JAVA2JSP学习的门槛相对比较的高
所涉及的专业技术语也是很多
下面是我自己搜录的，请看：
J2SE = Java 2 Standard Edition = Java2标准版
J2EE = Java 2 Enterprise Edition = Java2企业版（包括JSP/Servlet、EJB、JNDI、JTA等）
J2SDK == JDK = Java 2 Standard Development Kit = Java2标准开发工具集
J2RE == JRE = Java 2 Runtime Environment = Java2运行时环境
JVM == Java Virtual Machine = Java虚拟机
J2SDK内是包含J2RE的，所以一般来说，下载了J2SDK，就既有编译调试Java程序的功能，又能执行Java应用程序（Java Application）和Java小程序(Java Applet)。但如果只有J2RE，则不能编译调试Java程序(没有javac命令，不能编译Java源代码)，仅能运行Java程序（在MS-DOS窗口的命令行执行或双击.jar图标执行）和在浏览器（IE/Navigator/Mozilla）里运行Java小程序。如果你已经安装了JBuilder或WebLogic Server，它们已经自带了jdk1.3.1（按其具体位置（如“c:\jbuilder7\jdk1.3”或“c:\bea\jdk131_03”）设置所需的JAVA_HOME环境变量的值），可以不必下载网上的j2sdk 1.4.2。
其中Java2 Platform 平台包括了如下内容
<HTML>
<HEAD>
<title>New Features</title>
</HEAD>
<BODY BGCOLOR="#FFFFFF">
<TABLE summary="layout" BORDER="0" WIDTH="100%">
<TR>
<!--TD WIDTH=60-->
<TD>
<IMG SRC="../images/javalogo52x88.gif" ALT="Java" BORDER=0 WIDTH=52 HEIGHT=88>
</TD>
<TD>
<center>
<h1>Java<sup><font size="-2">TM</font></sup> 2 SDK, Standard Edition, version 1.4.2<br>Summary of New Features and Enhancements</h1>
</center>
</TD>
<TD ALIGN=RIGHT VALIGN=TOP>
<font size="-1"><a href="../index.html">Contents</a></font>
<p>
<!-- Ja
<A HREF="../../ja/docs/ja/relnotes/features.html"><IMG SRC="../images/Japanese12B.gif" border="0" ALT="Japanese"></TD>
-->
</TR>
</TABLE>
<!-- Body text begins here -->
<hr size=3 noshade>
<p>
<blockquote>
Version 1.4.0 of the Java 2 SDK, Standard Edition was a major feature
release. The features listed below are those introduced in 1.4.0 (since 1.3).
Version 1.4.2 is a maintenance release and introduces the minor enhancements and
changes (since 1.4.1) listed at
<a href="http://java.sun.com/j2se/1.4.2/changes.html">Enhancements
and Changes in J2SE 1.4.2</a> on the web site.
<p>
The <em>full</em> list of features, including features brought forward
from previous versions, is available at
<a href="../index.html#guide">Guide to Features</a>.
</blockquote>
<p>
<blockquote>
<dl>
<dt><dd><b>Java 2 Platform</b>
<ul>
<li><a href="#xmlprocessing">XML Processing</a>
<li><a href="#nio">New I/O APIs</a>
<li><a href="#security">Security</a>
<li><a href="#2d">Java 2D<sup><font size="-2">TM</font></sup> technology</a>
<li><a href="#imageio">Image I/O Framework</a>
<li><a href="#jps">Java Print Service</a>
<li><a href="#awt">AWT</a>
<li><a href="#Swing">Swing</a>
<li><a href="#dnd">Drag and Drop</a>
<li><a href="#logging">Logging API</a>
<li><a href="#jws">Java<sup><font size="-2">TM</font></sup> Web Start Product</a>
<li><a href="#persistence">Long-term Persistence of
JavaBeans<sup><font size="-2">TM</font></sup> Components</a>
<li><a href="#jdbc">JDBC<sup><font size="-2">TM</font></sup> 3.0 API</a>
<li><a href="#assertions">Assertion Facility</a>
<li><a href="#preferences">Preferences API</a>
<li><a href="#chained-exceptions">Chained Exception Facility</a>
<li><a href="#standards">Endorsed Standards Override Mechanism</a>
<li><a href="#vm">Java Virtual Machines</a>
<li><a href="#performance">Performance</a>
<li><a href="#networking">Networking Support, Including IPv6</a>
<li><a href="#rmi">RMI</a>
<li><a href="#serialization">Serialization</a>
<li><a href="#jndi">Java Naming and Directory Interface<sup><font size="-2">TM</font></sup> (JNDI)</a>
<li><a href="#corba">CORBA, Java IDL, and RMI-IIOP</a>
<li><a href="#jpda">Java<sup><font size="-2">TM</font></sup> Platform Debugger Architecture</a>
<li><a href="#i18n">Internationalization</a>
<li><a href="#plugin">Java<sup><font size="-2">TM</font></sup> Plug-in Product</a>
<li><a href="#collections">Collections Framework</a>
<li><a href="#access">Accessibility</a>
<li><a href="#regex">Regular Expressions</a>
<li><a href="#math">Math</a>
<li><a href="#reflection">Reflection</a>
<li><a href="#jni">Java Native Interface</a>
</ul>
<dt><dd><b>Tools</b>
<ul>
<li><a href="#tools">Tools and Utilities</a>
</ul>
</dl>
</blockquote>
<hr>
<!--=========================== JAVA PLATFORM =========================-->
<a name=java2platform></a>
<h2>Java 2 Platform</h2>
<a name=xmlprocessing></a>
<ul>
<li><b><a href=../guide/xml/jaxp/index.html>XML Processing</a></b>
<blockquote><b>The Java<font size="1"><sup>TM</sup></font> API for XML
processing</b> has been added to the Java 2 Platform. It provides basic
support for processing XML documents through a standardized set of
Java Platform APIs.
