BlogJava-vjame-随笔分类-Java App

MyEclipse Subscription code生成器代码

lanjh — Wed, 12 Oct 2011 01:02:00 GMT

对应不同的版本把KeyGenerator类放到任意工程下，执行程序，在控制台输入注册名称，回车后会生成序列号。

package com.strongit.test;

import java.io.*;

/**
*  MyEclipse6.0 Register Code
* @author lanjh
*
*/
public class KeyGeneratorForMyEclipse6 {

     private static final String LL = "Decompiling this copyrighted software is a violation of both your license agreement and the Digital Millenium Copyright Act of 1998 (http://www.loc.gov/copyright/legislation/dmca.pdf). Under section 1204 of the DMCA, penalties range up to a $500,000 fine or up to five years imprisonment for a first offense. Think about it; pay for a license, avoid prosecution, and feel better about yourself.";

        public String getSerial(String userId, String licenseNum) {

            java.util.Calendar cal = java.util.Calendar.getInstance();

            cal.add(1, 3);

            cal.add(6, -1);

            java.text.NumberFormat nf = new java.text.DecimalFormat("000");

            licenseNum = nf.format(Integer.valueOf(licenseNum));

            String verTime = new StringBuilder("-").append(new java.text.

                    SimpleDateFormat("yyMMdd").format(cal.getTime())).append("0").

                             toString();

            String type = "YE3MP-";

            String need = new StringBuilder(userId.substring(0, 1)).append(type).

                          append("300").append(licenseNum).append(verTime).toString();

            String dx = new StringBuilder(need).append(LL).append(userId).toString();

            int suf = this.decode(dx);

            String code = new StringBuilder(need).append(String.valueOf(suf)).

                          toString();

            return this.change(code);

        }

        private int decode(String s) {

            int i;

            char[] ac;

            int j;

            int k;

            i = 0;

            ac = s.toCharArray();

            j = 0;

            k = ac.length;

            while (j < k) {

                i = (31 * i) + ac[j];

                j++;

            }

            return Math.abs(i);

        }

        private String change(String s) {

            byte[] abyte0;

            char[] ac;

            int i;

            int k;

            int j;

            abyte0 = s.getBytes();

            ac = new char[s.length()];

            i = 0;

            k = abyte0.length;

            while (i < k) {

                j = abyte0[i];

                if ((j >= 48) && (j <= 57)) {

                    j = (((j - 48) + 5) % 10) + 48;

                } else if ((j >= 65) && (j <= 90)) {

                    j = (((j - 65) + 13) % 26) + 65;

                } else if ((j >= 97) && (j <= 122)) {

                    j = (((j - 97) + 13) % 26) + 97;

                }

                ac[i] = (char) j;

                i++;

            }

            return String.valueOf(ac);

        }

        public KeyGeneratorForMyEclipse6() {

            super();

        }

        public static void main(String[] args) {

            try {

                System.out.println("please input register name:");

                BufferedReader reader = new BufferedReader(new InputStreamReader(

                        System.in));

                String userId = null;

                userId = reader.readLine();

                KeyGeneratorForMyEclipse6 myeclipsegen = new KeyGeneratorForMyEclipse6();

                String res = myeclipsegen.getSerial(userId, "20");

                System.out.println("Serial:" + res);

                reader.readLine();

            } catch (IOException ex) {

            }

        }
}

package com.strongit.test;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

/**
* MyEclipse7.0 Register Code
* @author lanjh
*
*/
public class KeyGeneratorForMyEclipse7 {

    private static final String LL = "Decompiling this copyrighted software is a violation of both your license agreement and the Digital Millenium Copyright Act of 1998 (http://www.loc.gov/copyright/legislation/dmca.pdf). Under section 1204 of the DMCA, penalties range up to a $500,000 fine or up to five years imprisonment for a first offense. Think about it; pay for a license, avoid prosecution, and feel better about yourself.";

    public String getSerial(String userId, String licenseNum) {

        java.util.Calendar cal = java.util.Calendar.getInstance();

        cal.add(1, 3);

        cal.add(6, -1);

        java.text.NumberFormat nf = new java.text.DecimalFormat("000");

        licenseNum = nf.format(Integer.valueOf(licenseNum));

        String verTime = new StringBuilder("-").append(

        new java.text.SimpleDateFormat("yyMMdd").format(cal.getTime()))

        .append("0").toString();

        String type = "YE3MP-";

        String need = new StringBuilder(userId.substring(0, 1)).append(type)

        .append("300").append(licenseNum).append(verTime).toString();

        String dx = new StringBuilder(need).append(LL).append(userId)

        .toString();

        int suf = this.decode(dx);

        String code = new StringBuilder(need).append(String.valueOf(suf))

        .toString();

        return this.change(code);

    }

    private int decode(String s) {

        int i;

        char[] ac;

        int j;

        int k;

        i = 0;

        ac = s.toCharArray();

        j = 0;

        k = ac.length;

        while (j < k) {

            i = (31 * i) + ac[j];

            j++;

        }

        return Math.abs(i);

    }

    private String change(String s) {

        byte[] abyte0;

        char[] ac;

        int i;

        int k;

        int j;

        abyte0 = s.getBytes();

        ac = new char[s.length()];

        i = 0;

        k = abyte0.length;

        while (i < k) {

            j = abyte0[i];

            if ((j >= 48) && (j <= 57)) {

                j = (((j - 48) + 5) % 10) + 48;

            } else if ((j >= 65) && (j <= 90)) {

                j = (((j - 65) + 13) % 26) + 65;

            } else if ((j >= 97) && (j <= 122)) {

                j = (((j - 97) + 13) % 26) + 97;

            }

            ac[i] = (char) j;

            i++;

        }

        return String.valueOf(ac);

    }

    public KeyGeneratorForMyEclipse7() {

        super();

    }

    public static void main(String[] args) {

        try {

            System.out.println("please input register name:");

            BufferedReader reader = new BufferedReader(new InputStreamReader(

            System.in));

            String userId = null;

            userId = reader.readLine();

