + File.separator + tempList[i]);
      }
      if (temp.isFile()) {
        temp.delete();
      }
      if (temp.isDirectory()) {
        delAllFile(path+"/"+ tempList[i]);//先删除文件夹里面的文件
        delFolder(path+"/"+ tempList[i]);//再删除空文件夹
      }
    }
}

/**
   * 复制单个文件
   * @param oldPath String 原文件路径如：c:/fqf.txt
   * @param newPath String 复制后路径如：f:/fqf.txt
   * @return boolean
   */
public void copyFile(String oldPath, String newPath) {
    try {
      int bytesum = 0;
      int byteread = 0;
      File oldfile = new File(oldPath);
      if (oldfile.exists()) { //文件存在时
        InputStream inStream = new FileInputStream(oldPath); //读入原文件
        FileOutputStream fs = new FileOutputStream(newPath);
        byte[] buffer = new byte[1444];
        int length;
        while ( (byteread = inStream.read(buffer)) != -1) {
          bytesum += byteread; //字节数文件大小
          System.out.println(bytesum);
          fs.write(buffer, 0, byteread);
        }
        inStream.close();
      }
    }
    catch (Exception e) {
      System.out.println("复制单个文件操作出错");
      e.printStackTrace();

}

/**
   * 复制整个文件夹内容
   * @param oldPath String 原文件路径如：c:/fqf
   * @param newPath String 复制后路径如：f:/fqf/ff
   * @return boolean
   */
public void copyFolder(String oldPath, String newPath) {

    try {
      (new File(newPath)).mkdirs(); //如果文件夹不存在则建立新文件夹
      File a=new File(oldPath);
      String[] file=a.list();
      File temp=null;
      for (int i = 0; i < file.length; i++) {
        if(oldPath.endsWith(File.separator)){
          temp=new File(oldPath+file[i]);
        }
        else{
          temp=new File(oldPath+File.separator+file[i]);
        }

        if(temp.isFile()){
          FileInputStream input = new FileInputStream(temp);
          FileOutputStream output = new FileOutputStream(newPath + "/" +
              (temp.getName()).toString());
          byte[] b = new byte[1024 * 5];
          int len;
          while ( (len = input.read(b)) != -1) {
            output.write(b, 0, len);
          }
          output.flush();
          output.close();
          input.close();
        }
        if(temp.isDirectory()){//如果是子文件夹
          copyFolder(oldPath+"/"+file[i],newPath+"/"+file[i]);
        }
      }
    }
    catch (Exception e) {
      System.out.println("复制整个文件夹内容操作出错");
      e.printStackTrace();

}

/**
   * 移动文件到指定目录
   * @param oldPath String 如：c:/fqf.txt
   * @param newPath String 如：d:/fqf.txt
   */
public void moveFile(String oldPath, String newPath) {
    copyFile(oldPath, newPath);
    delFile(oldPath);

}

/**
   * 移动文件到指定目录
   * @param oldPath String 如：c:/fqf.txt
   * @param newPath String 如：d:/fqf.txt
   */
public void moveFolder(String oldPath, String newPath) {
    copyFolder(oldPath, newPath);
    delFolder(oldPath);

}
}

TNT 2006-06-01 10:39 发表评论

Java.Math API

TNT — Thu, 01 Jun 2006 02:38:00 GMT

Math.PI 记录的圆周率
Math.E 记录e的常量
Math中还有一些类似的常量，都是一些工程数学常用量。

Math.abs 求绝对值
Math.sin 正弦函数 Math.asin 反正弦函数
Math.cos 余弦函数 Math.acos 反余弦函数
Math.tan 正切函数 Math.atan 反正切函数 Math.atan2 商的反正切函数
Math.toDegrees 弧度转化为角度 Math.toRadians 角度转化为弧度
Math.ceil 得到不小于某数的最大整数
Math.floor 得到不大于某数的最大整数
Math.IEEEremainder 求余
Math.max 求两数中最大
Math.min 求两数中最小
Math.sqrt 求开方
Math.pow 求某数的任意次方, 抛出ArithmeticException处理溢出异常
Math.exp 求e的任意次方
Math.log10 以10为底的对数
Math.log 自然对数
Math.rint 求距离某数最近的整数（可能比某数大，也可能比它小）
Math.round 同上，返回int型或者long型（上一个函数返回double型）
Math.random 返回0，1之间的一个随机数

TNT 2006-06-01 10:38 发表评论

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