</blockquote>
<p>
<a name=nio></a>
<li><b><a href="../guide/nio/index.html">New I/O APIs</a></b><br>
<blockquote>
The <b>new I/O (NIO) APIs</b> provide new features and improved
performance in the areas of buffer management, character-set support,
regular-expression matching, file I/O, and scalable network I/O.
</blockquote>
<p>
<a name=security></a>
<li><b><a href="../guide/security/index.html">Security</a></b>
<ul>
<li>The <b><a href="../guide/security/jce/JCERefGuide.html">
Java<SUP><FONT SIZE=-2>TM</FONT></SUP> Cryptography Extension
(JCE)</a></b>,
<b><a href="../guide/security/jsse/JSSERefGuide.html">
Java<SUP><FONT SIZE=-2>TM</FONT></SUP> Secure Socket Extension
(JSSE)</a></b>, and <b><a href="../guide/security/jaas/JAASRefGuide.html">
Java<SUP><FONT SIZE=-2>TM</FONT></SUP> Authentication
and Authorization Service (JAAS)</a></b> security features have now been
integrated into the Java<SUP><FONT SIZE=-2>TM</FONT></SUP> 2 SDK,
Standard Edition (Java 2 SDK), v 1.4 rather than being optional packages.
<li><b>There are two new security features</b>:
<ul>
<li>The <b><a href="../guide/security/jgss/tutorials/index.html">
Java<SUP><FONT SIZE=-2>TM</FONT></SUP> GSS-API</a></b>
can be used for securely exchanging messages between communicating
applications using the Kerberos V5 mechanism.
<li>The <b><a href="../guide/security/certpath/CertPathProgGuide.html">
Java<font size=-2><sup>TM</sup></font> Certification Path API</a></b>
includes new classes and methods in the <code>java.security.cert</code>
package that allow you to build and validate certification paths
(also known as "certificate chains").
</ul>
<li>Due to import control restrictions, <b>the JCE jurisdiction policy files
shipped with the Java 2 SDK, v 1.4 allow "strong" but limited cryptography
to be used.</b>
An "unlimited" version of these files indicating no restrictions on
cryptographic strengths is available.
<li>The JSSE implementation provided in this release includes
strong cipher suites. However, due to U.S. export control
restrictions, <B>this release does not allow alternate "pluggable"
SSL/TLS implementations to be used.</b>
For more information, please see the
<a href="../guide/security/jsse/JSSERefGuide.html#Customization">JSSE Reference Guide</a>.
<li>With the integration of JAAS into the Java 2 SDK, the
<code>java.security.Policy</code> API handles Principal-based queries,
and the default policy implementation supports Principal-based
<code>grant</code> entries. Thus, <b>access control can now be based
not just on what code is running, but also on <i>who</i>
is running it</b>.
<li><b>Support for dynamic policies</b> has been added. In Java 2 SDK
releases prior to version 1.4, classes were statically bound with
permissions by querying security policy during class loading. The
lifetime of this binding was scoped by the lifetime of the class
loader. In version 1.4 this binding is now deferred until needed by
a security check. The lifetime of the binding is now scoped by the
lifetime of the security policy.
<li>The graphical <b>Policy Tool</b> utility has been enhanced to
enable specifying a Principal field indicating what user is to
be granted specified access control permissions.
</ul>
<p>
<a name="2d"></a>
<li><b><a href="../guide/2d/index.html">Java 2D<sup><font size="-2">TM</font></sup> Technology</a></b>
<blockquote>
<b>Java 2D</b> includes many new features including: performance
improvements, support for hardware acceleration for offscreen images,
a pluggable image I/O framework, a new print service API, and several new
font features.
</blockquote>
<p>
<a name="imageio"></a>
<li><b><a href="../guide/imageio/index.html">Image I/O Framework</a></b>
<blockquote>
The <b>Java Image I/O Framework</b> provides a pluggable architecture
for working with images stored in files and accessed across the network.
It offers substantially more flexibility and power than the current APIs
for loading and saving images.
</blockquote>
<p>
<a name="jps">
<li><b><a href="../guide/jps/index.html">Java Print Service API</a></b>
<blockquote>
The Java<sup><font size="-1">TM</font></sup> Print Service is a new Java
Print API that enables client and server applications to:
<ul>
<li>Discover and select print services based on their capabilities
<li>Specify the format of print data
<li>Submit print jobs to services that support the document type to be
printed.
