Javassist是一个开源的分析、编辑和创建Java字节码的类库。是由东京工业大学的数学和计算机科学系的 Shigeru Chiba （千叶 滋）所创建的。它已加入了开放源代码JBoss 应用服务器项目,通过使用Javassist对字节码操作为JBoss实现动态AOP框架。
　　关于java字节码的处理，目前有很多工具，如bcel，asm。不过这些都需要直接跟虚拟机指令打交道。如果你不想了解虚拟机指令，可以采用javassist。javassist是jboss的一个子项目，其主要的优点，在于简单，而且快速。直接使用java编码的形式，而不需要了解虚拟机指令，就能动态改变类的结构，或者动态生成类。

<?xml version="1.0" encoding="UTF-8"?>

<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
        "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">

<hibernate-mapping default-access="field">

    <class name="com.aaxis.model.Person" table="person" dynamic-insert="true" dynamic-update="true"
           select-before-update="true">
        <id name="id" column="id" type="java.lang.Integer">
            <generator class="native"/>
        </id>
        <version name="version" column="version" type="java.lang.Long"/>
        <property name="active" column="active" type="java.lang.Boolean"/>
        <property name="name" column="name" type="java.lang.String"/>
        <property name="description" column="description" type="java.lang.String"/>
    </class>

</hibernate-mapping>

<?xml version='1.0' encoding='utf-8'?>

<!DOCTYPE hibernate-configuration PUBLIC
        "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
        "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">

<hibernate-configuration>

    <session-factory>

        <!-- Database connection settings -->
        <property name="connection.driver_class">com.mysql.jdbc.Driver</property>
        <property name="connection.url">jdbc:mysql://localhost:3306/couple?createDatabaseIfNotExist=true&useUnicode=true&characterEncoding=utf-8</property>
        <property name="connection.username">root</property>
        <property name="connection.password">root</property>

        <!-- JDBC connection pool (use the built-in) -->
        <property name="connection.pool_size">1</property>

        <!-- SQL dialect -->
        <property name="dialect">org.hibernate.dialect.MySQL5Dialect</property>

        <!-- Enable Hibernate's automatic session context management -->
        <property name="current_session_context_class">thread</property>

        <!-- Disable the second-level cache -->
        <property name="cache.use_second_level_cache">false</property>
        <property name="cache.provider_class">org.hibernate.cache.NoCacheProvider</property>

        <property name="jdbc.batch_size">100</property>

        <property name="jdbc.fetch_size">10</property>

        <!-- Echo all executed SQL to stdout -->
        <property name="show_sql">true</property>

        <!-- Format all executed SQL to stdout -->
        <property name="format_sql">true</property>

        <property name="hibernate.use_sql_comments">true</property>

        <!-- Drop and re-create the database schema on startup -->
        <property name="hbm2ddl.auto">update</property>

        <mapping resource="hibernate/mappings/Person.hbm.xml"/>
    </session-factory>

</hibernate-configuration>

package com.dream.channel;

import junit.framework.TestCase;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.nio.ByteBuffer;
import java.nio.channels.FileChannel;

/**
 * Created by IntelliJ IDEA.
 * User: Zhong Gang
 * Date: 11-10-5
 * Time: 上午10:19
 */
public class ChannelTest extends TestCase {

    public void testFileChannelCopy() throws Exception {
        long start = System.currentTimeMillis();

        FileInputStream fileInputStream = new FileInputStream("G:\\The.Big.Bang.Theory.S05E01.720p.HDTV.x264-IMMERSE.mkv");
        FileOutputStream fileOutputStream = new FileOutputStream("G:\\TBBT.mkv");

        FileChannel fileInputStreamChannel = fileInputStream.getChannel();
        FileChannel fileOutputStreamChannel = fileOutputStream.getChannel();

        ByteBuffer buffer = ByteBuffer.allocate(1024);

        while (true) {
            buffer.clear();

            int read = fileInputStreamChannel.read(buffer);

            if (read == -1) {
                break;
            }

            buffer.flip();

            fileOutputStreamChannel.write(buffer);
        }

        long end = System.currentTimeMillis();

        System.out.println("Time spend is " + (end - start));

    }

    public void testFileCopy() throws Exception {
        long start = System.currentTimeMillis();

        FileInputStream fileInputStream = new FileInputStream("G:\\The.Big.Bang.Theory.S05E01.720p.HDTV.x264-IMMERSE.mkv");
        FileOutputStream fileOutputStream = new FileOutputStream("G:\\TBBT.mkv");

        int read = fileInputStream.read();
        while (read != -1) {
            fileOutputStream.write(read);

            read = fileInputStream.read();
        }

        long end = System.currentTimeMillis();

        System.out.println("Time spend is " + (end - start));

