其 他 一 些 關 於
JAVA 的 資 訊
其 他 的 作 業 系 統 對 JAVA 的 支 援
那 些 地 方 可 以 找 到 更 多 的 Java Applets
- The Java home page at http://www.java.sun.com/
is the official source for Java information, including information about
the JDK, about the upcoming 1.1, and about developer tools such as the
Java Workshop, as well as extensive documention.
- Gamelan, at http://www.gamelan.com/,
is a repository of applets and Java information, organized into categories.
If you want to play with applets or applications, this is the place to
look.
- For Java discussion, check out the comp.lang.java
newsgroups, including comp.lang.java.programmer,
comp.lang.java.tech, comp.lang.java.advocacy,
and so on.
Java 1.1 有 那 些 新 的 功
能
- JDBC (the Java Database Connectivity interface) provides
a mechanism for connecting Java applications and apples to SQL databases
such as Oracle and Sybase, The JDBC, available in a prerelease from at
this time from http://splash.javasoft.com/jdbc/.
- RMI (Remote Method Invocation) is the ability to call
a Java method from an object running elsewhere (for example, in a different
Java environment running on the same machine or on any machine on the network).
RMI is closely related to object serialization, which allows objects to
be encoded into a stream of bytes, which can then be sent over a network
or saved to a file. The result can then also be decoded back into a Java
object at the other end. Information about both of these topic can be found
at http://chatsubo.javasoft.com/current/.
- The Java native methods interface is the ability for
Java to call system-specific libraries such as DLLs or loadable libraries
written in C; enhancement in Java 1.1 will include a better API for making
sure native method libraries are compatible with every implementation of
the Java runtime across platforms.
- JIT compilers are tools that convert Java bytecode to
native machine code. In Java 1.1 there will be better specifications for
writing your own JIT or other tool that generates native code from Java
bytecodes.
- Changes to the AWT. Probably some of the more significant
changes to Java will be in the area of the Abstract Windowing Toolkit,
or AWT, the portion of Java that controls drawing to the screen, creating
user interface elements such as buttons and windows, and handling painting
and use input between and those elements. Enhancements to AWT in Java 1.1
include pringing, pop-up menus, supports for clipboards (copy and paste),
internationalization for fonts, better scrolling capabilities, and delegation-based
events.
- Security enhancement. JDK 1.1 will provide many features
for implementing security in Java applications, include signatures, access
control, key management, and message digests (MD5 hashes, for example).
These additions won't affect much of 1.0 because the are new enhancements.
- Networking enhancements. Java 1.0 provides the java.net
classes, which provide simple network connections, URL management, and
simple client and server sockets. Java 1.1 provides more flexibility for
the existing socket classes, a new MulticastSocket class, and BSD-style
socket options. Learn about all these new features from the URL http://java.sun.com/products/JDK/1.1/designspecs/net/index.html.
- Adapter classes allow you to implement an API defined
by an interface or a class and have the flow of control move from the adapter
class back to an enclosing object. Java 1.1 provides Java syntax for nesting
class definitions inside other class definitions to more easily create
adapter classes.
- Object reflection is the ability for Java to inspect
an object and find out its methods and variables (and call and change them).
Object reflection is useful for class browsers or other tools that need
to find out information about an object on-the-fly, as well as component
object systems that need defined ways of referring to other objects' contents.
Java 1.1 provides many features for handling object reflection, including
a number of new classes. You'll find out more from http://java.sun.com/products/JDK/1.1/designspecs/reflection/index.html.
- Java 1.1 provides a number of new features for internationalization,
particularly language-specific features such as strings, character set
conversions, Unicode character display, and support for definable "locales."
- Java archives (JAR files) provide a mechanism for combining
serveral classes into a single file for faster downloading over the Net.
Netscape provides a single archive file mechanism for applets, but JAR
files provide a more cross-platform file format, compression, and the ability
to include media files in the archive. The capability to store Java classes
in JAR files, and to use them with Java-enabled browsers, will be in Java
1.1. The current JAR file format specification is available from http://java.sun.com/security/codesign/jar-format.html.