</ul>
</blockquote>
<a name="awt"></a>
<li><b><a href="../guide/awt/index.html">AWT</a></b>
<blockquote>
Changes to the AWT package center on improving the robustness,
behavior, and performance of programs that present a graphical
user interface.
A new <b>focus architecture</b> replaces the previous implementation and
addresses many focus-related bugs caused by platform inconsistencies,
and incompatibilities between AWT and Swing components.
The new <b>full-screen exclusive mode API</b> supports high performance
graphics by suspending the windowing system so that drawing can be
done directly to the screen; a benefit to applications like games,
or other rendering-intensive applications.
<b>Headless support</b>
is now enabled by new graphics environment methods that
indicate whether a display, keyboard, and mouse can be supported in a
graphics environment. The ability to disable native frame decorations
is now available for applications which need to take full control of specifying how a frame will look; when
enabled this prevents the rendering of a native titlebar, system menu, border, or other
native operating system dependent screen components.
The oft-requested <b>mouse wheel</b>, with a scroll wheel in place of
the middle mouse button, is enabled with new built-in Java support
for scrolling via the mouse wheel. Also, a new mouse wheel listener
class allows customization of mouse wheel behavior. The AWT package
has been modified to be fully <b>64-bit compliant</b> and now runs on
Solaris machines with 64-bit and 32-bit addresses.
</blockquote>
<p>
<a name="Swing"></a>
<li><b><a href="../guide/swing/index.html">Swing</a></b>
<blockquote>
Many new features have been added to Swing. The new <b>spinner</b> component
is a single line input field that allows the user to select a number or
a value by cycling through a sequence of values using a tiny pair of up/down arrow buttons.
The new <b>formatted text field</b> component allows formatting of dates,
numbers, and strings, such as a text field that accepts only decimal money values.
The <b>Windows look and feel</b> implementation is updated to track features
available in the 2000/98 versions.
A new <b>drag and drop architecture</b> provides seamless drag and drop
support between components as well as an easy way to implement drag and
drop in your customized Swing components - writing a couple of methods
which describe the particulars of your data model is all that is required.
Swing's progress bar component has been enhanced to support an
indeterminate state; rather than showing the degree of completeness,
the <b>indeterminate progress bar</b> uses constant animation to show that
a time-consuming operation is occurring. Due to great customer demand,
the tabbed pane component has been enhanced to support <b>scrollable tabs</b>.
With this feature enabled, if all the tabs will not fit within a single tab run,
the tabbed pane component will display a single, scrollable run of tabs, instead
of wrapping the tabs onto multiple runs. The <b>popup and popup factory</b> classes,
which were previously package private, have been exposed and made public so
that programmers may customize or create their own popups. The new <b>focus
architecture</b> is fully integrated into Swing.
</blockquote>
<p>
<a name=dnd></a>
<li><b><a href="../guide/dragndrop">Drag and Drop</a></b>
<blockquote>
Swing has added support for data transfer between
applications. A drag and drop operation is a data transfer request
that has been specified by a gesture with a
graphical pointing device. In the case of copy/paste, data transfer
is often initiated with the keyboard. The ability
to transfer data takes two forms: Drag and drop (DnD) support and
clipboard transfer via cut/copy/paste. See
<a href="../guide/swing/1.4/dnd.html"><b>Swing Data Transfer</b></a>.
</blockquote>
<p>
<a name=logging></a>
<li><b><a href="../guide/util/logging/index.html">Logging API</a></b>
<blockquote>
The Java Logging APIs facilitate software servicing and maintenance
at customer sites by producing log reports suitable for analysis by
end users, system administrators, field service engineers, and
software development teams. The Logging APIs capture information
such as security failures, configuration errors, performance bottlenecks,
and/or bugs in the application or platform.
</blockquote>
<p>
<a name=jws></a>
<li><b><a href="../guide/jws/index.html">Java<sup><font size="-2">TM</font></sup> Web Start Product</a></b>
<blockquote>
The Java Web Start product is a new application-deployment technology
that is bundled with J2SE 1.4.0.
With Java Web Start, you launch applications simply by clicking on a
Web page link. If the application is not present on your computer,
Java Web Start automatically downloads all necessary files. It then
caches the files on your computer so the application is always ready to
be relaunched anytime you want -- either from an icon on your
desktop or from the browser link. And no matter which method you
use to launch the application, the most current version of the
application is always presented to you.
</blockquote>
<p>
<a name=persistence></a>
<li><b><a href="../guide/beans/index.html">Long-term Persistence
of JavaBeans Components</a></b>
<blockquote>
The new persistence model is designed to handle the process of
converting a graph of beans to and from a persistent form.
The new API is suitable for creating archives of graphs of
JavaBeans components as textual representations of their properties.
See
<a href="http://java.sun.com/j2se/1.4.2/docs/guide/beans/changes14.html">API
Enhancements to the JavaBeans Component API</a>.