            KeyGeneratorForMyEclipse7 myeclipsegen = new KeyGeneratorForMyEclipse7();

            String res = myeclipsegen.getSerial(userId, "5");

            System.out.println("Serial:" + res);

            reader.readLine();

        } catch (IOException ex) {

        }

    }

}

lanjh 2011-10-12 09:02 发表评论

使用greenmail测试发送邮件

lanjh — Sun, 14 Aug 2011 03:15:00 GMT

1、自定义异常类AccountEmailException

public class AccountEmailException
    extends Exception
{
    private static final long serialVersionUID = -4817386460334501672L;

    public AccountEmailException( String message )
    {
        super( message );
    }

    public AccountEmailException( String message, Throwable throwable )
    {
        super( message, throwable );
    }
}

2、发邮件的接口类

public interface AccountEmailService
{
    /**
     *         发送邮件
     *          to为接收地址，subject为邮件主题，htmlText为邮件内容
      *   @author lanjh 上午10:51:45
      *   @return void
      *   @throws  抛出异常说明
     */
    void sendMail( String to, String subject, String htmlText )
        throws AccountEmailException;
}

3、接口实现类

public class AccountEmailServiceImpl
    implements AccountEmailService
{
    //spring framework中帮助邮件发送工具类
    private JavaMailSender javaMailSender;

    private String systemEmail;

    public void sendMail( String to, String subject, String htmlText )
        throws AccountEmailException
    {
        try
        {
            //msg对应着将要发送的邮件
            MimeMessage msg = javaMailSender.createMimeMessage();
            //帮助设置邮件msg相关信息
            MimeMessageHelper msgHelper = new MimeMessageHelper( msg );
            //systemEmail 系统邮箱设置
            msgHelper.setFrom( systemEmail );
            msgHelper.setTo( to );
            msgHelper.setSubject( subject );
            //true表示邮件内容为html格式
            msgHelper.setText( htmlText, true );

            javaMailSender.send( msg );
        }
        catch ( MessagingException e )
        {
            throw new AccountEmailException( "Faild to send mail.", e );
        }
    }

    public JavaMailSender getJavaMailSender()
    {
        return javaMailSender;
    }

    public void setJavaMailSender( JavaMailSender javaMailSender )
    {
        this.javaMailSender = javaMailSender;
    }

    public String getSystemEmail()
    {
        return systemEmail;
    }

    public void setSystemEmail( String systemEmail )
    {
        this.systemEmail = systemEmail;
    }
}

4、测试类

public class AccountEmailServiceTest
{
    private GreenMail greenMail;

    @Before
    public void startMailServer()
        throws Exception
    {
        greenMail = new GreenMail( ServerSetup.SMTP );
        greenMail.setUser( "lanjh", "******" );
        greenMail.start();
    }

    @Test
    public void testSendMail()
        throws Exception
    {
        ApplicationContext ctx = new ClassPathXmlApplicationContext( "account-email.xml" );
        AccountEmailService accountEmailService = (AccountEmailService) ctx.getBean( "accountEmailService" );

        String subject = "Test Subject";
        String htmlText = "

Test

";
        accountEmailService.sendMail( "275581963@qq.com", subject, htmlText );

        greenMail.waitForIncomingEmail( 2000, 1 );

        Message[] msgs = greenMail.getReceivedMessages();
        assertEquals( 1, msgs.length );
        assertEquals( "lanjh@chinalmtc.com", msgs[0].getFrom()[0].toString() );
        assertEquals( subject, msgs[0].getSubject() );
        assertEquals( htmlText, GreenMailUtil.getBody( msgs[0] ).trim() );
    }

    @After
    public void stopMailServer()
        throws Exception
    {
        greenMail.stop();
    }
}

5、相关配置文件

account-mail.xml

xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-2.5.xsd">

    <bean id="propertyConfigurer"
        class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
        <property name="location" value="classpath:account-service.properties" />
    bean>

    <bean id="javaMailSender" class="org.springframework.mail.javamail.JavaMailSenderImpl">
        <property name="protocol" value="${email.protocol}" />
        <property name="host" value="${email.host}" />
        <property name="port" value="${email.port}" />
        <property name="username" value="${email.username}" />
        <property name="password" value="${email.password}" />
        <property name="javaMailProperties">
            <props>
                <prop key="mail.${email.protocol}.auth">${email.auth}prop>
            props>
        property>
    bean>

    <bean id="accountEmailService"
        class="com.juvenxu.mvnbook.account.email.AccountEmailServiceImpl">
        <property name="javaMailSender" ref="javaMailSender" />
        <property name="systemEmail" value="${email.systemEmail}" />
    bean>
beans>

account-service.properties

email.protocol=smtp
email.host=localhost
email.port=25
email.username=lanjh
email.password=*****
email.auth=true
email.systemEmail=lanjh@chinalmtc.com

greenmail api参考
http://www.icegreen.com/greenmail/javadocs/overview-summary.html

lanjh 2011-08-14 11:15 发表评论

NetUtil 网络服务器端口辅助类

lanjh — Tue, 28 Jul 2009 09:01:00 GMT

package com.strongit.emp.common.utils;

import java.io.IOException;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.net.Socket;
import java.net.UnknownHostException;

//TODO doc
public class NetUtil {

    public static boolean telnetStringPort(String ip, String port, int timeout) {
        if (port == null || !isValidPort(port)) {
            return NetUtil.ping(ip, timeout);
        }

        return NetUtil.telnet(ip, Integer.valueOf(port.trim()).intValue(),
                timeout);
    }

    public static boolean ping(String ip, int timeout) {
        AssertUtil.assertNull("IP is null.", ip);

        try {
            return InetAddress.getByName(ip.trim()).isReachable(timeout);
        } catch (UnknownHostException e) {
            System.err.println("UnknownHostException:" + e.getMessage());
            return false;
        } catch (IOException e) {
            System.err.println("IOException:" + e.getMessage());
            return false;
        }
    }

    public static boolean telnet(String ip, int port, int timeout) {
        AssertUtil.assertNull("IP is null.", ip);