    }

    public void testFileBufferCopy() throws Exception {
        long start = System.currentTimeMillis();

        FileInputStream fileInputStream = new FileInputStream("G:\\read.txt");
        FileOutputStream fileOutputStream = new FileOutputStream("G:\\write.txt");

        BufferedInputStream bufferedInputStream = new BufferedInputStream(fileInputStream);
        BufferedOutputStream bufferedOutputStream = new BufferedOutputStream(fileOutputStream);

        int read = bufferedInputStream.read();

        while (read != -1) {
            bufferedOutputStream.write(read);

            read = bufferedInputStream.read();
        }

        bufferedOutputStream.flush();

        long end = System.currentTimeMillis();

        System.out.println("Time spend is " + (end - start));

    }
}

-Xms512m -Xmx1024m -XX:PermSize=128m -XX:MaxPermSize=256m

        <!-- commons fileupload dependencies -->
        <dependency>
            <groupId>commons-fileupload</groupId>
            <artifactId>commons-fileupload</artifactId>
            <version>1.2.2</version>
        </dependency>
        <dependency>
            <groupId>commons-io</groupId>
            <artifactId>commons-io</artifactId>
            <version>2.0.1</version>
        </dependency>

import junit.framework.TestCase;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;
import org.hibernate.classic.Session;

import java.util.Properties;

/**
 * Created by IntelliJ IDEA.
 * User: Zhong Gang
 * Date: 11-8-8
 * Time: 下午10:03
 */
public class UserDaoImplTest extends TestCase {
    private SessionFactory sessionFactory = null;

    @Override
    public void setUp() throws Exception {
        Properties properties = new Properties();
        properties.setProperty("hibernate.connection.driver_class", "com.mysql.jdbc.Driver");
        properties.setProperty("hibernate.connection.url", "jdbc:mysql://localhost:3306/demo");
        properties.setProperty("hibernate.connection.username", "root");
        properties.setProperty("hibernate.connection.password", "root");

        Configuration configuration = new Configuration();
        configuration.addResource("hibernate_mappings/User.hbm.xml");
        configuration.addResource("hibernate_mappings/Authority.hbm.xml");
        configuration.addResource("hibernate_mappings/Husband.hbm.xml");
        configuration.addResource("hibernate_mappings/Person.hbm.xml");
        configuration.addResource("hibernate_mappings/Role.hbm.xml");
        configuration.addResource("hibernate_mappings/Wife.hbm.xml");
        configuration.setProperties(properties);
        sessionFactory = configuration.buildSessionFactory();
    }

    public void testUsersCount() {
        Session session = sessionFactory.openSession();
        boolean connected = session.isConnected();
        assertTrue(connected);
    }
}

　　一。引入url rewriter
　　<dependency>
            <groupId>org.tuckey</groupId>
            <artifactId>urlrewritefilter</artifactId>
            <version>3.1.0</version>
    </dependency>

　　二。配置UrlRewriterFilter
　　<filter>
        <filter-name>urlRewriteFilter</filter-name>
        <filter-class>org.tuckey.web.filters.urlrewrite.UrlRewriteFilter</filter-class>
    </filter>
    <filter-mapping>
        <filter-name>urlRewriteFilter</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>

　　三。配置urlrewriter.xml　该配置文件需要放在WEB-INF根目录下，如果需要配置自定义的urlrewriter.xml文件位置，那么需要在urlRewriterFilter中配置configPath参数

　　urlrewriter.xml举例

　　<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE urlrewrite PUBLIC "-//tuckey.org//DTD UrlRewrite 3.0//EN"
        "http://tuckey.org/res/dtds/urlrewrite3.0.dtd">
<urlrewrite>
    <rule>
        <from>/index.html$</from>
        <to>/index.jsp</to>
    </rule>
    <outbound-rule>
        <from>/index.jsp</from>
        <to>/index.html</to>
    </outbound-rule>
</urlrewrite>  

package com.template.guice;

/**
 * Created by IntelliJ IDEA.
 * User: Zhong Gang
 * Date: 11-8-6
 * Time: 下午3:16
 */
public class DBConnection {
    private static final String DRIVER_CLASS_NAME = "com.mysql.jdbc.Driver";
    private static final String URL = "jdbc:mysql://localhost:3306/demo";
    private static final String URERNAME = "root";
    private static final String PASSWORD = "root";

    private String driverClassName;
    private String url;
    private String username;
    private String password;

    private static DBConnection ourInstance = new DBConnection(DRIVER_CLASS_NAME, URL, URERNAME, PASSWORD);

    public static DBConnection getInstance() {
        return ourInstance;
    }

    private DBConnection() {
    }

    private DBConnection(String driverClassName, String url, String username, String password) {
        this.driverClassName = driverClassName;
        this.url = url;
        this.username = username;
        this.password = password;
    }
}