</blockquote>
<p>
<a name=jdbc></a>
<li><b><a href="../guide/jdbc/index.html">JDBC 3.0 API</a></b>
<blockquote>
The JDBC 3.0 API, comprised of packages <tt>java.sql</tt> and
<tt>javax.sql</tt>, provides universal data access from the Java programming
language. Using the JDBC 3.0 API, you can access virtualy any data
source, from relational databases to spreadsheets and flat files. JDBC technology also provides a common base on which tools and alternative interfaces
can be built.
<p>
New features include the ability to set savepoints in a transaction, to keep
result sets open after a transaction is committed, to reuse prepared statements,
to get metadata about the parameters to a prepared statement, to retrieve
keys that are automatically generated, and to have multiple result sets open
at one time. There are two new JDBC data types, BOOLEAN and DATALINK, with
the DATALINK type making it possible to manage data outside of a data source.
This release also establishes the relationship between the JDBC Service Provider
Interface and the Connector architechture.
</blockquote>
<p>
<a name=assertions></a>
<li><b><a href="../guide/lang/assert.html">Assertion Facility</a></b>
<blockquote>
An assertion facility has been added to the Java 2 Platform.
Assertions are boolean expressions that the programmer believes to be true
concerning the state of a computer program. For example, after sorting a
list, the programmer might assert that the list is in ascending order.
Evaluating assertions at runtime to confirm their validity is one of the most
powerful tools for improving code quality, as it quickly uncovers the
programmer's misconceptions concerning a program's behavior.
</blockquote>
<p>
<a name=preferences></a>
<li><b><a href="../guide/lang/preferences.html">Preferences API</a></b>
<blockquote>
This new feature is a simple API for managing user preference and
configuration data. Applications require preference and configuration
data to adapt to different users, environments and needs. Applications
need a way to store, retrieve, and modify this data. This need is met
by the Preferences API. The Preferences API is intended to replace
most common uses of class <tt>java.util.Properties</tt>, rectifying many
of its deficiencies, while retaining its light weight.
</blockquote>
<p>
<a name=standards></a>
<li><b><a href="../guide/standards/index.html">Endorsed Standards
Override Mechanism</b></a>
<blockquote>
An <em>endorsed standard</em> is a Java<sup><font size="-2">TM</font></sup
>
API defined through a standards process other than the
<a href="http://www.jcp.org/">Java
Community Process</a><sup><font size="-2">SM</font></sup>
(JCP<sup><font size="-2">SM</font></sup>).
Because endorsed standards are defined outside the JCP, it
is anticipated that such standards may be revised between
releases of the Java 2 Platform. In order to take advantage of
new revisions to endorsed standards, developers and software vendors
may use the <a href="../guide/standards/index.html">Endorsed
Standards Override Mechanism</a> to provide
newer versions of an endorsed standard than those included
in the Java 2 Platform as released by Sun Microsystems.
</blockquote>
<p>
<a name=chained-exceptions></a>
<li><b><a href="../guide/lang/chained-exceptions.html">Chained Exception
Facility</a></b>
<blockquote>
This new facility provides
a common API to record the fact that one exception caused
another, to access causative exceptions, and to acess the
entire "causal chain" as part of the standard stack backtrace, ensuring that
preexisting programs will provide this information with no additional effort
on the part of their authors.
</blockquote>
<p>
<a name="vm"></a>
<li><b><a href="../guide/vm/index.html">Java Virtual Machines</a></b>
<blockquote>
The Java virtual machines in this release include several enhancements.
<ul>
<li>Signal-chaining facility.
<li>64-bit support on Solaris<sup><font size="-2">TM</font></sup>-SPARC<sup><font size="-2">TM</font></sup> platform edition.
<li>Error-reporting mechanism.
<li>New command-line option for performing additional Java Native
Interface (JNI) checks.
<li>New facility for logging garbage-collection events.
</ul>
The Classic virtual machine is no longer shipped as part of the
Java 2 SDK.
</blockquote>
<p>
<a name="performance"></a>
<li><b><a href="../guide/performance/index.html">Performance</a></b>
<blockquote>
This release includes performance enhancements in many areas of
the platform. See <a href="../guide/performance/speed.html">Performance
Enhancements</a> for a description of some of them.
</blockquote>
<p>
<a name="networking"></a>
<li><b><a href="../guide/net/index.html">Networking Support, Including IPv6</a></b>
<blockquote>
<a href="../guide/net/enhancements14.html">New features</a> include
support for IPv6 in TCP- and UDP-based applications,
and support for unconnected/unbound sockets, allowing more flexible socket
creation, binding, and connection. A mechanism called Java Secure Socket
Extension provides encryption for data sent via sockets, and a new class,
<a href="../api/java/net/URI.html"><code>URI</code></a>, allows URI
construction and parsing without the presence of a protocol
handler. The FTP Protocol Handler has been overhauled for conformity to
current standards. The default character set is now UTF8, and APIs have
been added to enable other character schemes.
<p>A new class, <a href="../api/java/net/NetworkInterface.html"><code>NetworkInterface</code></a>, allows enumeration of interfaces and addresses,
and JNDI DNS SP Support in <a href="../api/java/net/InetAddress.html"><code>InetAddress</code></a> enables applications to configure a pure
Java name service provider. TCP out-of-band data provides support for legacy
applications; a UDP Connection function registers destination address with
the OS, enabling asynchronous errors to be returned on the UDP socket; and
full SOCkS V5 and V4 TCP support includes auto-negotiation with the proxy
for which version to use. In addition, there are improvements to streaming,
request and response headers processing, and error handling.