        Socket server = null;
        try {
            server = new Socket();
            server.connect(new InetSocketAddress(ip.trim(), port), timeout);
            return true;
        } catch (UnknownHostException e) {
            System.err.println("UnknownHostException:" + e.getMessage());
            return false;
        } catch (IOException e) {
            System.err.println("IOException:" + e.getMessage());
            return false;
        } finally {
            if (server != null)
                try {
                    server.close();
                } catch (IOException e) {

                }
        }
    }

    public static boolean isValidPort(String port) {
        if (port != null && port.trim().matches("^[1-9][0-9]{0,3}$|^[1-5][0-9]{0,4}$|^6[0-5]{2}[0-3][0-5]$")) {
            int portInt = Integer.valueOf(port.trim()).intValue();
            if(portInt > 0 && portInt <= 0xFFFF) return true;
        }

        return false;
    }

    public static void main(String arg[]){
        boolean b = telnetStringPort("192.168.50.181","10242",1);

        System.out.println(b);
    }
}

lanjh 2009-07-28 17:01 发表评论

从网页中提取电子邮箱地址

lanjh — Mon, 09 Feb 2009 05:25:00 GMT

import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class EmailSpider {

    public static void main(String[] args) {
        try {
            BufferedReader br = new BufferedReader(new FileReader("D:\\share\\courseware\\1043633.html"));
            String line = "";
            while((line=br.readLine()) != null) {
                parse(line);
            }
        } catch (FileNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

    private static void parse(String line) {
        Pattern p = Pattern.compile("[\\w[.-]]+@[\\w[.-]]+\\.[\\w]+");
        Matcher m = p.matcher(line);
        while(m.find()) {
            System.out.println(m.group());
        }
    }

}

lanjh 2009-02-09 13:25 发表评论

代码统计

lanjh — Mon, 09 Feb 2009 05:23:00 GMT

import java.io.BufferedReader;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;

public class CodeCounter {

    static long normalLines = 0;
    static long commentLines = 0;
    static long whiteLines = 0;

    public static void main(String[] args) {
        File f = new File("D:\\share\\JavaProjects\\TankWar1.9.11\\src");
        File[] codeFiles = f.listFiles();
        for(File child : codeFiles){
            if(child.getName().matches(".*\\.java$")) {
                parse(child);
            }
        }

        System.out.println("normalLines:" + normalLines);
        System.out.println("commentLines:" + commentLines);
        System.out.println("whiteLines:" + whiteLines);

    }

    private static void parse(File f) {
        BufferedReader br = null;
        boolean comment = false;
        try {
            br = new BufferedReader(new FileReader(f));
            String line = "";
            while((line = br.readLine()) != null) {
                line = line.trim();
                if(line.matches("^[\\s&&[^\\n]]*$")) {
                    whiteLines ++;
                } else if (line.startsWith("/*") && !line.endsWith("*/")) {
                    commentLines ++;
                    comment = true;
                } else if (line.startsWith("/*") && line.endsWith("*/")) {
                    commentLines ++;
                } else if (true == comment) {
                    commentLines ++;
                    if(line.endsWith("*/")) {
                        comment = false;
                    }
                } else if (line.startsWith("//")) {
                    commentLines ++;
                } else {
                    normalLines ++;
                }
            }
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if(br != null) {
                try {
                    br.close();
                    br = null;
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }

}

lanjh 2009-02-09 13:23 发表评论

使用Java Service Wrapper工具把Java程序提升为Windows系统服务

lanjh — Mon, 12 Jan 2009 02:46:00 GMT

在使用之前需下载Java Service Wrapper的发布包

http://sourceforge.net/project/showfiles.php?group_id=39428

下面简单介绍一下具体的使用步骤：

1.  将下载的Java Service Wrapper包解压到本地，目录为{WRAPPER_HOME}；
2.  服务应用程序名为MyServApp，在目录d:"MyServApp下建立bin、conf、logs、lib目录；并把你的已有应用程序如NioBlockingServer.class拷贝到该目录下；
3.  将{WRAPPER_HOME}"src"bin"下的遗以下文件拷贝到MyServApp目录下，并重命名。
{WRAPPER_HOME}"bin"Wrapper.exe C:" MyServApp "bin"Wrapper.exeà
C:"à{WRAPPER_HOME}"src"bin"App.bat.in MyServApp"bin"MyApp.bat
C:"à{WRAPPER_HOME}"src"bin"InstallApp-NT.bat.in MyServApp"bin"InstallMyApp-NT.bat
{WRAPPER_HOME}"src"bin"UninstallApp-NT.bat.in C:" MyServApp"bin"UninstallMyApp-NT.batà
4.  将{WRAPPER_HOME}"lib下的以下文件拷贝到C:" MyServApp "lib目录下
{WRAPPER_HOME}"lib"Wrapper.DLL
{WRAPPER_HOME}"lib"wrapper.jar
5.  将{WRAPPER_HOME}"src"conf"wrapper.conf.in拷贝到C:" MyServApp "conf目录下并命名为wrapper.conf；并修改wrapper.conf文件，在其中配置您的应用服务。
主要修改以下几项即可：
#你的JVM位置：
wrapper.java.command=D:"Sun"j2sdk1.4.0_03"bin"java
#运行参数：如：
wrapper.java.additional.1=-Dprogram.name=run.bat
#classpath：
wrapper.java.classpath.1=../lib/wrapper.jar
wrapper.java.classpath.2=../bin/.
# Java Library Path (location of Wrapper.DLL or libwrapper.so)
wrapper.java.library.path.1=../lib
#MAIN CLASS 此处决定了使用Java Service Wrapper的方式
wrapper.java.mainclass=org.tanukisoftware.wrapper.WrapperSimpleApp
#你的Java应用类
wrapper.app.parameter.1= NonBlockingServer
# 服务名
wrapper.ntservice.name=NB

# Display name of the service
wrapper.ntservice.displayname=Nio Nonblocking Server
# 服务描述
wrapper.ntservice.description=Nio Nonblocking Server
其他的配置根据你的需要改变即可
6.  对以上配置的MyApp.bat进行测试，运行MyApp.bat，就像在Console窗口下运行Tomcat一样；
7.  对以上配置的服务进行测试，运行C:" MyServApp"bin"InstallMyApp-NT.bat将把你的应用（此处为NioBlockingServer）安装到Win32系统服务中了。
8.  打开控制面板－管理程序－服务，看到Nio Nonblocking Server已经在系统服务中了，其他用法就与我们熟悉的Windows服务一样了。

把JAVA程序部署为Windows Service需要修改的操作

1.把JAVA程序所用到的Class拷到bin目录下;所有jar考到lib目录

2.修改config/wrapper.conf 文件

1)修改JDK安装路径 :wrapper.java.command=C:"jdk1.5.0"bin"java

2)修改classpath:wrapper.java.classpath.2=../bin/.