</blockquote>
<p>
<a name="rmi"></a>
<li><b><a href="../guide/rmi/index.html">RMI</a></b>
<blockquote>
<b>Server-side Stack Traces Now Retained in Remote Exceptions</b><br>
The RMI runtime implementation will now preserve the server-side
stack trace information of an exception that is thrown from a
remote call, in addition to filling in the client-side stack
trace as it did previous releases. Therefore, when such an
exception becomes accessible to client code, its stack trace
will now contain all of its original server-side trace data
followed by the client-side trace.
<p>
<b>Service Provider Interface for <code>RMIClassLoader</code></b><br>
Certain static methods of
<code>java.rmi.server.RMIClassLoader</code> now delegate their
behavior to an instance of a new service provider interface,
<code>java.rmi.server.RMIClassLoaderSpi</code>. This service
provider object can be configured to augment RMI's dynamic
class loading behavior for a given application. By default, the
service provider implements the standard behavior of all of the
static methods in <code>RMIClassLoader</code>. See the class
documentation of <code><a href="../api/java/rmi/server/RMIClassLoader.html">RMIClassLoader</a></code> and
<code><a href="../api/java/rmi/server/RMIClassLoaderSpi.html">RMIClassLoaderSpi</a></code> for more details.
<p>
<b>Dynamic Server Host Name</b><br>
The <code>java.rmi.server.hostname</code> property can now be
dynamically updated to indicate that future exports should use a
new host name. Therefore, the new host name value will be contained
in the stub for an object that is exported after the property is
updated.
</blockquote>
<p>
<a name="serialization"></a>
<li><b><a href="../guide/serialization/index.html">Serialization</a></b>
<blockquote>
This release has several <a href="../guide/serialization/relnotes14.html">changes and enhancements</a> to the serialization API, including
<ul>
<li>Support for deserialization of objects that are
known to be unshared in the data-serialization stream.
<li>Support for a class-defined readObjectNoData method.
<li>Important bug fixes.
</ul>
</blockquote>
<p>
<a name="jndi"></a>
<li><b><a href="../guide/jndi/index.html">Java Naming and Directory Interface<sup><font size="-2">TM</font></sup> (JNDI)</a></b>
<ul>
<li>An Internet Domain Naming System (DNS) service provider is part of the
Java 2 Platform, Standard Edition, v1.4. This component enables
applications to read data stored in the DNS.
<li>
The JNDI Lightweight Directory Access Protocol (LDAP) service provider
has security enhancements that enable applications to
establish secure sessions over existing LDAP connections and
to use different authentication protocols.
<li>
The JNDI CORBA Object Services (COS) naming service provider supports
the <a href="ftp://ftp.omg.org/pub/docs/ptc/99-12-03.pdf">Interoperable
Naming Service (INS) specification (99-12-03)</a>.
</ul>
<blockquote>
See <a href=../guide/jndi/index.html#14changes>JNDI Enhancements</a> for details.
</blockquote>
<p>
<a name="corba"></a>
<li><b>CORBA, <a href="../guide/idl/index.html">Java IDL</a>, and
<a href="../guide/rmi-iiop/index.html">RMI-IIOP</a></b>
<blockquote>
The ORB shipping as part of Java 2 Platform now includes a Portable Object
Adapter (POA) functionality. An ORB makes it possible for client(s) to make
method invocations on the objects being supported by server(s) executing
on the same or different machine(s). ThePOA functionality
allows programmers to construct object implementations that are portable
between different ORB products, provide support for objects with
persistent identities, and much more. Other new features
include Portable Interceptors, Interoperable Naming Service,
GIOP 1.2 support, Dynamic Management of Any values, and
new tools that support a persistent naming service and other
features. To learn more about the new features in Java IDL
and RMI-IIOP between J2SE v.1.3 and J2SE v.1.4, link to
<a href="../guide/idl/jidlChanges.html"><em>Changes in
CORBA Features Between J2SE 1.3 and 1.4</em></a>.
</blockquote>
<p>
<a name="jpda"></a>
<li><b><a href="../guide/jpda/index.html">Java<sup><font size="-2">TM</font></sup> Platform Debugger Architecture</a></b>
<blockquote>
<b>Full Speed Debugging Support</b><br>
The
<a href="http://java.sun.com/products/hotspot/">
Java HotSpot[TM] virtual machine
</a>
now uses "full-speed debugging". In the previous version of HotSpot, when
debugging was enabled, the program executed using only the interpreter. Now,
the full performance advantage of HotSpot
Technology is available to programs running with debugging enabled.
The improved performance allows long running programs to
be more easily debugged. It also allows testing to proceed
at full speed and the launch of a debugger to occur on an exception.
<p>
<b>HotSwap</b><br>
This feature has been added to allow a class to be updated while under the control of a debugger.