3)修改要启动的JAVA类:wrapper.app.parameter.1= HelloWorld

4)修改服务名称:wrapper.ntservice.name=MyJavaService

5)修改"服务"里显示的名称:wrapper.ntservice.displayname=MyJavaService

6)服务说明:wrapper.ntservice.description=MyJavaService Test

bin/StartApp.bat 为控制台方式运行程序

bin/InstallApp-NT.bat 安装服务

bin/UninstallApp-NT.bat 删除服务

把项目中的接收程序提升为系统服务

config/wrapper.conf 文件

#********************************************************************

# Wrapper Properties

#********************************************************************

# Java Application

wrapper.java.command=java

# Java Main class. This class must implement the WrapperListener interface

# or guarantee that the WrapperManager class is initialized. Helper

# classes are provided to do this for you. See the Integration section

# of the documentation for details.

wrapper.java.mainclass=org.tanukisoftware.wrapper.WrapperSimpleApp

# Java Classpath (include wrapper.jar) Add class path elements as

# needed starting from 1

wrapper.java.classpath.1=../lib/wrapper.jar

wrapper.java.classpath.2=../lib/wrappertest.jar

wrapper.java.classpath.3=../bin/.

wrapper.java.classpath.4=../lib/jaxen-1.1-beta-7.jar

wrapper.java.classpath.5=../lib/tlclient.jar

wrapper.java.classpath.6=../lib/tlqadapter.jar

wrapper.java.classpath.7=../lib/tlqconf.jar

wrapper.java.classpath.8=../lib/TlqMng.jar

wrapper.java.classpath.9=../lib/weblogic.jar

wrapper.java.classpath.10=../lib/jms.jar

wrapper.java.classpath.11=../lib/log4j-1.2.8.jar

wrapper.java.classpath.12=../lib/swt.jar

wrapper.java.classpath.13=../lib/javax.jms.jar

wrapper.java.classpath.14=../lib/jaxrpc.jar

wrapper.java.classpath.15=../lib/commons-discovery-0.2.jar

wrapper.java.classpath.16=../lib/commons-logging-1.0.4.jar

wrapper.java.classpath.17=../lib/dom4j-1.6.1.jar

# Java Library Path (location of Wrapper.DLL or libwrapper.so)

wrapper.java.library.path.1=../lib

# Java Additional Parameters

#wrapper.java.additional.1= -Dprogram.name=StartApp.bat

# Initial Java Heap Size (in MB)

#wrapper.java.initmemory=3

# Maximum Java Heap Size (in MB)

#wrapper.java.maxmemory=64

# Application parameters. Add parameters as needed starting from 1

wrapper.app.parameter.1= MainTest

#********************************************************************

# Wrapper Logging Properties

#********************************************************************

# Format of output for the console. (See docs for formats)

wrapper.console.format=PM

# Log Level for console output. (See docs for log levels)

wrapper.console.loglevel=INFO

# Log file to use for wrapper output logging.

wrapper.logfile=../logs/log.log

# Format of output for the log file. (See docs for formats)

wrapper.logfile.format=LPTM

# Log Level for log file output. (See docs for log levels)

wrapper.logfile.loglevel=INFO

# Maximum size that the log file will be allowed to grow to before

# the log is rolled. Size is specified in bytes. The default value

# of 0, disables log rolling. May abbreviate with the 'k' (kb) or

# 'm' (mb) suffix. For example: 10m = 10 megabytes.

wrapper.logfile.maxsize=0

# Maximum number of rolled log files which will be allowed before old

# files are deleted. The default value of 0 implies no limit.

wrapper.logfile.maxfiles=0

# Log Level for sys/event log output. (See docs for log levels)

wrapper.syslog.loglevel=NONE

#********************************************************************

# Wrapper Windows Properties

#********************************************************************

# Title to use when running as a console

wrapper.console.title=MyJavaService

#********************************************************************

# Wrapper Windows NT/2000/XP Service Properties

#********************************************************************

# WARNING - Do not modify any of these properties when an application

# using this configuration file has been installed as a service.

# Please uninstall the service before modifying this section. The

# service can then be reinstalled.

# Name of the service

wrapper.ntservice.name=MyJavaService

# Display name of the service

wrapper.ntservice.displayname=MyJavaService

# Description of the service

wrapper.ntservice.description=MyJavaService Test

# Service dependencies. Add dependencies as needed starting from 1

wrapper.ntservice.dependency.1=

# Mode in which the service is installed. AUTO_START or DEMAND_START

wrapper.ntservice.starttype=AUTO_START

# Allow the service to interact with the desktop.

wrapper.ntservice.interactive=false

采用这种方式，即可简单有效的把我们的服务程序包装成为系统服务程序，并增强了日志功能，我们可以把MyServApp的几个文件做成模板，每次修改文件名，配置文件就可以了，还可以做成Eclipse的plugin，鼠标点点就把应用配成服务了。