<p>
<b>Instance Filters</b><br>
<code>EventRequests</code> now have the capability of specifying an instance filter, which
restricts the events generated by the request to those in which the currently executing
instance is the object specified.
<p>
<b>Support For Debugging Other Languages</b><br>
The Java Platform Debugger Architecture has been extended so that non-Java programming
language source, which is translated to Java programming language source, can be debugged in the
future.
<p>
<b>VMDeathRequests</b><br>
A request can now be made to control target VM termination notification, allowing clean shutdown
synchronization
</blockquote>
<p>
<a name="i18n"></a>
<li><b><a href="../guide/intl/index.html">Internationalization</a></b>
<blockquote>
<b>Unicode 3.0 Support</b><br>
Character handling in J2SE 1.4 is based on version 3.0 of the Unicode
standard. This affects the Character and String classes in the java.lang
package as well as the collation and bidirectional text analysis
functionality in the java.text package.
<p>
<b>Support for Thai and Hindi</b><br>
Thai and Hindi are now supported in all areas of functionality. See the
<a href="../guide/intl/locale.doc.html">Supported Locales</a> document
for complete information on supported locales and writing systems.
<p>
<b>Currency class</b><br>
The class <a href="../api/java/util/Currency.html"><tt>java.util.Currency</tt></a> was introduced so that currencies can be
referenced independent of locales. There are new methods on
<a href="../api/java/text/NumberFormat.html"><tt>java.text.NumberFormat</tt></a> and related classes to specify the currency for
formatting monetary values.
</blockquote>
<p>
<a name="plugin"></a>
<li><a href="../guide/plugin/index.html"><b>Java<sup><font size="-2">TM</font></sup> Plug-in Product</b></a>
<blockquote>
Java Plug-in 1.4 offers the following new features: support of HTTPS
through Java Secure Socket Extension (JSSE) rather than the browser;
enhanced applet caching so that other files, such as GIF, JPEG, AU,
etc., can be cached as part of the download in addition to JAR and
class files; applet persistence so that applets may persist across
browser page changes; various applet-compatibility
enhancements to allow most JDK 1.1 applets to run seemlessly in Java 2;
and on Microsoft Windows platforms, support in Java Plug-in for launching
applets using the <tt><APPLET></tt> tag.
<p>
Version 1.4 also provides access to the DOM via standard, w3c-defined
interfaces; assertion and logging support; applet usability enhancements,
including a customizable progress bar for applet loading; and enhanced
options in the Java Console to allow dynamic reconfiguration of proxy
settings, the policy file, etc., while the applet is running.
</blockquote>
<p>
<a name="collections"></a>
<li><a href="../guide/collections/index.html"><b>Collections Framework</b></a>
<blockquote>
The collections framework has several enhancements in Java 2 SDK 1.4,
including a marker interface to advertise random access, an identity-based
(rather than equality-based) Map, insertion-order-preserving Map and
Set implementations, and several new algorithms for manipulating and
returning values from lists. See <a href="../guide/collections/changes4.html">Collections Framework Enhancements</a> for details.
</blockquote>
<p>
<a name="access"></a>
<li><a href="../guide/access/index.html"><b>Accessibility</b></a>
<blockquote>
New features include support for:
<ul>
<li>Mnemonic tab navigation on a JTabbedPane
<li>Text editing by assistive technologies
<li>Accessibility of HTML components
<li>Accessibility of Swing Actions
<li>List navigation using the first letter of list items
<li>Component roles DATE_EDITOR, FONT_CHOOSER, GROUP_BOX, SPIN_BOX, STATUS_BAR
<li>Properties to indicate the presence of a screen magnifier or screen
reader, or to specify assistive technologies to load into the Java virtual
machine
</ul>
</blockquote>
<p>
<a name="regex"></a>
<li><a href="../api/java/util/regex/package-summary.html"><b>Regular Expressions</b></a>
<blockquote>
New package <a href="../api/java/util/regex/package-summary.html"><tt>java.util.regex</tt></a>
contains classes for matching character sequences against patterns
specified by regular expressions.
</blockquote>
<p>
<a name="math"></a>
<li><a href="../guide/math/index.html"><b>Math</b></a>
<blockquote>
A new, efficient method for generating prime numbers with
no need for the caller to specify a certainty has been added
to class <tt>java.math.BigInteger</tt>.
</blockquote>
<p>
<a name="reflection"></a>
<li><a href="../guide/reflection/index.html"><b>Reflection</b></a>
<blockquote>
Certain reflective operations, specifically
<a href="../api/java/lang/reflect/Field.html">java.lang.reflect.Field</a>,
<a href="../api/java/lang/reflect/Method.html#invoke(java.lang.Object, java.lang.Object[])">java.lang.reflect.Method.invoke()</a>,
<a href="../api/java/lang/reflect/Constructor.html#newInstance(java.lang.Object[])">java.lang.reflect.Constructor.newInstance()</a>, and <a href="../api/java/lang/Class.html#newInstance()">Class.newInstance()</a>,
have been rewritten for higher performance. Reflective
invocations and instantiations are several times faster than in
previous releases.
</blockquote>
<p>
<a name=jni></a>
<li><a href="../guide/jni/index.html"><b>Java Native Interface</b></a>
<blockquote>
A few changes have been made to JNI in v 1.4.
First, the version number has been incremented
and the specification of <tt>JNI_OnLoad</tt> updated accordingly.
Second, JNI has been enhanced to reflect a new feature of the
<tt>java.nio</tt> package: <i>direct buffers</i>. The contents of a
direct buffer can, potentially, reside in native memory outside
of the ordinary garbage-collected heap. Finally, the new Invocation Interface
routine <tt>AttachCurrentTreadAsDaemon</tt> allows native code to attach
a daemon thread to the virtual machine; this is useful when the VM should
not wait for this thread to exit upon shutdown.
See <a href="../guide/jni/jni-14.html"><b>JNI Enhancements</b></a> for
more on these enhancements.
</blockquote>
</ul>
<h2>Tools and Utilities</h2>
<a name=tools></a>
<blockquote>
See <a href=../tooldocs/tools-changes.html><b>Tool Changes</b></a> for
details on the changes summarized here.
</blockquote>
<ul>
<li> The <a href="../tooldocs/solaris/java.html"><b>java</b></a>
application launcher supports
command-line options for support of the new Assertions Facility.
On the Solaris<sup><font size="-2">TM</font></sup> Operating Environment
(SPARC<sup><font size="-2">TM</font></sup> Platform Edition) new
command-line options are available for specifying 64-bit or
32-bit operation. On all platforms, new option <tt>-Xloggc:<i>file</i></tt>
logs each garbage-collection event in the specified file.
Also on all platforms, the new option <tt>-Xcheck:jni</tt> performs additional
checks for Java Native Interface (JNI) functions at the cost of some
performance degradation
<p><li>The <a href="../tooldocs/solaris/javadoc.html"><b>javadoc</b></a>
tool has several new tags, a dozen new options, smarter inheriting
of doc comments, more control over HTML output, improvements to
the Doclet API, better error messages, dozens of bug fixes, and
is easier to run.
For more details, see <a href=../tooldocs/javadoc/whatsnew-1.4.html>What's
New in Javadoc 1.4</a>.
Downloaded separately from the SDK, the
<a href="http://java.sun.com/javadoc/mifdoclet/">MIF doclet</a>
has had a major upgrade -- it generates API documentation
in FrameMaker and PDF format.
<p><li> The <a href="../tooldocs/solaris/native2ascii.html"><b>native2ascii</b></a>
tool contains bug fixes to now correctly
process source files encoded with Unicode encoding.
<p><li>The <a href="../guide/rmi-iiop/toJavaPortableUG.html"><b>idlj</b></a> tool now generates server-side bindings following the <em>Portable Servant Inheritance Model</em>.
This change involves producing new POA bindings by default. A new command-line
option is added to enable you to continue to generate backwards-compatible server-side
bindings. To learn more about the <a href="../guide/idl/POA.html">Portable Servant Inheritance Model</a>, follow the link.
<p><li>The <a href="../guide/idl/orbd.html"><b>orbd</b></a> tool, or <em>Object Request Broker Daemon</em>, is a new alternative tool for the Transient
Naming Service, <tt>tnameserv</tt>. ORBD includes both a Transient Naming Service
and a Persistent Naming Service. The <B>orbd</B> tool is used to enable
clients to transparently locate and invoke persistent objects on servers in the
CORBA environment. The <b>orbd</b> tool incorporates the functionality of a Server Manager,
an Interoperable Naming Service, and a Bootstrap Name Server. When used in conjunction
with the <tt>servertool</tt>, the Server Manager locates, registers, and activates
a server when a client wants to access the server.
<p><li>The <a href="../guide/idl/servertool.html"><b>servertool</b></a> is new to this release. The <b>servertool</b> provides
an ease-of-use interface for application programmers to register, unregister,
startup, and shutdown a server.
<p><li>The <a href="../tooldocs/solaris/rmic.html"><b>rmic</b></a> compiler has a new option to enable Portable Object Adapter, or <em>POA</em> support for Remote Method Invocation. The POA enables portability among vendor ORBs, among other uses. To learn more about the <a href="../guide/idl/POA.html">POA</a>, follow the link. To enable POA support with the <tt>rmic</tt> compiler, use the arguments <tt>rmic -iiop -poa</tt>.
<p><li>The graphical <b>Policy Tool</b> utility has been enhanced
to enable specifying a Principal field indicating what user is to be
granted specified access control permissions.