lanjh 2009-01-12 10:46 发表评论

SWT Table的Tableitem多行显示

lanjh — Sat, 10 Jan 2009 01:40:00 GMT

1：Table创建好之后添加如下代码：

        Listener paintListener = new Listener() {
            public void handleEvent(Event event) {
                switch(event.type) {
                    case SWT.MeasureItem: {
                        TableItem item = (TableItem)event.item;
                        String text = getText(item, event.index);
                        Point size = event.gc.textExtent(text);
                        event.width = size.x;
                        event.height = Math.max(event.height, size.y);
                        break;
                    }
                    case SWT.PaintItem: {
                        TableItem item = (TableItem)event.item;
                        String text = getText(item, event.index);
                        Point size = event.gc.textExtent(text);
                        int offset2 = event.index == 0 ? Math.max(0, (event.height - size.y) / 2) : 0;
                        event.gc.drawText(text, event.x, event.y + offset2, true);
                        break;
                    }
                    case SWT.EraseItem: {
                        event.detail &= ~SWT.FOREGROUND;
                        break;
                    }
                }
            }
            String getText(TableItem item, int column) {
                return item.getText(column);
            }
        };
       table.addListener(SWT.MeasureItem, paintListener);
       table.addListener(SWT.PaintItem, paintListener);
       table.addListener(SWT.EraseItem, paintListener);

2. 换行要自己加个“\n”到字符串中，如

TableItem item = new TableItem(table, SWT.NONE, table.getItemCount());
item.setText("first line" + "\n" + "second line");

3.如图所示

lanjh 2009-01-10 09:40 发表评论

Cron 触发器

lanjh — Mon, 22 Dec 2008 13:28:00 GMT

摘要: 一个cron表达式有至少6个（也可能是7个）由空格分隔的时间元素。从左至右，这些元素的定义如下： 1．秒（0–59） 2．分钟（0–59） 3．小时（0–23） 4．月份中的日期（1–31） 5．月份（1–12或JAN–DEC） 6．星期中的日期（1–7或SUN–SAT） 7．年份（197... 阅读全文

lanjh 2008-12-22 21:28 发表评论

高性能锁ReentrantReadWriteLock

lanjh — Mon, 22 Dec 2008 06:57:00 GMT

多线程读取并修改一个资源时，通常使用synchronized同步锁。性能损失情况很严重。jdk5.0以后提供了新的ReentrantReadWriteLock可以提供比synchronized更高性能的并发。

Dictionary.java

package com.test;

import java.util.HashMap;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantReadWriteLock;

public class Dictionary {

    private final ReentrantReadWriteLock readWriteLock = new ReentrantReadWriteLock();

    private final Lock read = readWriteLock.readLock();

    private final Lock write = readWriteLock.writeLock();

    private HashMap<String, String> dictionary = new HashMap<String, String>();

    public void set(String key, String value) {
        write.lock();
        try {
            dictionary.put(key, value);
        } finally {
            write.unlock();
        }
    }

    public String get(String key) {
        read.lock();
        try {
            return dictionary.get(key);
        } finally {
            read.unlock();
        }
    }

    public String[] getKeys() {
        read.lock();
        try {
            String keys[] = new String[dictionary.size()];
            return dictionary.keySet().toArray(keys);
        } finally {
            read.unlock();
        }
    }

    public static void main(String[] args) {
        Dictionary dictionary = new Dictionary();
        dictionary.set("java", "object oriented");
        dictionary.set("linux", "rulez");
        //dictionary.set("C++", "lanjh");
        Writer writer = new Writer(dictionary, "Mr. Writer ");
        //Writer writer2 = new Writer(dictionary, "Mr. Writer 2");
        Reader reader1 = new Reader(dictionary, "Mrs Reader 1");
        Reader reader2 = new Reader(dictionary, "Mrs Reader 2");
        Reader reader3 = new Reader(dictionary, "Mrs Reader 3");
        Reader reader4 = new Reader(dictionary, "Mrs Reader 4");
        Reader reader5 = new Reader(dictionary, "Mrs Reader 5");
        writer.start();
        //writer2.start();
        reader1.start();
        reader2.start();
        reader3.start();
        reader4.start();
        reader5.start();
    }
}

Reader.java

package com.test;

public class Reader extends Thread{

       private Dictionary dictionary = null;
       public Reader(Dictionary d, String threadName) {
         this.dictionary = d;
         this.setName(threadName);
       }

       private boolean runForestRun = true;

       public void run() {
         while (runForestRun) {
           String [] keys = dictionary.getKeys();
           for (String key : keys) {
             //reading from dictionary with READ LOCK
             String value = dictionary.get(key);

             //make what ever you want with the value.
             System.out.println(this.getName()+" = "+key + " : " + value);
           }

           //update every seconds
           try {
             Thread.sleep(1000);
           } catch (InterruptedException e) {
             e.printStackTrace();
           }
         }
       }

       public void stopReader(){
         this.runForestRun = false;
         this.interrupt();
       }
     }

Writer.java

package com.test;

public class Writer extends Thread{
       private boolean runForestRun = true;
       private Dictionary dictionary = null;

       public Writer(Dictionary d, String threadName) {
         this.dictionary = d;
         this.setName(threadName);
       }
       @Override
       public void run() {
         while (this.runForestRun) {
           String [] keys = dictionary.getKeys();
           for (String key : keys) {
             String newValue = getNewValueFromDatastore(key);
             //updating dictionary with WRITE LOCK
             dictionary.set(key, newValue);
             System.out.println(this.getName()+" = "+key + " : " + newValue);

           }

           //update every seconds
           try {
             Thread.sleep(1000);
           } catch (InterruptedException e) {
             e.printStackTrace();
           }
         }
       }
       public void stopWriter(){
         this.runForestRun = false;
         this.interrupt();
       }
       public String getNewValueFromDatastore(String key){
         //This part is not implemented. Out of scope of this artile
         return key;
       }
     }

lanjh 2008-12-22 14:57 发表评论

Jxcell

lanjh — Wed, 17 Dec 2008 06:15:00 GMT

Description:

Jxcell is a high performance spreadsheet component for java development environments that allows you to create, manipulate, and print excel worksheets.

Jxcell contains the tools needed to store, analyze, manipulate, and present your data in excel.

Jxcell directly using excel document format, support formulae, images, lines, chart.

Download Jxcell. (1950kb) ,containing examples of code

run Jxcell:
java -cp jxcell.jar com.jxcell.designer.Designer

run environment：

JDK1.3 and above version

screenshot

lanjh 2008-12-17 14:15 发表评论

Java的单线程Socket通信

lanjh — Thu, 11 Dec 2008 11:23:00 GMT

服务端：

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;

public class ServerSocket {

    public static void main(String[] args) {
        try {
            createServerSocket();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

    private static void createServerSocket() throws IOException {
        ServerSocket serverSocket = new ServerSocket(8189);
        Socket socket = serverSocket.accept();// wait for client connection
        while (true) {
            BufferedReader in = new BufferedReader(new InputStreamReader(socket
                    .getInputStream()));
            PrintWriter out = new PrintWriter(socket.getOutputStream());
            while (true) {
                String str = in.readLine();
                System.out.println("server:" + str);
                out.println("client receive" + str);
                out.flush();
                if (str.equals("exit"))
                    break;
            }
            socket.close();

        }
    }

}

客户端：

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.net.Socket;
import java.net.UnknownHostException;
import java.util.Scanner;


public class ClientSocket {
    private static final String URL = "localhost";

    private static final int PORT = 8189;


    /**
     * create client socket
     *
     * @throws IOException
     * @throws UnknownHostException
     *
     */
    private static void createClientSocket() throws UnknownHostException,
            IOException {
        Socket clientSocket = new Socket(URL, PORT);
        BufferedReader in = new BufferedReader(new InputStreamReader(
                clientSocket.getInputStream()));
        PrintWriter out = new PrintWriter(clientSocket.getOutputStream());
        BufferedReader wt = new BufferedReader(new InputStreamReader(System.in));
        while (true) {
            String str = wt.readLine();
            out.println("client send:" + str);
            out.flush();
            if (str.equals("end")) {
                break;
            }
            System.out.println(in.readLine());
        }
        clientSocket.close();

    }

    public static void main(String[] args) {

        try {
            createClientSocket();
        } catch (UnknownHostException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
}

lanjh 2008-12-11 19:23 发表评论

Java反射机制

lanjh — Sun, 05 Oct 2008 12:41:00 GMT

Java 的反射机制是使其具有动态特性的非常关键的一种机制，也是在JavaBean 中广泛应用的一种特性。
运用JavaBean 的最常见的问题是：根据指定的类名，类字段名和所对应的数据，得到该类的实例，下面的一个例子演示了这一实现。
-|Base.java //抽象基类
|Son1.java //基类扩展1
|Son2.java //基类扩展2
|Util.java
/**
* @author metaphy
* create 2005-4-14 9:06:56
* 说明：
*/
（1）Base.java 抽象基类只是一个定义
public abstract class Base {
}
（2）Son1.java /Son2.java 是已经实现的JavaBean
public class Son1 extends Base{
    private int id ;
    private String name ;

    public int getId() {
        return id;
    }
    public void setId(int id) {
        this.id = id;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }

    public void son1Method(String s){
        System.out.println(s) ;
    }
}
（3）
public class Son2 extends Base{
    private int id;
    private double salary;

    public int getId() {
        return id;
    }
    public void setId(int id) {
        this.id = id;
    }
    public double getSalary() {
        return salary;
    }
    public void setSalary(double salary) {
        this.salary = salary;
    }
}
（4）Util.java 演示了如何根据指定的类名，类字段名和所对应的数据，得到一个类的实例
import java.lang.reflect.Method;
public class Util {
    //此方法的最大好处是没有类名Son1,Son2 可以通过参数来指定，程序里面根本不用出现
    public static Base convertStr2ServiceBean(String beanName,String fieldSetter,String paraValue){
        Base base = null ;
        try {
            Class cls = Class.forName(beanName) ;
            base = (Base)cls.newInstance() ;
            Class[] paraTypes = new Class[]{String.class };
            Method method = cls.getMethod(fieldSetter, paraTypes) ;
            String[] paraValues = new String[]{paraValue} ;
            method.invoke(base, paraValues) ;
        } catch (Throwable e) {
            System.err.println(e);
        }
        return base ;
    }


    public static void main(String[] args){
        Son1 son1 =(Son1) Util.convertStr2ServiceBean("trying.reflect.Son1","setName","wang da sha");
        System.out.println("son1.getName() :"+son1.getName())  ;
    }
}
//调用结果：
//son1.getName() :wang da sha