</ul>
<br>
<!-- Body text ends here -->
<!-- ============================================================== -->
<HR SIZE=3 NOSHADE>
<TABLE summary="layout" BORDER="0" WIDTH=100%>
<TR VALIGN=TOP>
<TD>
<P><FONT SIZE="-2"><A HREF="SMICopyright.html">Copyright © 2002</A>
Sun Microsystems, Inc. All Rights Reserved.</FONT></P>
<br>
<br>
<FONT SIZE="-1">
</FONT>
</TD>
<TD ALIGN=RIGHT>
<IMG SRC="../images/sunlogo64x30.gif" ALT=" Sun Microsystems, Inc " BORDER=0 WIDTH=64 HEIGHT=30>
<BR>
</TD>
</TR>
</TABLE>
<pre>
<!-- THESE pre TAGS ALLOW LINKS TO JUMP TO BOTTOM OF PAGE -->
</pre>
</BODY>
</HTML>
JavaBean ：是一种组件，它在内部有接口或有与其相关的属性，以便不同人在不同时间开发的 bean 可以询问和集成。可以构建一个 bean，而在以后构造时将其与其它 bean 绑定。这种过程提供了先构建，然后重复使用的方法，这就是组件的概念。可以将这种单一应用程序部署成独立程序、ActiveX 组件或在浏览器中。JavaBean 因其外部接口（即属性接口）而与纯对象不同。这种接口允许工具读取组件要执行的功能，将其与其它 bean 挂钩，以及将其插入其它环境。JavaBean 设计成对单一进程而言是本地的，它们在运行时通常可视。这种可视组件可能是按钮、列表框、图形或图表 - 但这不是必需的。
EJB：
EJB的全称是Enterprise Java bean。是JAVA中的商业应用组件技术。EJB结构中的角色 EJB 组件结构是基于组件的分布式计算结构，是分布式应用系统中的组件。
一个完整的基于EJB的分布式计算结构由六个角色组成，这六个角色可以由不同的开发商提供，每个角色所作的工作必须遵循Sun公司提供的EJB规范，以保证彼此之间的兼容性。这六个角色分别是EJB组件开发者（Enterprise Bean Provider）、应用组合者（Application Assembler）、部署者（Deployer）、EJB服务器提供者（EJB Server Provider）、EJB 容器提供者（EJB Container Provider）、系统管理员（System Administrator）
EJB 是设计成运行在服务器上，并由客户机调用的非可视远程对象。可通过多个非可视 JavaBean 构建 EJB。它们有一个部署描述符，其目的与 JavaBean 属性相同：它是以后可由工具读取的 bean 的描述。EJB 还独立于平台，一旦编写好，还可以在任何支持 Java 的平台（包括客户机和服务器）上使用。
因为 EJB 由诸如 IBM VisualAge for Java 这样的工具集生成，所以，它是基于服务器的对象，并用于远程调用。它们安装在 EJB 服务器上，并象调用其它 CORBA 远程对象那样获得进行调用的远程接口。
EJB 的主要好处在于：构建 bean 时，bean 开发人员可以规定需要什么类型的行为，而不必规定如何去做。开发分为两部分：程序员开发 bean，然后验证：它可与构建工具一起工作，并包括标识所需服务质量行为种类的部署描述符。下一步，另一个程序员可以采用这个 bean，并使用读取 EJB 部署描述符的部署工具，然后将该 bean 安装到 Enterprise Java Server 上的容器中。在第二步中，部署工具采取一些操作 - 这可能意味着生成如状态保存代码，放入事务挂钩，或执行安全性检查这样的代码。所有这些操作由部署工具生成，bean 开发人员和部署人员可以是不同的人。
可以通过使用部署工具，将任何独立于平台的 JavaBean 改写成具有可靠服务质量、特定于平台的 EJB，以满足现有商业系统和应用程序的特定需求。这就是 EJB 服务器对集成系统、网络和体系结构如此重要的原因所在。
JBuilder
Jbuilder是一个荣获多项奖项的产品，Inprise一向有支持开发者社区的传统，因此Jbuilder同时推出了linux的版本。Jbuilder提供一个可视化的开发集成环境，你可以方便的开发纯JAVA应用程序，APPLET,JAVA BEANS以及兼容J2EE的分布式的企业应用。Jbuilder可以和Enhydra，Bea WebLogic协同工作，加速团队的开发速度。总之，作JAVA应用开发，用JBUILDER，能够倍感轻松。
JCreator
JCreator 是一个Java程序开发工具，无论你是要开发Java应用程序或者网页上的Applet元件都难不倒它。在功能上与Sun公司所公布的JDK等文字模式程序工具相较之下来得容易操作，还允许使用者自订义操作窗口界面及无限Undo /Redo等功能。
JNDI
JNDI的全称是Java Naming and Directory Interface， 可以理解为Java名称和目录服务接口。
JNDI向应用程序提供了一个查询和使用远程服务的机制。这些服务可以是任何企业服务。对于JDBC应用程序来说，JNDI提供的是数据库连接服务。当然JNDI也可以向数据库提供其他服务，但是这超出了本文范围，在此不做论述。
其实JNDI并不难理解。简单来说，名称服务提供了一个把文件，打印机，服务器等实体映射到一个逻辑名称的机制。例如在操作系统中的名称服务就把打印机映射到一个I/O端口。而目录服务可以理解为名称服务的一个扩展，它允许在服务中的各项拥有自己的属性。又以打印机为例，打印机可以是彩色打印机，支持双面打印，支持网络打印，支持高速打印等。所有这些打印机的属性都可以储存在目录服务中，和相应的打印机联系起来。一些常见的目录服务有NIS，NIS+，LDAP和Novell的NDS等。
那么现在已经很入门了，回到第一篇再看看，是不是有收获~！