谢谢！希望能给大家一点启发！
－－－－－－－－－－－－－－－－－－－－
附：
//下面这篇文档来源于Internet，作者不详
Reflection 是 Java 程序开发语言的特征之一，它允许运行中的 Java 程序对自身进行检查，或者说“自审”，并能直接操作程序的内部属性。例如，使用它能获得 Java 类中各成员的名称并显示出来。
Java 的这一能力在实际应用中也许用得不是很多，但是在其它的程序设计语言中根本就不存在这一特性。例如，Pascal、C 或者 C++ 中就没有办法在程序中获得函数定义相关的信息。
JavaBean 是 reflection 的实际应用之一，它能让一些工具可视化的操作软件组件。这些工具通过 reflection 动态的载入并取得 Java 组件(类) 的属性。
1. 一个简单的例子
考虑下面这个简单的例子，让我们看看 reflection 是如何工作的。
import java.lang.reflect.*;
public class DumpMethods {
   public static void main(String args[]) {
       try {
           Class c = Class.forName(args[0]);
           Method m[] = c.getDeclaredMethods();
           for (int i = 0; i < m.length; i++)
               System.out.println(m[i].toString());
       } catch (Throwable e) {
           System.err.println(e);
       }
   }
}
按如下语句执行：
java DumpMethods java.util.Stack
它的结果输出为：
public java.lang.Object java.util.Stack.push(java.lang.Object)
public synchronized java.lang.Object java.util.Stack.pop()
public synchronized java.lang.Object java.util.Stack.peek()
public boolean java.util.Stack.empty()
public synchronized int java.util.Stack.search(java.lang.Object)
这样就列出了java.util.Stack 类的各方法名以及它们的限制符和返回类型。
这个程序使用 Class.forName 载入指定的类，然后调用 getDeclaredMethods 来获取这个类中定义了的方法列表。java.lang.reflect.Methods 是用来描述某个类中单个方法的一个类。
2.开始使用 Reflection
用于 reflection 的类，如 Method，可以在 java.lang.relfect 包中找到。使用这些类的时候必须要遵循三个步骤：第一步是获得你想操作的类的 java.lang.Class 对象。在运行中的 Java 程序中，用 java.lang.Class 类来描述类和接口等。
下面就是获得一个 Class 对象的方法之一：
Class c = Class.forName("java.lang.String");
这条语句得到一个 String 类的类对象。还有另一种方法，如下面的语句：
Class c = int.class;
或者
Class c = Integer.TYPE;
它们可获得基本类型的类信息。其中后一种方法中访问的是基本类型的封装类 (如 Integer) 中预先定义好的 TYPE 字段。
第二步是调用诸如 getDeclaredMethods 的方法，以取得该类中定义的所有方法的列表。
一旦取得这个信息，就可以进行第三步了——使用 reflection API 来操作这些信息，如下面这段代码：
Class c = Class.forName("java.lang.String");
Method m[] = c.getDeclaredMethods();
System.out.println(m[0].toString());
它将以文本方式打印出 String 中定义的第一个方法的原型。
在下面的例子中，这三个步骤将为使用 reflection 处理特殊应用程序提供例证。
模拟 instanceof 操作符
得到类信息之后，通常下一个步骤就是解决关于 Class 对象的一些基本的问题。例如，Class.isInstance 方法可以用于模拟 instanceof 操作符：
class A {
}
public class instance1 {
   public static void main(String args[]) {
       try {
           Class cls = Class.forName("A");
           boolean b1 = cls.isInstance(new Integer(37));
           System.out.println(b1);
           boolean b2 = cls.isInstance(new A());
           System.out.println(b2);
       } catch (Throwable e) {
           System.err.println(e);
       }
   }
}
在这个例子中创建了一个 A 类的 Class 对象，然后检查一些对象是否是 A 的实例。Integer(37) 不是，但 new A() 是。
3.找出类的方法
找出一个类中定义了些什么方法，这是一个非常有价值也非常基础的 reflection 用法。下面的代码就实现了这一用法：
import java.lang.reflect.*;
public class method1 {
   private int f1(Object p, int x) throws NullPointerException {
       if (p == null)
           throw new NullPointerException();
       return x;
   }
   public static void main(String args[]) {
       try {
           Class cls = Class.forName("method1");
           Method methlist[] = cls.getDeclaredMethods();
           for (int i = 0; i < methlist.length; i++) {
               Method m = methlist[i];
               System.out.println("name = " + m.getName());
               System.out.println("decl class = " + m.getDeclaringClass());
               Class pvec[] = m.getParameterTypes();
               for (int j = 0; j < pvec.length; j++)
                   System.out.println("param #" + j + " " + pvec[j]);
               Class evec[] = m.getExceptionTypes();
               for (int j = 0; j < evec.length; j++)
                   System.out.println("exc #" + j + " " + evec[j]);
               System.out.println("return type = " + m.getReturnType());
               System.out.println("-----");
           }
       } catch (Throwable e) {
           System.err.println(e);
       }
   }
}
这个程序首先取得 method1 类的描述，然后调用 getDeclaredMethods 来获取一系列的 Method 对象，它们分别描述了定义在类中的每一个方法，包括 public 方法、protected 方法、package 方法和 private 方法等。如果你在程序中使用 getMethods 来代替 getDeclaredMethods，你还能获得继承来的各个方法的信息。
取得了 Method 对象列表之后，要显示这些方法的参数类型、异常类型和返回值类型等就不难了。这些类型是基本类型还是类类型，都可以由描述类的对象按顺序给出。
输出的结果如下：
name = f1
decl class = class method1
param #0 class java.lang.Object
param #1 int
exc #0 class java.lang.NullPointerException
return type = int
-----
name = main
decl class = class method1
param #0 class [Ljava.lang.String;
return type = void
-----

4.获取构造器信息
获取类构造器的用法与上述获取方法的用法类似，如：
import java.lang.reflect.*;
public class constructor1 {
   public constructor1() {
   }
   protected constructor1(int i, double d) {
   }
   public static void main(String args[]) {
       try {
           Class cls = Class.forName("constructor1");
           Constructor ctorlist[] = cls.getDeclaredConstructors();
           for (int i = 0; i < ctorlist.length; i++) {
               Constructor ct = ctorlist[i];
               System.out.println("name = " + ct.getName());
               System.out.println("decl class = " + ct.getDeclaringClass());
               Class pvec[] = ct.getParameterTypes();
               for (int j = 0; j < pvec.length; j++)
                   System.out.println("param #" + j + " " + pvec[j]);
               Class evec[] = ct.getExceptionTypes();
               for (int j = 0; j < evec.length; j++)
                   System.out.println("exc #" + j + " " + evec[j]);
               System.out.println("-----");
           }
       } catch (Throwable e) {
           System.err.println(e);
       }
   }
}
这个例子中没能获得返回类型的相关信息，那是因为构造器没有返回类型。
这个程序运行的结果是：
name = constructor1
decl class = class constructor1
-----
name = constructor1
decl class = class constructor1
param #0 int
param #1 double
-----
5.获取类的字段(域)
找出一个类中定义了哪些数据字段也是可能的，下面的代码就在干这个事情：

import java.lang.reflect.*;
public class field1 {
   private double d;
   public static final int i = 37;
   String s = "testing";
   public static void main(String args[]) {
       try {
           Class cls = Class.forName("field1");
           Field fieldlist[] = cls.getDeclaredFields();
           for (int i = 0; i < fieldlist.length; i++) {
               Field fld = fieldlist[i];
               System.out.println("name = " + fld.getName());
               System.out.println("decl class = " + fld.getDeclaringClass());
               System.out.println("type = " + fld.getType());
               int mod = fld.getModifiers();
               System.out.println("modifiers = " + Modifier.toString(mod));
               System.out.println("-----");
           }
       } catch (Throwable e) {
           System.err.println(e);
       }
   }
}
这个例子和前面那个例子非常相似。例中使用了一个新东西 Modifier，它也是一个 reflection 类，用来描述字段成员的修饰语，如“private int”。这些修饰语自身由整数描述，而且使用 Modifier.toString 来返回以“官方”顺序排列的字符串描述 (如“static”在“final”之前)。这个程序的输出是：
name = d
decl class = class field1
type = double
modifiers = private
-----
name = i
decl class = class field1
type = int
modifiers = public static final
-----
name = s
decl class = class field1
type = class java.lang.String
modifiers =
-----
和获取方法的情况一下，获取字段的时候也可以只取得在当前类中申明了的字段信息 (getDeclaredFields)，或者也可以取得父类中定义的字段 (getFields) 。

6.根据方法的名称来执行方法
文本到这里，所举的例子无一例外都与如何获取类的信息有关。我们也可以用 reflection 来做一些其它的事情，比如执行一个指定了名称的方法。下面的示例演示了这一操作：
import java.lang.reflect.*;
public class method2 {
   public int add(int a, int b) {
       return a + b;
   }
   public static void main(String args[]) {
       try {
           Class cls = Class.forName("method2");
           Class partypes[] = new Class[2];
           partypes[0] = Integer.TYPE;
           partypes[1] = Integer.TYPE;
           Method meth = cls.getMethod("add", partypes);
           method2 methobj = new method2();
           Object arglist[] = new Object[2];
           arglist[0] = new Integer(37);
           arglist[1] = new Integer(47);
           Object retobj = meth.invoke(methobj, arglist);
           Integer retval = (Integer) retobj;
           System.out.println(retval.intvalue());
       } catch (Throwable e) {
           System.err.println(e);
       }
   }
}
假如一个程序在执行的某处的时候才知道需要执行某个方法，这个方法的名称是在程序的运行过程中指定的 (例如，JavaBean 开发环境中就会做这样的事)，那么上面的程序演示了如何做到。
上例中，getMethod 用于查找一个具有两个整型参数且名为 add 的方法。找到该方法并创建了相应的 Method 对象之后，在正确的对象实例中执行它。执行该方法的时候，需要提供一个参数列表，这在上例中是分别包装了整数 37 和 47 的两个 Integer 对象。执行方法的返回的同样是一个 Integer 对象，它封装了返回值 84。
7.创建新的对象
对于构造器，则不能像执行方法那样进行，因为执行一个构造器就意味着创建了一个新的对象 (准确的说，创建一个对象的过程包括分配内存和构造对象)。所以，与上例最相似的例子如下：
import java.lang.reflect.*;
public class constructor2 {
   public constructor2() {
   }
   public constructor2(int a, int b) {
       System.out.println("a = " + a + " b = " + b);
   }
   public static void main(String args[]) {
       try {
           Class cls = Class.forName("constructor2");
           Class partypes[] = new Class[2];
           partypes[0] = Integer.TYPE;
           partypes[1] = Integer.TYPE;
           Constructor ct = cls.getConstructor(partypes);
           Object arglist[] = new Object[2];
           arglist[0] = new Integer(37);
           arglist[1] = new Integer(47);
           Object retobj = ct.newInstance(arglist);
       } catch (Throwable e) {
           System.err.println(e);
       }
   }
}
根据指定的参数类型找到相应的构造函数并执行它，以创建一个新的对象实例。使用这种方法可以在程序运行时动态地创建对象，而不是在编译的时候创建对象，这一点非常有价值。
8.改变字段(域)的值
reflection 的还有一个用处就是改变对象数据字段的值。reflection 可以从正在运行的程序中根据名称找到对象的字段并改变它，下面的例子可以说明这一点：
import java.lang.reflect.*;
public class field2 {
   public double d;
   public static void main(String args[]) {
       try {
           Class cls = Class.forName("field2");
           Field fld = cls.getField("d");
           field2 f2obj = new field2();
           System.out.println("d = " + f2obj.d);
           fld.setDouble(f2obj, 12.34);
           System.out.println("d = " + f2obj.d);
       } catch (Throwable e) {
           System.err.println(e);
       }
   }
}
这个例子中，字段 d 的值被变为了 12.34。
9.使用数组
本文介绍的 reflection 的最后一种用法是创建的操作数组。数组在 Java 语言中是一种特殊的类类型，一个数组的引用可以赋给 Object 引用。观察下面的例子看看数组是怎么工作的：
import java.lang.reflect.*;
public class array1 {
   public static void main(String args[]) {
       try {
           Class cls = Class.forName("java.lang.String");
           Object arr = Array.newInstance(cls, 10);
           Array.set(arr, 5, "this is a test");
           String s = (String) Array.get(arr, 5);
           System.out.println(s);
       } catch (Throwable e) {
           System.err.println(e);
       }
   }
}
例中创建了 10 个单位长度的 String 数组，为第 5 个位置的字符串赋了值，最后将这个字符串从数组中取得并打印了出来。
下面这段代码提供了一个更复杂的例子：
import java.lang.reflect.*;
public class array2 {
   public static void main(String args[]) {
       int dims[] = new int[]{5, 10, 15};
       Object arr = Array.newInstance(Integer.TYPE, dims);
       Object arrobj = Array.get(arr, 3);
       Class cls = arrobj.getClass().getComponentType();
       System.out.println(cls);
       arrobj = Array.get(arrobj, 5);
       Array.setInt(arrobj, 10, 37);
       int arrcast[][][] = (int[][][]) arr;
       System.out.println(arrcast[3][5][10]);
   }
}
例中创建了一个 5 x 10 x 15 的整型数组，并为处于 [3][5][10] 的元素赋了值为 37。注意，多维数组实际上就是数组的数组，例如，第一个 Array.get 之后，arrobj 是一个 10 x 15 的数组。进而取得其中的一个元素，即长度为 15 的数组，并使用 Array.setInt 为它的第 10 个元素赋值。
注意创建数组时的类型是动态的，在编译时并不知道其类型。

lanjh 2008-10-05 20:41 发表评论